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Publications

The latest Tunable Resistive Pulse Sensing (TRPS) and qEV Isolation publications.

Featured TRPS publications

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A new transgene mouse model using an extravesicular EGFP tag to elucidate the in vivo function of extracellular vesicles
The in vivo function of cell-derived extracellular vesicles (EVs) is challenging to establish since cell-specific EVs are difficult to isolate. We therefore created an EV reporter using CD9 to display enhanced green fluorescent protein (EGFP) on the EV surface. CD9-EGFP expression in cells did not affect EV size and concentration, but allowed for co-precipitation of EV markers TSG101 and ALIX from cell-conditioned medium by anti-GFP immunoprecipitation. We created a transgenic mouse where CD9-EGFP was inserted in the inverse orientation and double-floxed, ensuring Cre recombinase-dependent EV reporter expression. We crossed the EV reporter mice with mice expressing Cre ubiquitously (CMV- Cre), in cardiomyocytes (AMHC-Cre) and kidney epithelium (Pax8-Cre), respectively. The mice showed tissue-specific EGFP expression, and plasma and urine samples were used to immunoprecipitate EVs. CD9-EGFP EVs was detected in plasma samples from CMV-Cre/CD9-EGFP and AMHC-Cre/CD9-EGFP mice, but not in PAX8-Cre/CD9-EGFP mice. On the other hand, CD9-EGFP EVs were detected in urine samples from CMV-Cre/CD9-EGFP and PAX8-Cre/CD9-EGFP mice, but not AMHC-Cre/CD9-EGFP, indicating that plasma EVs are not filtered to the urine. In conclusion, our EV reporter mouse model enables Cre-dependent EV labeling, providing a new approach to study cell-specific EVs in vivo and gain new insight into their physiological and pathophysiological function.
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2021
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A perspective on the isolation and characterization of extracellular vesicles from different biofluids
Extracellular vesicles (EVs) are small membrane-bound particles, which include exosomes, micro vesicles (MVs) and various-sized vesicles, released by healthy and diseased cells. EVs also include other vesicular structures, such as large apoptotic bodies (1–5 μm), as well as membrane particles (50–80 nm) originating from the plasma membrane. However, exosomes are nanosize (≈30–100 nm) extracellular vesicles of endocytic origin that are bud-off by most types of cells and circulate in bodily fluids. Extracellular nanovesicles contain a large variety of biomolecules, including miRNA, RNA, DNA, proteins, signaling peptides and lipids, that can have diagnostic and therapeutic value. The spectrum of the existing scientific interest in extracellular nanovesicles is comprehensive, which ranges from understanding their functions and pathways to their potential clinical usage. EVs can be obtained from different body fluids with minimally invasive techniques (e.g., urine, plasma, serum), so they are most useful in disease diagnosis. High yield and purity contribute to the accurate diagnosis of various diseases, but damaged EVs and impurities can cause misinterpreted results. Over the last decade, a plethora of approaches have been developed for examining EVs using optical and non-optical tools. However, EV isolation methods have different yields and purities. Moreover, the isolation method that is most appropriate to maximize EVs recovery depends on the different experimental situations. This review explores the emerging use of micro and nano-technologies to isolate and characterize exosomes and microvesicles (MVs) from different biological samples, and the application of these technologies for the monitoring and diagnosis of different pathological conditions.
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2021
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A simple displacement aptamer assay on resistive pulse sensor for small molecule detection
A universal aptamer-based sensing strategy is proposed using DNA modified nanocarriers and Resistive Pulse Sensing (RPS) for the rapid (≤20 min) and label free detection of small molecules. The surface of a magnetic nanocarrier was first modified with a ssDNA (anchor) which is designed to be partially complimentary in sequence to the ssDNA aptamer. The aptamer and anchor form a stable dsDNA complex on the nanocarriers surface. Upon the addition of the target molecule, a conformational change takes place where the aptamer preferentially binds to the target over the anchor; causing the aptamer to be released into solution. The RPS measures the change in velocity of the nanocarrier as its surface changes from dsDNA to ssDNA, and its velocity is used as a proxy for the concentration of the target. The length of the aptamer and the ability to extract and preconcentrate the nanocarriers using a magnet, is shown to affect the sensitivity. We illustrate the versatility of the assay using the same anchor sequence and Aptamers to the antibiotic Moxifloxacin, and chemotherapeutics Imatinib and Irinotecan. In addition, the proposed assay can be easily extended to detect multiple analytes simultaneously, by utilizing nanocarriers with different diameters. Each sized particle is functionalised with a the same anchor but a unique aptamer. We illustrate this with the simultaneous detection of Imatinib and Moxifloxacin. The strategy could be easily adapted to a range of targets and unlike previous strategies that use aptamer modified nanocarriers, the signal is not dependent upon the tertiary structure of the aptamer-target interaction.
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2021
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Aberrant Membrane Structures in Hypervesiculating Escherichia coli Strain ΔmlaEΔnlpI Visualized by Electron Microscopy
Escherichia coli produces extracellular vesicles called outer membrane vesicles (OMVs) by releasing a part of its outer membrane. We previously reported that the combined deletion of nlpI and mlaE, related to envelope structure and phospholipid accumulation in the outer leaflet of the outer membrane, respectively, resulted in the synergistic increase of OMV production. In this study, the analysis of ΔmlaEΔnlpI cells using quick-freeze, deep-etch electron microscopy (QFDE-EM) revealed that plasmolysis occurred at the tip of the long axis in cells and that OMVs formed from this tip. Plasmolysis was also observed in the single-gene knockout mutants ΔnlpI and ΔmlaE. This study has demonstrated that plasmolysis was induced in the hypervesiculating mutant E. coli cells. Furthermore, intracellular vesicles and multilamellar OMV were observed in the ΔmlaEΔnlpI cells. Meanwhile, the secretion of recombinant green fluorescent protein (GFP) expressed in the cytosol of the ΔmlaEΔnlpI cells was more than 100 times higher than that of WT and ΔnlpI, and about 50 times higher than that of ΔmlaE in the OMV fraction, suggesting that cytosolic components were incorporated into outer-inner membrane vesicles (OIMVs) and released into the extracellular space. Additionally, QFDE-EM analysis revealed that ΔmlaEΔnlpI sacculi contained many holes noticeably larger than the mean radius of the peptidoglycan (PG) pores in wild-type (WT) E. coli. These results suggest that in ΔmlaEΔnlpI cells, cytoplasmic membrane materials protrude into the periplasmic space through the peptidoglycan holes and are released as OIMVs.
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2021
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An integrated workflow for biomarker development using microRNAs in extracellular vesicles for cancer precision medicine
EV-miRNAs are microRNA (miRNA) molecules encapsulated in extracellular vesicles (EVs), which play crucial roles in tumor pathogenesis, progression, and metastasis. Recent studies about EV-miRNAs have gained novel insights into cancer biology and have demonstrated a great potential to develop novel liquid biopsy assays for various applications. Notably, compared to conventional liquid biomarkers, EV-miRNAs are more advantageous in representing host-cell molecular architecture and exhibiting higher stability and specificity. Despite various available techniques for EV-miRNA separation, concentration, profiling, and data analysis, a standardized approach for EV-miRNA biomarker development is yet lacking. In this review, we performed a substantial literature review and distilled an integrated workflow encompassing important steps for EV-miRNA biomarker development, including sample collection and EV isolation, EV-miRNA extraction and quantification, high-throughput data preprocessing, biomarker prioritization and model construction, functional analysis, as well as validation. With the rapid growth of “big data”, we highlight the importance of efficient mining of high-throughput data for the discovery of EV-miRNA biomarkers and integrating multiple independent datasets for in silico and experimental validations to increase the robustness and reproducibility. Furthermore, as an efficient strategy in systems biology, network inference provides insights into the regulatory mechanisms and can be used to select functionally important EV-miRNAs to refine the biomarker candidates. Despite the encouraging development in the field, a number of challenges still hinder the clinical translation. We finally summarize several common challenges in various biomarker studies and discuss potential opportunities emerging in the related fields.
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2021
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Analysis of extracellular vesicles as a potential index for monitoring differentiation of neural lineage cells from induced pluripotent stem cells
To improve cell production efficacy, it is important to evaluate cell conditions during culture. Extracellular vesicles (EVs) secreted from various cells are involved in stem cell differentiation. As EVs carry information about their source cells, we hypothesized that they may serve as a noninvasive index of cell conditions. We evaluated changes in EV morphology, concentration, and microRNA (miRNA) and protein expression in culture supernatants during the differentiation of induced pluripotent stem cells (iPSCs) into neural lineage cells, for application in regenerative medicine for Parkinson's disease. We observed EVs (50–150 nm) in culture supernatants of iPSCs and differentiated cells. The EVs expressed the exosome markers CD63, CD81, and CD9. Throughout differentiation, the EV concentration in the supernatants decreased, and EV miRNA and protein expression changed substantially. Especially, miR-106b, involved in neural stem cell differentiation and normal brain development, was considerably downregulated. CD63 expression correlated with the CORIN-positive cell rate, which is an index of differentiation. Thus, EV concentration and miRNA and protein expression may reflect the differentiation status of iPSCs. These findings pave the way for the development of novel and sensitive cell culture monitoring methods.
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2021
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Analyzing Inter-Leukocyte Communication and Migration In Vitro: Neutrophils Play an Essential Role in Monocyte Activation During Swarming
Neutrophils are known to be the first responders to infection or injury. However, as inflammation progresses, other leukocytes become increasingly important in inflammation propagation, tissue reconstruction, and inflammation resolution. In recent years, there has been an increase in publications that analyze neutrophil behavior in vitro, but there remains a gap in the literature for in vitro technologies that enable quantitatively measuring interactions between different types of human leukocytes. Here, we used an in vitro platform that mimics inflammation by inducing neutrophil swarming to analyze the behavior of various leukocytes in a swarming setting. Using human peripheral blood leukocytes isolated directly from whole blood, we found that myeloid cells and lymphoid cells had different migratory behaviors. Myeloid cells, which are predominately neutrophils, exhibited swarming behavior. This behavior was not seen with lymphoid cells. We perturbed the peripheral blood leukocyte system by adding exogenous leukotriene B4 (LTB4) to the medium. Notably, only the myeloid cell compartment was significantly changed by the addition of LTB4. Additionally, LTB4 had no significant impact on myeloid cell migration during the recruitment phase of swarming. To further investigate the myeloid cell compartment, we isolated neutrophils and monocytes to analyze their interaction on the platform. We found that neutrophils increase monocyte migration toward the bioparticle clusters, as measured through speed, chemotactic index, track straightness, and swarm size. These results were confirmed with in vivo mouse experiments, where monocyte accumulation only occurred when neutrophils were present. Additionally, we found that both neutrophils and monocytes release the monocyte chemoattractant proteins CCL2 and CCL3 in the presence of Staphylococcus aureus bioparticles. Furthermore, extracellular vesicles from swarming neutrophils caused monocyte activation. These findings suggest that neutrophils play an essential role in the onset of inflammation not only by sealing off the site of infection or injury, but also by recruiting additional leukocytes to the site.
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2021
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Applications of cell resealing to reconstitute microRNA loading to extracellular vesicles
MicroRNAs (miRNAs) are cargo carried by extracellular vesicles (EVs) and are associated with cell–cell interactions. The response to the cellular environment, such as disease states, genetic/metabolic changes, or differences in cell type, highly regulates cargo sorting to EVs. However, morphological features during EV formation and secretion involving miRNA loading are unknown. This study developed a new method of EV loading using cell resealing and reconstituted the elementary miRNA-loading processes. Morphology, secretory response, and cellular uptake ability of EVs obtained from intact and resealed HeLa cells were comparable. Exogenously added soluble factors were introduced into multivesicular endosomes (MVEs) and their subsequent secretion to the extracellular region occurred in resealed HeLa cells. In addition, miRNA transport to MVEs and miRNA encapsulation to EVs followed a distinct pathway regulated by RNA-binding proteins, such as Argonaute and Y-box binding protein 1, depending on miRNA types. Our cell-resealing system can analyze disease-specific EVs derived from disease model cells, where pathological cytosol is introduced into cells. Thus, EV formation in resealed cells can be used not only to create a reconstitution system to give mechanistic insight into EV encapsulation but also for applications such as loading various molecules into EVs and identifying disease-specific EV markers.
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2021
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Biophysical and Computational Studies of Human Disease Related Proteins with a Single-Pass Transmembrane Helix
Single-pass transmembrane receptors (SPTMRs) are involved in essential processes of biophysical and pathological nature in the human. This membrane protein family includes receptor tyrosine kinases, integrins, and immunoreceptors, which play an important role in metabolism, growth, proliferation, and apoptosis. SPTMR consists of several distinct domains including the extracellular domain (ECD), the transmembrane domain (TMD), and the intracellular domain (ICD) and exists as a monomer, homo- and/or heterodimer. Upon a ligand ligation through ECD, homo- or heterodimerization of SPTMR forms, followed by consequent modification of the ICDs, leading to the initiation of cellular signaling events. This activation requires interactions between TMD helices whose role in receptor activation becomes important. TMD is further highlighted by the discovery of mutations in the TMD or juxtamembrane domain (JMD) that are associated with human diseases. However, the details of cross-membrane signal transduction via SPTMRs have to be elucidated. Due to the high conformational flexibility of SPTMRs with their diverse structural composition, it is hard to characterize SPTMRs structurally. This drives us to work with only TMD helices of SPTMRs and focus on their interactions in the lipid bilayer environment. Our approach is the use of not only experimental data but also computational MD simulations to understand how TMD helices interact and how mutants associated with diseases affect the dimerization of TMD helices.
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2021
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Bone marrow mesenchymal stem cell derived exosomes delay the occurrence and development of osteoarthritis through cartilage protection
Osteoarthritis is the most common joint degenerative disease. At present, bone marrow mesenchymal stem cells have been used in the treatment of osteoarthritis. However, compared with bone marrow mesenchymal stem cells, bone marrow mesenchymal stem cell derived exosome transplantation has more advantages, such as non-immunogenicity, non-tumorigenicity, convenient storage and transportation. OBJECTIVE: To explore the protective effect of bone marrow mesenchymal stem cell exosomes on osteoarthritis.  METHODS: (1) SD rat bone marrow mesenchymal stem cells were extracted and identified by cell morphology and flow cytometry. Exosomes in the cell supernatant were extracted by ultracentrifugation and identified by transmission electron microscopy, particle size and western blot assay. (2) Primary costal chondrocytes were extracted from suckling rats and cocultured with fluorescently labeled exosomes for 12 hours. The phagocytosis of chondrocytes was observed. In vitro chondrocyte damage was induced by interleukin-1β. PBS (100 μL) containing 50 μg exosomes was added for 24 hours. The expression of matrix metalloproteinase-13 and type II collagen fiber α1 protein was detected by immunofluorescence to evaluate the protective effect of exosomes on injured chondrocytes. (3) The rat model of osteoarthritis was induced by iodoacetic acid in vivo. Exosomes were injected into the joint cavity, and the changes of joint structure of osteoarthritis were observed by hematoxylin-eosin staining and safrane-fast green staining. The expression of matrix metalloproteinase-13 and type II collagen fiber α1 protein was measured by immunohistochemical staining to evaluate the protective effect of exosomes on cartilage in vivo.  RESULTS AND CONCLUSION: (1) The extracted primary cells showed a typical fusiform shape and arranged radially. The extracted cells highly expressed CD73 and CD105, but slightly expressed CD45, CD34 and CD3. Transmission electron microscopy showed that the obtained particles showed a typical saucer-like morphology. The particle size was less than 100 nm. Meanwhile, nanoparticles showed positive expression of ALIX and HRS protein. (2) Typical red-stained particles could be observed in chondrocytes, which confirms that exosomes could be taken up by chondrocytes, and exosomes could promote chondrocyte type II collagen fiber α1 protein expression, but inhibit the expression of matrix metalloproteinase-13, which confirmed that exosomes could attenuate the damage effect of interleukin-1β on chondrocytes. (3) Exosomes could promote the morphological recovery of damaged articular cartilage and the up-regulate type II collagen fiber α1 expression, while inhibited the expression of matrix metalloproteinase-13, which also confirmed that exosomes can alleviate the effects of iodoacetic acid on articular cartilage damage. (4) Above findings results indicate that bone marrow mesenchymal stem cell exosomes delay the occurrence and development of osteoarthritis through a chondroprotective mechanism.
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2021
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Bone Marrow Mesenchymal Stem Cells-Derived Extracellular Vesicles Promote Proliferation, Invasion and Migration of Osteosarcoma Cells via the lncRNA MALAT1/miR-143/NRSN2/Wnt/β-Catenin Axis
Introduction Osteosarcoma is a malignant primary bone tumor. Bone marrow-derived mesenchymal stem cells-derived extracellular vesicles (BMSC-EVs) bear repair function for bone and cartilage. This study investigated the mechanism of BMSC-EVs in osteosarcoma cell proliferation, migration and invasion. Methods BMSC-EVs were isolated and identified. The effects of different concentrations of EVs on osteosarcoma cell proliferation, migration and invasion were evaluated. LncRNA MALAT1 expression in osteosarcoma cells was detected. BMSCs were transfected with si-MALAT1 or si-NC. The binding relationships between MALAT1 and miR-143, and miR-143 and NRSN2 were verified. Levels of NRSN2 and Wnt/β-catenin pathway key proteins were detected. miR-143 mimic was transfected into EVs-treated osteosarcoma cells. Nude mice were injected with MG63 cells to verify the effect of EVs on osteosarcoma growth in vivo. Results BMSC-EVs facilitated proliferation, invasion and migration of osteosarcoma cells. BMSC-EVs carried MALAT1 into osteosarcoma cells. BMSC-EVs-treated osteosarcoma cells showed increased MALAT1 and NRSN2 expressions, decreased miR-143 expression, and activated Wnt/β-catenin pathway. miR-143 mimic or si-MALAT1 reversed the effects of BMSC-EVs on osteosarcoma cells. In vivo experiment confirmed that BMSC-EVs promoted tumor growth in nude mice. Discussion BMSC-EVs promoted proliferation, invasion and migration of osteosarcoma cells via the MALAT1/miR-143/NRSN2/Wnt/β-catenin axis. This study might offer new insights into osteosarcoma management. Keywords: osteosarcoma, bone marrow-derived mesenchymal stem cells, extracellular vesicles, lncRNA MALAT1, miR-143, NRSN2, Wnt/β-catenin pathway
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2021
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Caracterización de partículas coloidales en el agua del suelo mediante detección sintonizable de pulsos resistivos
The transport of colloids in soil determines the fate of pollutants, nutrients and microorganisms in the environment and the contamination of groundwater. Colloidal retention mechanisms in soils depend on complex interactions between the soil pore walls and colloids. The hypothesis of this thesis is that the interaction of the particulate colloidal pollutants with the colloids present in the soil pore water has a dramatic influence on the transport of pollutants. This is due to the fact that the filtration of colloids in the porous medium depends on the size, shape and charge of the coatings and colloidal aggregates formed between the polluting particles and the suspended soil colloids. Improving the characterization of colloidal particulate pollutants in soil water can help to explain more precisely the role of soil as a filter for pollutants. Emerging technologies in particle characterization can represent an important advance in this characterization. Specifically, the tunable resistive pulse sensing (TRPS) detection technology allows the real (non-hydrodynamic) size of individual particles to be determined with high precision in a polydisperse suspension between 40 nm and 3 micrometers, in addition to determining, also individually, their surface electrical potential. The new knowledge that this technique can provide could lead to a better understanding of the transport of particulate pollutants in the soil, which could improve the diagnosis of potential vulnerability of subsurface waters against pathogenic organisms, engineered nanoparticles and metals bound to colloids, as well as optimize the design of micro and nanopesticide formulations.
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2021
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Cardioprotection by remote ischemic conditioning is transferable by plasma and mediated by extracellular vesicles
Background Remote ischemic conditioning (RIC) by brief periods of limb ischemia and reperfusion protects against ischemia–reperfusion injury. We studied the cardioprotective role of extracellular vesicles (EV)s released into the circulation after RIC and EV accumulation in injured myocardium. Methods We used plasma from healthy human volunteers before and after RIC (pre-PLA and post-PLA) to evaluate the transferability of RIC. Pre- and post-RIC plasma samples were separated into an EV enriched fraction (pre-EV + and post-EV +) and an EV poor fraction (pre-EV- and post-EV-) by size exclusion chromatography. Small non-coding RNAs from pre-EV + and post-EV + were purified and profiled by NanoString Technology. Infarct size was compared in Sprague–Dawley rat hearts perfused with isolated plasma and fractions in a Langendorff model. In addition, fluorescently labeled EVs were used to assess homing in an in vivo rat model. (ClinicalTrials.gov, number: NCT03380663) Results Post-PLA reduced infarct size by 15% points compared with Pre-PLA (55 ± 4% (n = 7) vs 70 ± 6% (n = 8), p = 0.03). Post-EV + reduced infarct size by 16% points compared with pre-EV + (53 ± 15% (n = 13) vs 68 ± 12% (n = 14), p = 0.03). Post-EV- did not affect infarct size compared to pre-EV- (64 ± 3% (n = 15) and 68 ± 10% (n = 16), p > 0.99). Three miRNAs (miR-16-5p, miR-144-3p and miR-451a) that target the mTOR pathway were significantly up-regulated in the post-EV + group. Labelled EVs accumulated more intensely in the infarct area than in sham hearts. Conclusion Cardioprotection by RIC can be mediated by circulating EVs that accumulate in injured myocardium. The underlying mechanism involves modulation of EV miRNA that may promote cell survival during reperfusion.
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2021
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Characterisation of extracellular vesicles in the context of myocardial infarction and glucose intolerance
Introduction In response to myocardial infarction (MI), extracellular vesicles (EVs), including large (lEVs) and small (sEVs), are released within and from the heart to facilitate intercellular communication and maintain cardiac homeostasis by transporting cargo to recipient cells. Objective We investigated how glucose intolerance influences the intracardiac EV release post-MI and their content. Method B6J mice were fed chow (CD) or high-fat diet (HFD) for 3 months. MI was induced by permanent coronary artery ligation. EVs were isolated from left ventricles and quantified by tunable resistive pulse sensing. EVs were characterised by flow cytometry. EV miRNA content was determined by RNAseq and qPCR. Using cardiomyocyte specific GFP+ mice, plasma lEVs were analysed by flow cytometry to determine if cardiomyocyte EVs (CMEVs) are circulating. Labelled hypoxic cardiomyocyte cell line (HL-1) lEVs were injected in HFD/CD mice post-MI to determine target cells. Results In CD mice, EV release was significantly increased 24 h post-MI compared to sham. HFD lEV levels were significantly higher compared to sham and CD mice post-MI with no difference in sEV release between sham and MI HFD mice. Intracardiac lEVs originate from cardiomyocyte and endothelial cells in response to MI and MI + HFD respectively. qPCR analyses identified miRNA candidates that were modulated by MI and HFD. Intracardiac GFP + lEV levels were lower in HFD than in CD mice whereas levels of circulating GFP + lEVs were higher. In vivo biodistribution studies revealed a preferential uptake of hypoxic HL-1 lEVs by splenic myeloid cells in HFD spleens versus CD post-MI. Conclusion Our results show that glucose intolerance modulates intracardiac EV release post-MI and their miRNA cargo. Circulating CMEV levels as well as their uptake by splenic myeloid cells are increased. Further investigations will aim to decipher the impact of the intracardiac EV miRNA mediated transfer in the diabetic heart post-MI.
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2021
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Characterization of feces-derived bacterial membrane vesicles and the impact of their origin on the inflammatory response
The human gastrointestinal tract harbors a diverse and complex microbiome, which interacts in a variety of ways with the host. There is compelling evidence that gut microbial dysbiosis, defined as an alteration of diversity and abundance in intestinal microbes, is an etiological factor in inflammatory bowel disease (IBD). Membrane vesicles (MVs), which are nano-sized particles released by bacteria, have been found to interact with the host and modulate the development and function of the immune system. As a result MVs have been suggested to play a critical role in both health and disease. In this study we developed a method to isolate, characterize and assess the immunoreactivity of heterogeneous populations of MVs from fecal samples (fMVs) of healthy volunteers. We successfully isolated 2*109-2*1010 particles/ml from 0.5 gram of feces by using a combination of ultrafiltration and size exclusion chromatography (SEC) from 10 fecal samples. Bead-based flowcytometry in combination with tunable resistive pulse sensing (TRPS) provided a reliable method for (semi-)quantitative determination of fMVs originating from both Gram-positive and Gram-negative bacteria, while transmission electron microscopy confirmed the presence of fMVs. Real time 16s PCR on bacterial cell fractions or isolated fMVs DNA of the most common phyla (Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria) revealed differences in the relative abundance between bacteria and the fMVs. Moreover, fMVs evoke the release of TNF- by THP-1 cells in a dose-dependent matter. Also, a significant positive correlation was found between Actinobacteria/-Proteobacteria derived vesicles and the release of TNF-. It has become increasingly clear that fMVs could provide an additional layer to the definition of homeostasis or dysbiosis of the microbiota. The current study supports their potential involvement in the intestinal homeostasis or inflammatory disorders and provides putative interesting incentives for future research.
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2021
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Characterization of positively charged polyplexes by tunable resistive pulse sensing
With the approval of the first siRNA-based drugs, non-viral siRNA delivery has gained special interest in industry and academia in the last two years. For non-viral delivery, positively charged lipid and polymer formulations play a central role in research and development. However, nanoparticle size characterization, particularly of polydisperse formulations, can be very challenging. Tunable resistive pulse sensing for particle by particle measurements of size, polydispersity, zeta potential and a direct concentration promises better assessment of nanoparticle formulations. However, the current application is not optimized for positively charged particles. A supplier-provided coating solution for difficult-to-measure samples does not allow for successful measurements of positively charged nanoparticles. This article describes a new coating solution based on choline-chloride. Coating is verified by current–voltage (I-V) recordings and ultimately tested on a positively charged nanoparticle formulation comprising of siRNA and PEG-PCL-PEI polymer. This coating allows successful size, polydispersity index (PDI) and concentration measurement by tunable resistive pulse sensing of positively charged PEI-based polyplexes. This article provides the foundation for further characterization of polyplexes as well as other positively charged nanoparticle formulations based on particle by particle measurements.
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2021
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Characterization of systemic immunosuppression by IDH mutant glioma small extracellular vesicles
Background Gliomas are the most common primary brain tumors and are universally fatal. Mutations in the isocitrate dehydrogenase genes (IDH1 and IDH2) define a distinct glioma subtype associated with an immunosuppressive tumor microenvironment. Mechanisms underlying systemic immunosuppression in IDH mutant (mutIDH) gliomas are largely unknown. Here, we define genotype-specific local and systemic tumor immunomodulatory functions of tumor-derived glioma small extracellular vesicles (TEX). Methods TEX produced by human and murine wildtype and mutant IDH glioma cells (wtIDH and mutIDH, respectively) were isolated by size exclusion chromatography (SEC). TEX morphology, size, quantity, molecular profiles and biodistribution were characterized. TEX were injected into naive and tumor-bearing mice, and the local and systemic immune microenvironment composition was characterized. Results Using in vitro and in vivo glioma models, we show that mutIDH TEX are more numerous, possess distinct morphological features and are more immunosuppressive than wtIDH TEX. mutIDH TEX cargo mimics their parental cells, and induces systemic immune suppression in naive and tumor-bearing mice. TEX derived from mutIDH gliomas and injected into wtIDH tumor-bearing mice reduce tumor-infiltrating effector lymphocytes, dendritic cells and macrophages, and increase circulating monocytes. Astonishingly, mutIDH TEX injected into brain tumor-bearing syngeneic mice accelerate tumor growth and increase mortality compared with wtIDH TEX. Conclusions Targeting of mutIDH TEX represents a novel therapeutic approach in gliomas.
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2021
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Characterizing KRAS Membrane Structures by Data-Driven Molecular Docking
Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA, 2 NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA, 3 Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA, 4 Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA, 5 Data Science, Argonne National Laboratory, Lemont, IL, USA, 6 Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM, USA. KRAS is a GTPase that plays an important role in cell growth and signaling pathways. of the different RAS isoforms, KRAS also has the highest prevalence of mutations related to human cancers, making it an attractive therapeutic target in these cases. Once attached to the membrane, KRAS in the active (GTP) form is capable to bind effector proteins, like RAF kinase. However, certain molecular details concerning KRAS conformation and orientational changes when interacting with the membrane and binding partners are not fully understood. To provide new insights, we used a variety of biophysical approaches to characterize KRAS structure and dynamics. Here, we focus on our results utilizing data-driven computational docking to investigate both KRAS and KRAS/ RAF1-RBD (RAS Binding Domain) complex at the membrane. with the HADDOCK program, we incorporated experimental restraints derived from our NMR paramagnetic relaxation enhancement (PRE) and neutron reflectivity (NR) measurements to dock these KRAS forms to a 70:30 POPC:POPS lipid membrane surface. Using NMR-PRE restraints alone, we performed one series of docking runs with the KRAS G-domain directly interacting with the membrane to discern membrane-proximal states. Based on our experimental evidence, and particularly from NR, a highly populated membrane-distal state also exists, where the G-domain does not directly contact the membrane but KRAS remains tethered via the C-terminal hypervariable region (HVR). Therefore, we also conducted a second series of docking runs that incorporated both NMR-PRE and NR restraints to better elucidate the conformations in this state. From these results, we were able to generate atomistic models for KRAS and KRAS/RAF1-RBD with averaged 1-D profiles closely matching the respective NR profiles. Overall, the findings should assist in elucidating the role of KRAS structural dynamics in recruiting effectors, like RAF kinase, to the membrane for activation.
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2021
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Chemical Modification of Bovine Milk Exosomes, the Biological Nanoparticles of the Future, as a Contrast Agent and Drug Delivery Vehicle
Chemically derived nanoparticles are widely used across many applications. While they showed great promise when first discovered, the main hurdles, such as clearance and targeting, have yet to be overcome. A recently discovered class of biological nanoparticles have the potential to circumvent these disadvantages. Exosomes are biological nanoparticles (30 – 150 nm) excreted from most mammalian cells. While exosomes are typically involved in cellular signaling and traditionally removed from the body to be examined for biomarkers, this work combines chemical modifications and a biological particle for diagnostics and treatment of solid tumor cancer. Exosome involvement in cancer treatment has grown over the past ten years with the encapsulation of RNA, proteins and traditional chemotherapeutics. However, this work takes these ideas and drives them into the future by using bovine milk derived exosomes as (1) an ultrasound contrasting agent and (2) a targeted and triggered chemotherapeutic drug delivery vehicle. As an ultrasound contrast agent, raw and pasteurized bovine milk exosomes were tested and found to be capable of echogenicity without altering the ability to identify key features of the exosome, including the presence of CD63 and miRNA. In the second part of this work a chemically synthesized, hypoxia responsive lipid and a tumor penetrating and targeting peptide, iRGD were integrated into the lipid bilayer of the exosome for chemotherapeutic drug delivery. These modified exosomes were characterized using a variety of techniques, including a novel adhesion assay, atomic force microscopy, and high-resolution transmission electron microscopy. The functional capacity of the modified exosomes to deliver doxorubicin to Triple Negative Breast Cancer (TNBC) cells was also evaluated using a combination of cellular internalization and cytotoxicity assays in both monolayer and 3D spheroid cultures. Overall exosomes have the iv ability to be chemically modified in a variety of ways, opening a door to a new approach to nanoparticle drug delivery and targeted imaging.
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2021
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Circulating Serum Exosomal Long Non-Coding RNAs FOXD2-AS1, NRIR, and XLOC_009459 as Diagnostic Biomarkers for Colorectal Cancer
Background: Exosomes derived from cancer cells encapsulate various kinds of tumor-specific molecules and thus can interact with adjacent or distant cells to mediate information exchange. Long non-coding RNAs (lncRNAs) in exosomes have the potential as diagnostic and prognostic biomarkers in different types of cancers. The current study was aimed to identify circulating exosomal lncRNAs for the diagnosis of colorectal cancer (CRC). Methods: Exosomes were isolated from the serum by ultracentrifugation and verified by transmission electron microscope (TEM), qNano, and immunoblotting. Exosomal lncRNAs FOXD2-AS1, NRIR, and XLOC_009459 were selected by lncRNA microarray and validated by qPCR in 203 CRC patients and 201 healthy donors. The receiver operating characteristic curve (ROC) was used to assess the diagnostic efficiency of serum exosomal lncRNAs. Results: Exosomal FOXD2-AS1, NRIR, and XLOC_009459 (TCONS_00020073) levels were significantly upregulated in 203 CRC patients and 80 early-stage CRC patients compared to 201 healthy donors, possessing the area under the curve (AUC) of 0.728, 0.660, and 0.682 for CRC, as well as 0.743, 0.660, and 0.689 for early-stage CRC, respectively. Notably, their combination demonstrated the markedly elevated AUC of 0.736 for CRC and 0.758 for early-stage CRC, indicating their potential as diagnostic biomarkers for CRC. Conclusions: Our data suggested that exosomal lncRNAs FOXD2-AS1, NRIR, and XLOC_009459 act as the promising biomarkers for the diagnostics of CRC and early-stage CRC.
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2021
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Comparison and optimization of nanoscale extracellular vesicle imaging by scanning electron microscopy for accurate size-based profiling and morphological analysis
Nanosized extracellular vesicles (EVs) have been found to play a key role in intercellular communication, offering opportunities for both disease diagnostics and therapeutics. However, lying below the diffraction limit and also being highly heterogeneous in their size, morphology and abundance, these vesicles pose significant challenges for physical characterization. Here, we present a direct visual approach for their accurate morphological and size-based profiling by using scanning electron microscopy (SEM). To achieve that, we methodically examined various process steps and developed a protocol to improve the throughput, conformity and image quality while preserving the shape of EVs. The study was performed with small EVs (sEVs) isolated from a non-small-cell lung cancer (NSCLC) cell line as well as from human serum, and the results were compared with those obtained from nanoparticle tracking analysis (NTA). While the comparison of the sEV size distributions showed good agreement between the two methods for large sEVs (diameter > 70 nm), the microscopy based approach showed a better capacity for analyses of smaller vesicles, with higher sEV counts compared to NTA. In addition, we demonstrated the possibility of identifying non-EV particles based on size and morphological features. The study also showed process steps that can generate artifacts bearing resemblance with sEVs. The results therefore present a simple way to use a widely available microscopy tool for accurate and high throughput physical characterization of EVs.
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2021
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Comparison of extracellular vesicle isolation and storage methods using high-sensitivity flow cytometry
Extracellular vesicles (EVs) are of interest for a wide variety of biomedical applications. A major limitation for the clinical use of EVs is the lack of standardized methods for the fast and reproducible separation and subsequent detection of EV subpopulations from biofluids, as well as their storage. To advance this application area, fluorescence-based characterization technologies with single-EV resolution, such as high-sensitivity flow cytometry (HS-FCM), are powerful to allow assessment of EV fractionation methods and storage conditions. Furthermore, the use of HS-FCM and fluorescent labeling of EV subsets is expanding due to the potential of high-throughput, multiplex analysis, but requires further method development to enhance the reproducibility of measurements. In this study, we have applied HS-FCM measurements next to standard EV characterization techniques, including nanoparticle tracking analysis, to compare the yield and purity of EV fractions obtained from lipopolysaccharide-stimulated monocytic THP-1 cells by two EV isolation methods, differential centrifugation followed by ultracentrifugation and the exoEasy membrane affinity spin column purification. We observed differences in EV yield and purity. In addition, we have investigated the influence of EV storage at 4°C or -80°C for up to one month on the EV concentration and the stability of EV-associated fluorescent labels. The concentration of the in vitro cell derived EV fractions was shown to remain stable under the tested storage conditions, however, the fluorescence intensity of labeled EV stored at 4°C started to decline within one day.
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2021
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Comparison of Syringes With Intravitreal Anti-VEGF Drugs: Particle Burden and Protein Aggregates in Brolucizumab, Aflibercept and Bevacizumab
Purpose: In a benchwork particle counting analytical evaluation, the number and type of particles in intravitreal injection formulations of three different agents against vascular endothelial growth factor were investigated. Methods: Commercially available ready-to-use aflibercept and brolucizumab glass syringes, vials containing bevacizumab (off-label use in ophthalmology), and repackaged ready-to-use plastic syringes containing bevacizumab were tested without filtration. Total visible, subvisible, and nanoparticles numbers and size distributions were quantified using light obscuration, flow imaging, resonant mass measurement (RMM), tunable resistive pulse sensing, and dynamic light scattering. Results: Repackaged bevacizumab showed overall low particle numbers, aflibercept showed high numbers of micrometer sized particles but low nanoparticle numbers, brolucizumab showed low to moderate numbers of micrometer sized particles but high nanoparticle numbers. RMM measurements identified particles in the nanometer range as either proteinaceous or silicon oil; the nature of the other particles was not further evaluated. Conclusions: Repackaged bevacizumab shows no inferior particle quality compared to ready-to-use products. It is relevant to study nanoparticle load of the products as the micrometer-sized particle numbers do not in all cases correlate to nanoparticle counts. Particularly for the high concentration product Beovu (brolucizumab), high nanoparticle numbers were found despite low numbers of micrometer sized particles. Silicone oil droplets did not account for high particle numbers as the measured numbers were low. Translational Relevance: Different side effects are registered in different frequencies with different intravitreal anti-VEGF-drugs and syringes, which are applied by injection by small 30G needles through the sclera directly to the intravitreal cavity. The study of nanoparticles and silicone oil droplets may be able to contribute to narrowing down the causes.
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2021
ev vr
Dancing with Trojan horses: an interplay between the extracellular vesicles and viruses
Extracellular vesicles (EVs) are membrane-encapsulated particles released by eukaryotic and prokaryotic cells into the extracellular environment. Depending on their origin, size, and composition, EVs are grouped in several classes, with one of them being exosomes, which are small EVs (SEVs) generated within the endosomal compartment of eukaryotic cells via the unique multivesicular body pathway. Being able to deliver their content (proteins, lipids, small molecules, and nucleic acids) to other cells, exosomes/SEVs are considered as bioactive vesicles with multiple biological functions. Importantly, the composition of exosomes/SEVs depends on the cell and tissue of origin including a set of specific proteins. However, the pathological conditions may lead to the appearance of diseases-specific exosomes/SEVs containing pathology-specific cargoes utilized in the malicious cell-cell communication and spread of malady. Viruses demonstrate complex ‘dancing’ around the exosome biogenesis system, being able to hijack the host systems responsible for the exosome biogenesis. They use the exosome biogenesis system to promote packaging of their capsids, regulate virion production, and virus secretion. They also utilize a Trojan horse stratagem to place virions inside the SEVs and thereby to spread beyond their normal range of cell hosts using the normal EV uptake process. Another illustration of the virus-based utilization of Trojan horse strategy is given by the ability of human viruses to use exosomes/SEVs as carriers of their exogenous miRNA or viral proteins to the non-infected cells. Taken together, these strategies of dancing with Trojan horses can help viruses to fight with the host defense and to spread the infection.
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2021
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Deciphering the Structure and Chemical Composition of Drug Nanocarriers: From Bulk Approaches to Individual Nanoparticle Characterization
Drug nanocarriers (NCs) with sizes usually below 200 nm are gaining increasing interest in the treatment of severe diseases such as cancer and infections. Characterization methods to investigate the morphology and physicochemical properties of multifunctional NCs are key in their optimization and in the study of their in vitro and in vivo fate. Whereas a variety of methods has been developed to characterize “bulk” NCs in suspension, the scope of this review is to describe the different approaches for the NC characterization on an individual basis, for which fewer techniques are available. The accent is put on methods devoid of labelling, which could lead to artefacts. For each characterization method, the principles and approaches to analyze the data are presented in an accessible manner. Aspects related to sample preparation to avoid artefacts are indicated, and emphasis is put on examples of applications. NC characterization on an individual basis allows gaining invaluable information in terms of quality control, on: i) NC localization and fate in biological samples; ii) NC morphology and crystallinity; iii) distribution of the NC components (drugs, shells), and iv) quantification of NCs’ chemical composition. The individual characterization approaches are expected to gain increasing interest in the near future.
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2021
ev nm vr
Development of a new methodology to determine size differences of nanoparticles with nanoparticle tracking analysis
The current frontiers in Biology thus in Medicine and Pharmacy are at the nanoscale. Indeed, this is the relevant scale for extracting or synthetizing, visualizing, counting, characterizing and/or modifying nanoparticles. Nanoparticles are highly diverse including: extracellular vesicles (e.g.: exosomes), proteins, viruses and nanovectors or drug delivery systems for instance. To quantify the concentration of nano-sized objects, a growing number of size-tracking instruments is being developed. However, to date, the generated data is only used to provide a concentration measurement. The objective of this study was to determine which sizes of nanoparticles are statistically significant between 2 groups of samples. Using different samples (in silico data; calibrated beads; various biological samples), an approach that statistically compares 2 groups of samples was developed and validated. The proof of concept of the proposed approach was illustrated with applications in the field of Biology, Medicine and Pharmacy using liposomes and extracellular vesicles. For the first time to our knowledge, our results suggest that the presented approach enables comparing different groups of biological samples. It may be extended to situations such as batch 1 versus batch 2; healthy versus disease or non-treated versus treated.
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2021
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Diagnostic potential of extracellular vesicle‑associated microRNA‑10b and tumor markers for lung adenocarcinoma
MicroRNAs (miRNAs/miRs) in extracellular vesicles (EVs) are potential diagnostic markers. The purpose of the present study was to investigate potential EV miRNA biomarkers for lung adenocarcinoma (LUAD). Potential miRNAs were identified by searching public databases and verified by examining clinical samples. The diagnostic value of EV‑associated miR‑10b, plasma miR‑10b and tumor markers (TMs), including α‑fetoprotein (AFP), neuron‑specific enolase, carcinoembryonic antigen (CEA), cytokeratin 19 fragment 21‑1 (CYFRA211), pro‑gastrin‑releasing‑peptide, carbohydrate antigen (CA)125, CA153, CA199 and CA724, was evaluated via receiver operating characteristic curve analysis. By searching the Gene Expression Omnibus and The Cancer Genome Atlas databases, miR‑10b was identified as a potential biomarker. The analysis of clinical samples suggested that EV‑associated miR‑10b from plasma was significantly differentially expressed between LUAD and control samples. EV‑associated miR‑10b could function as a diagnostic marker for LUAD, with an AUC of 0.998, which was higher than the AUCs for TMs such as AFP, CEA, CYFRA211, CA125, CA153, CA199, CA724, pro‑gastrin‑releasing‑peptide and neuron‑specific enolase. In conclusion, EV‑associated miR‑10b may be a potential diagnostic biomarker for LUAD that is superior to plasma miR‑10b and TMs.
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2021
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Effects of endurance racing on horse plasma extracellular particle miRNA
Background Physical exercise is an essential factor in preventing and treating metabolic diseases by promoting systemic benefits throughout the body. The molecular factors involved in this process are poorly understood. Micro RNAs (miRNAs) are small non‐coding RNAs that inhibit mRNA transcription. MiRNAs, which can participate in the benefits of exercise to health, circulate in plasma in extracellular particles (EP). Horses that undergo endurance racing are an excellent model to study the impact of long‐duration/low intensity exercise in plasma EP miRNAs. Objectives To evaluate the effects of 160 km endurance racing on horse plasma extracellular particles and their miRNA population. Study design Cohort study. Methods We collected plasma from 5 Arabian horses during five time‐points of an endurance ride. Extracellular particles were purified from plasma and characterised by electron microscopy, resistive pulse sensing (qNano), and western blotting. Small RNAs were purified from horse plasma EP, and sequencing was performed. Results Endurance racing increased EP concentration and average diameter compared to before the race. Western blotting showed a high concentration of extracellular vesicles proteins 2 h after the race, which returned to baseline 15 h after the race. MicroRNA differential expression analysis revealed increasing levels of eca‐miR‐486‐5p during and after the race, and decreasing levels of eca‐miR‐9083 after the end. Conclusions This study adds new data about the variation in plasma EP concentrations after long‐distance exercise and brings new insights about the roles of exercise‐derived EP miRNAs during low‐intensity endurance exercise.
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2021
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Effects of exercise on exosome release and cargo in in vivo and ex vivo models: A systematic review
Exercise-released exosomes have been identified as novel players to mediate cell-to-cell communication in promoting systemic beneficial effects. This review aimed to systematically investigate the effects of exercise on exosome release and cargo, as well as provide an overview of their physiological implications. Among the 436 articles obtained in the database search (WOS, Scopus, and PubMed), 19 articles were included based on eligibility criteria. Results indicate that exercise promotes the release of exosomes without modification of its vesicle size. The literature has primarily shown an exercise-driven increase in exosome markers (Alix, CD63, CD81, and Flot-1), along with other exosome-carried proteins, into circulation. However, exosome isolation, characterization, and phenotyping methodology, as well as timing of sample recovery following exercise can influence the analysis and interpretation of findings. Moreover, a large number of exosome-carried microRNAs (miRNAs), including miR-1, miR-133a, miR-133b, miR-206, and miR-486, in response to exercise are involved in the modulation of proliferation and differentiation of skeletal muscle tissue, although antigen-presenting cells, leukocytes, endothelial cells, and platelets are the main sources of exosome release into the circulation. Collectively, with the physiological implications as evidenced by the ex vivo trials, the release of exercise-promoted exosomes and their cargo could provide the potential therapeutic applications via the role of intercellular communication.
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2021
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Effects of exosomes derived from human umbilical vein endothelial cells on apoptosis of pre-chondrogenic cells stimulated by inflammatory factors
·To investigate the effect of exosomes derived from umbilical vein endothelial cells (HUVECs) on apoptosis of murine pre-chondrogenic cell line ATDC5 cells under inflammatory stimulation. ·The exosomes derived from HUVECs were isolated by using an exosome isolation kit. Western blotting was used to detect the exosome marker proteins, including tumor susceptibility gene 101 (Tsg101), cluster differentiation 9 (CD9) and apoptosis linked gene-2-interacting protein X (Alix). The morphology of exosomes was observed by transmission electron microscope, and the size of exosomes was identified by particle size detection. Fluorescence microscope was used to observe the ATDC5 cell uptake of exosomes and the production of reactive oxygen species (ROS). TUNEL staining and flow cytometry were used to examine the effect of exosomes on ATDC5 cell apoptosis stimulated by interleukin-1β (IL-1β). Western blotting was used to detect the effect of exosomes on the expression levels of ATDC5 apoptosis-related proteins such as B-cell lymphoma/leukemia 2 (Bcl-2), Bcl-2 associated X protein (Bax), cleaved caspase-3 (c-caspase-3) and anti-oxidative stress-related proteins such as nuclear factor E2 related factor 2 (Nrf-2), Kelch-like ECH-associated protein 1 (Keap-1), heme oxygenase 1 (HO-1) and NADPH quinone oxidoreductase-like protein 1 (NQO-1) under IL-1β stimulation. ·Under the transmission electron microscope, the HUVEC-derived exosomes were oval, hollow, double-layered, and positively expressed exosome markers CD9, Alix and Tsg101. Compared with the ATDC5 cells stimulated by IL-1β, ATDC5 cells stimulated by IL-1β incubated with exosomes had higher level of ROS (P=0.000) and higher apoptosis rate (P=0.000). The expression of Bax, c-caspase-3 and Keap-1 increased, and the expression of Bcl-2, Nrf-2, HO-1 and NQO-1 decreased in ATDC5 cells exposed to IL-1β and exosomes compared to ATDC5 cells only exposed to IL-1β. ·HUVEC-derived exosomes may promote ATDC5 cells apoptosis under the stimulation of IL-1β by inhibiting the ability of ATDC5 cell to resist oxidative stress.
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2021
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Effects of Solidification Conditions on Grain Refinement Capacity of TiC in Directionally Solidified Ti6Al4V Alloy
In this study, the effects of solidification conditions on the grain refinement capacity of heterogeneous nuclei TiC in directionally solidified Ti6Al4V alloy were investigated using experimental and numerical approaches. Ti6Al4V powder with and without TiC particles in a Ti6Al4V sheath was melted and directionally solidified at various solidification rates via the floating zone melting method. In addition, by using the phase field method, the microstructural evolution of directionally solidified Ti6Al4V was simulated by varying the temperature gradient G and solidification rate V. As the solidification rate increased, the increment of the prior β grain number by TiC addition also increased. There are two reasons for this: first, the amount of residual potent heterogeneous nuclei TiC is larger. Second, the amount of TiC particles that can nucleate becomes larger. This is because increasing the constitutional undercooling ΔTc leads to the activation of a smaller radius of heterogeneous nuclei and a higher nucleation probability from each radius. At a cooling rate R higher than that in the floating zone melting experiment (R = 3 to 1000 K/s), the maximum degree of constitutional undercooling ΔTc,Max has a peak value, which suggests that constitutional undercooling ΔTc has a smaller contribution at higher cooling rates, such as those that occur during electron beam melting (EBM), including laser powder bed fusion (LPBF).
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2021
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Embryonic stem cell-derived exosomes attenuate transverse aortic constriction induced heart failure by increasing angiogenesis
Background: Although there are concerns regarding their clinical use, embryonic stem cells (ESCs) hold a great promise for cardiac repair. Exosomes deriving from ESCs constitute a promising alternative for heart restoration. However, their effects in hypertension-induced heart failure are still unknown. Objective and Methods: To investigate the effects of ESCs-derived exosomes on hypertension-induced heart failure and the underlying mechanisms, sustained transverse aortic constriction (TAC) was performed on 8-week-old C57BL/6 male mice. After 1 months, ESCs-derived exosomes were isolated and injected intravenously once a week for 6 weeks. Echocardiography, wheat germ agglutinin (WGA), Masson staining, immunohistochemistry, and tube formation assays were all involved in our study. Results: Proteomics analyses revealed that ESC-derived exosomes contain FGF2 protein. Tube formation induced by these exosomes could be inhibited by FGF2R siRNA interference. ESCs-derived exosomes evidently attenuated TAC-induced heart failure, improving cardiac function and promoting myocardial angiogenesis which can be attenuated by selective FGF2 inhibitor AZD4547. Conclusions: ESC-derived exosomes attenuate TAC-induced heart failure mostly by promoting myocardial angiogenesis. FGF2 signaling plays a vital role in the myocardial angiogenesis induced by ESC-derived exosomes. Keywords: embryonic stem cells, exosomes, angiogenesis, transverse aortic constriction, heart failure
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2021
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Endothelial Progenitor Cell-Derived Extracellular Vesicles: Potential Therapeutic Application in Tissue Repair and Regeneration
Recently, many studies investigated the role of a specific type of stem cell named the endothelial progenitor cell (EPC) in tissue regeneration and repair. EPCs represent a heterogeneous population of mononuclear cells resident in the adult bone marrow. EPCs can migrate and differentiate in injured sites or act in a paracrine way. Among the EPCs’ secretome, extracellular vesicles (EVs) gained relevance due to their possible use for cell-free biological therapy. They are more biocompatible, less immunogenic, and present a lower oncological risk compared to cell-based options. EVs can efficiently pass the pulmonary filter and deliver to target tissues different molecules, such as micro-RNA, growth factors, cytokines, chemokines, and non-coding RNAs. Their effects are often analogous to their cellular counterparts, and EPC-derived EVs have been tested in vitro and on animal models to treat several medical conditions, including ischemic stroke, myocardial infarction, diabetes, and acute kidney injury. EPC-derived EVs have also been studied for bone, brain, and lung regeneration and as carriers for drug delivery. This review will discuss the pre-clinical evidence regarding EPC-derived EVs in the different disease models and regenerative settings. Moreover, we will discuss the translation of their use into clinical practice and the possible limitations of this process.
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2021
ev nm vr
Enhancing the Stabilization Potential of Lyophilization for Extracellular Vesicles
Extracellular vesicles (EV) are an emerging technology as immune therapeutics and drug delivery vehicles. However, EVs are usually stored at −80 °C which limits potential clinical applicability. Freeze-drying of EVs striving for long-term stable formulations is therefore studied. The most appropriate formulation parameters are identified in freeze-thawing studies with two different EV types. After a freeze-drying feasibility study, four lyophilized EV formulations are tested for storage stability for up to 6 months. Freeze-thawing studies revealed improved colloidal EV stability in presence of sucrose or potassium phosphate buffer instead of sodium phosphate buffer or phosphate-buffered saline. Less aggregation and/or vesicle fusion occurred at neutral pH compared to slightly acidic or alkaline pH. EVs colloidal stability can be most effectively preserved by addition of low amounts of poloxamer 188. Polyvinyl pyrrolidone failed to preserve EVs upon freeze-drying. Particle size and concentration of EVs are retained over 6 months at 40 °C in lyophilizates containing 10 mm K- or Na-phosphate buffer, 0.02% poloxamer 188, and 5% sucrose. The biological activity of associated beta-glucuronidase is maintained for 1 month, but decreased after 6 months. Here optimized parameters for lyophilization of EVs that contribute to generate long-term stable EV formulations are presented.
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2021
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Enzymatically active apurinic/apyrimidinic endodeoxyribonuclease 1 is released by mammalian cells through exosomes
The apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1), the main AP-endonuclease of the DNA base excision repair pathway, is a key molecule of interest to researchers due to its unsuspected roles in different nonrepair activities, such as: i) adaptive cell response to genotoxic stress, ii) regulation of gene expression, and iii) processing of microRNAs, which make it an excellent drug target for cancer treatment. We and others recently demonstrated that APE1 can be secreted in the extracellular environment and that serum APE1 may represent a novel prognostic biomarker in hepatocellular and non-small-cell lung cancers. However, the mechanism by which APE1 is released extracellularly was not described before. Here, using three different approaches for exosomes isolation: commercial kit, nickel-based isolation, and ultracentrifugation methods and various mammalian cell lines, we elucidated the mechanisms responsible for APE1 secretion. We demonstrated that APE1 p37 and p33 forms are actively secreted through extracellular vesicles (EVs), including exosomes from different mammalian cell lines. We then observed that APE1 p33 form is generated by proteasomal-mediated degradation and is enzymatically active in EVs. Finally, we revealed that the p33 form of APE1 accumulates in EVs upon genotoxic treatment by cisplatin and doxorubicin, compounds commonly found in chemotherapy pharmacological treatments. Taken together, these findings provide for the first time evidence that a functional Base Excision Repair protein is delivered through exosomes in response to genotoxic stresses, shedding new light into the complex noncanonical biological functions of APE1 and opening new intriguing perspectives on its role in cancer biology.
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2021
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Estradiol driven metabolism in transwomen associates with reduced circulating extracellular vesicle microRNA-224/452
Objective Sex steroid hormones like estrogens have a key role in the regulation of energy homeostasis and metabolism. In transwomen, gender-affirming hormone therapy like estradiol (in combination with antiandrogenic compounds) could affect metabolism as well. Given that the underlying pathophysiological mechanisms are not fully understood, this study assessed circulating estradiol-driven microRNAs (miRs) in transwomen and their regulation of genes involved in metabolism in mice. Methods Following plasma miR-sequencing (seq) in a transwomen discovery (n = 20) and validation cohort (n = 30), we identified miR-224 and miR-452. Subsequent systemic silencing of these miRs in male C57Bl/6 J mice (n = 10) was followed by RNA-seq-based gene expression analysis of brown and white adipose tissue in conjunction with mechanistic studies in cultured adipocytes. Results Estradiol in transwomen lowered plasma miR-224 and -452 carried in extracellular vesicles (EVs) while their systemic silencing in mice and cultured adipocytes increased lipogenesis (white adipose) but reduced glucose uptake and mitochondrial respiration (brown adipose). In white and brown adipose tissue, differentially expressed (miR target) genes are associated with lipogenesis (white adipose) and mitochondrial respiration and glucose uptake (brown adipose). Conclusion This study identified an estradiol-drive post-transcriptional network that could potentially offer a mechanistic understanding of metabolism following gender-affirming estradiol therapy.
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2021
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Evaluating comparative β-glucan production aptitude of Saccharomyces cerevisiae, Aspergillus oryzae, Xanthomonas campestris, and Bacillus natto
β-glucan is a natural polysaccharide derivative composed of a group of glucose monomers with β-glycoside bonds that can be synthesized intra- or extra-cellular by various microorganisms such as yeasts, bacteria, and moulds. The study aimed to discover the potential of various microorganisms such as Saccharomyces cerevisiae, Aspergillus oryzae, Xanthomonas campestris, and Bacillus natto in producing β-glucan. The experimental method used and the data were analyzed descriptively. The four microorganisms above were cultured under a submerged state in Yeast glucose (YG) broth for 120 h at 30 °C with 200 rpm agitation. During the growth, several parameters were examined including total population by optical density, the pH, and glucose contents of growth media. β-glucan was extracted using acid-alkaline methods from the growth media then the weight was measured. The results showed that S. cerevisiae, A. oryzae X. campestris, and B. natto were prospective for β-glucans production in submerged fermentation up to 120 h. The highest β-glucans yield was shown by B. natto (20.38%) with the β-glucans mass of 1.345 ± 0.08 mg and globular diameter of 600 μm. The highest β-glucan mass was achieved by A. oryzae of 82.5 ± 0.03 mg with the total population in optical density of 0.1246, a final glucose level of 769 ppm, the pH of 6.67, and yield of 13.97% with a globular diameter of 1400 μm.
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2021
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Exosomal CD47 plays an essential role in immune evasion in ovarian cancer
Ovarian cancer is largely diagnosed at advanced stages upon detection of multiple peritoneal dissemination, resulting in poor outcomes. CD47 is overexpressed in tumors, facilitates tumor immune evasion, and is located on exosomes. We aimed to investigate the role of exosomal CD47 in ovarian cancer progression. Prognostic significance of CD47 expression in ovarian cancer was examined using a public database including 1,435 patients and validated with 26 patients at our institution. CD47 expression was associated with poor progression-free survival and inversely correlated with macrophage infiltration in ovarian cancer tissues. Exosomes were collected from ovarian cancer cell lines, and CD47 expression on exosomes was confirmed via flow cytometry. Inhibition of exosome secretion with GW4869 and exosome uptake with 5-(N-ethyl-N-isopropyl)-amiloride inhibited the surface CD47 expression on ovarian cancer cells and promoted phagocytosis by macrophages. RAB27A (a key regulator of exosome release) knockdown inhibited exosome secretion and led to CD47 downregulation in ovarian cancer cells. In a xenograft mouse model, suppression of the release of tumor-derived exosomes by GW4869 or RAB27A knockdown suppressed tumor progression and enhanced M1 macrophage phagocytosis in cancer tissues. Collectively, CD47 expression was correlated with poor prognoses in patients with ovarian cancer, suggesting the importance of immune evasion. CD47 was expressed on exosomes and the inhibition of exosome secretion and/or uptake enhanced cancer cell phagocytosis by macrophages, and thus, suppressed peritoneal dissemination. This suggests the potential of a novel immune checkpoint therapeutic agent that focuses on exosomes. Implications: Mechanistic insight from the current study suggests that exosomal CD47 may be an advantageous therapeutic target in ovarian cancer.
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2021
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Exosome-Depleted Excretory-Secretory Products of the Fourth-Stage Larval Angiostrongylus cantonensis Promotes Alternative Activation of Macrophages Through Metabolic Reprogramming by the PI3K-Akt Pathway
Angiostrongylus cantonensis (AC), which parasitizes in the brain of the non-permissive host, such as mouse and human, is an etiologic agent of eosinophilic meningitis. Excretory-secretory (ES) products play an important role in the interaction between parasites and hosts’ immune responses. Inflammatory macrophages are responsible for eosinophilic meningitis induced by AC, and the soluble antigens of Angiostrongylus cantonensis fourth stage larva (AC L4), a mimic of dead AC L4, aggravate eosinophilic meningitis in AC-infected mice model via promoting alternative activation of macrophages. In this study, we investigated the key molecules in the ES products of AC L4 on macrophages and observed the relationship between metabolic reprogramming and the PI3K-Akt pathway. First, a co-culture system of macrophage and AC L4 was established to define the role of AC L4 ES products on macrophage polarization. Then, AC L4 exosome and exosome-depleted excretory-secretory products (exofree) were separated from AC L4 ES products using differential centrifugation, and their distinct roles on macrophage polarization were confirmed using qPCR and ELISA experiments. Moreover, AC L4 exofree induced alternative activation of macrophages, which is partially associated with metabolic reprogramming by the PI3K-Akt pathway. Next, lectin blot and deglycosylation assay were done, suggesting the key role of N-linked glycoproteins in exofree. Then, glycoproteomic analysis of exofree and RNA-seq analysis of exofree-treated macrophage were performed. Bi-layer PPI network analysis based on these results identified macrophage-related protein Hexa as a key molecule in inducing alternative activation of macrophages. Our results indicate a great value for research of helminth-derived immunoregulatory molecules, which might contribute to drug development for immune-related diseases. Keywords: Angiostrongylus cantonensis, exosome-depleted excretory-secretory products, N-linked glycoproteins, macrophage polarization, mechanism
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2021
ev vr
Exosomes released by imatinib‑resistant K562 cells contain specific membrane markers, IFITM3, CD146 and CD36 and increase the survival of imatinib‑sensitive cells in the presence of imatinib
Chronic myeloid leukemia (CML) is a malignant hematopoietic disorder distinguished by the presence of a BCR‑ABL1 fused oncogene with constitutive kinase activity. Targeted CML therapy by specific tyrosine kinase inhibitors (TKIs) leads to a marked improvement in the survival of the patients and their quality of life. However, the development of resistance to TKIs remains a critical issue for a subset of patients. The most common cause of resistance are numerous point mutations in the BCR‑ABL1 gene, followed by less common mutations and multiple mutation-independent mechanisms. Recently, exosomes, which are extracellular vesicles excreted from normal and tumor cells, have been associated with drug resistance and cancer progression. The aim of the present study was to characterize the exosomes released by imatinib‑resistant K562 (K562IR) cells. The K562IR‑derived exosomes were internalized by imatinib‑sensitive K562 cells, which thereby increased their survival in the presence of 2 µM imatinib. The exosomal cargo was subsequently analyzed to identify resistance‑associated markers using a deep label‑free quantification proteomic analysis. There were >3,000 exosomal proteins identified of which, 35 were found to be differentially expressed. From this, a total of 3, namely the membrane proteins, interferon‑induced transmembrane protein 3, CD146 and CD36, were markedly upregulated in the exosomes derived from the K562IR cells, and exhibited surface localization. The upregulation of these proteins was verified in the K562IR exosomes, and also in the K562IR cells. Using flow cytometric analysis, it was possible to further demonstrate the potential of CD146 as a cell surface marker associated with imatinib resistance in K562 cells. Taken together, these results suggested that exosomes and their respective candidate surface proteins could be potential diagnostic markers of TKI drug resistance in CML therapy.
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2021
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Exosomes‐mediated transfer of long noncoding RNA LINC01133 represses bladder cancer progression via regulating the Wnt signaling pathway
Bladder cancer (BC), as one of the most common malignant cancers of the urinary system, has a high incidence and mortality rates. Recently, increasing studies have indicated that exosomes can mediate cellular communication in assorted cancers, including BC. Long noncoding RNAs (lncRNAs) have also been confirmed to take part in the regulation of many cancers. Long intergenic non-protein coding RNA 1133 (LINC01133) is an lncRNA and its roles in several cancers have been revealed. However, the functions of exosomes and LINC01133 in BC are still not elucidated. In our research, functional assays were conducted to evaluate the function of LINC01133, as well as the influence of exosomes and LINC01133 on BC cells. Western blot assay, immunofluorescence assay, electron microscope, and nanoparticle tracking analysis were applied for detecting the characteristics of exosomes. Bioinformatics tools and quantitative reverse-transcription polymerase chain reaction were performed to test the expression of LINC01133 in BC cells and exosomes of the immortalized human uroepithelial cell line (SV-HUC-1). Luciferase reporter assay was performed to measure the activity of the Wnt pathway. We discovered that LINC01133 expression was high in exosomes of SV-HUC-1 and low in that of BC cells. Additionally, exosomes restrained cell viability, proliferation, migration, and invasion. Similarly, LINC01133 exerted the same function on BC cells. In addition, the Wnt signaling pathway could be inactivated by LINC01133. Finally, in vivo experiments demonstrated that cell growth could be suppressed by overexpressed LINC01133. In short, exosomes-mediated transfer of lncRNA LINC01133 repressed BC progression via regulating the Wnt signaling pathway.
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2021
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Extracellular Vesicles as an Emerging Treatment Option for Intervertebral Disc Degeneration: Therapeutic Potential, Translational Pathways, and Regulatory Considerations
Emergent approaches in regenerative medicine look toward the use of extracellular vesicles (EVs) as a next-generation treatment strategy for intervertebral disc (IVD) degeneration (IVDD) because of their ability to attenuate chronic inflammation, reduce apoptosis, and stimulate proliferation in a number of tissue systems. Yet, there are no Food and Drug Administration (FDA)-approved EV therapeutics in the market with an indication for IVDD, which motivates this article to review the current state of the field and provide an IVD-specific framework to assess its efficacy. In this systematic review, 29 preclinical studies that investigate EVs in relation to the IVD are identified, and additionally, the regulatory approval process is reviewed in an effort to accelerate emerging EV-based therapeutics toward FDA submission and timeline-to-market. The majority of studies focus on nucleus pulposus responses to EV treatment, where the main findings show that stem cell-derived EVs can decelerate the progression of IVDD on the molecular, cellular, and organ level. The findings also highlight the importance of the EV parent cell's pathophysiological and differentiation state, which affects downstream treatment responses and therapeutic outcomes. This systematic review substantiates the use of EVs as a promising cell-free strategy to treat IVDD and enhance endogenous repair.
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2021
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Extracellular vesicles derived from T-cell acute lymphoblastic leukemia inhibit osteogenic differentiation of bone marrow mesenchymal stem cells via miR-34a-5p
Reduced bone formation in patients with T-cell acute lymphoblastic leukemia (T-ALL) may be related to the interaction between tumour cells and bone marrow stromal cells (BMSCs). The miRNAs in extracellular vesicles derived from leukemia cells play an essential role in regulating the function of BMSCs; however, the regulatory mechanisms remain unclear. The expression of miR-34a-5p in T-ALL patients and cells was measured by quantitative real-time PCR. BMSCs were co-cultured with extracellular vesicles isolated from T-ALL cells in mineralization medium. The osteogenic differentiation of BMSCs was evaluated by Alizarin Red S staining, alkaline phosphatase (ALP) staining, and detection of osteogenic differentiation markers. A dual-luciferase reporter assay was performed to confirm the targeting relationship between miR-34a-5p and Wnt family member 1 (WNT1). MiR-34a-5p expression was upregulated in T-ALL patients and Jurkat cells. After BMSCs were co-cultured with extracellular vesicles derived from T-ALL cells, osteogenic differentiation of BMSCs was inhibited, and bone mineralization and ALP activity were decreased compared to those of control cells. MiR-34a-5p knockdown in T-ALL cells restored osteogenic differentiation of BMSCs co-cultured with extracellular vesicles. In addition, miR-34a-5p targets and negatively regulates WNT1 expression. In conclusion, our results demonstrated that knockdown of miR-34a-5p in extracellular vesicles derived from T-ALL cells promoted osteogenic differentiation of BMSCs by regulating WNT1.
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2021
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Extracellular Vesicles from Thapsigargin-Treated Mesenchymal Stem Cells Ameliorated Experimental Colitis via Enhanced Immunomodulatory Properties
Therapeutic applications of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) have attracted considerable attention because of their immunomodulatory properties against immune-mediated, inflammatory diseases. Here, we demonstrated enhanced immunomodulatory properties of EVs secreted from endoplasmic reticulum (ER) stress inducer thapsigargin (TSG)-primed human Wharton’s jelly-derived MSCs (WJ-MSCs). EVs from TSG-primed WJ-MSCs (TSG-EV) showed increased yield and expression of immunomodulatory factors, such as transforming growth factor-β1 (TGFβ), cyclooxygenase-2 (COX2), and especially indoleamine 2,3-dioxygenase (IDO), compared to control EVs. TSG-EV showed a significantly enhanced immunosuppressive effect on human peripheral blood-derived T cell proliferation and Th1 and Th17 differentiation, whereas Treg and M2-type macrophage were enriched compared to a control EV-treated group. Furthermore, TSG-EV substantially mitigated mouse experimental colitis by reducing the inflammatory response and maintaining intestinal barrier integrity. A significant increase of Tregs and M2-type macrophages in colitic colons of a TSG-EV-treated mouse suggests an anti-inflammatory effect of TSG-EV in colitis model, possibly mediated by Treg and macrophage polarization. These data indicate that TSG treatment promoted immunomodulatory properties of EVs from WJ-MSCs, and TSG-EV may provide a new therapeutic approach for treatment of colitis.
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2021
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Extracellular vesicles secreted by mesenchymal stromal cells exert opposite effects to their cells of origin in murine sodium dextran sulfate-induced colitis
Several reports have described a beneficial effect of Mesenchymal Stromal Cells (MSCs) and of their secreted extracellular vesicles (EVs) in mice with experimental colitis. However, the effects of the two treatments have not been thoroughly compared in this model. Here, we compared the effects of MSCs and of MSC-EV administration in mice with colitis induced by dextran sulfate sodium (DSS). Since cytokine conditioning was reported to enhance the immune modulatory activity of MSCs, the cells were kept either under standard culture conditions (naïve, nMSCs) or primed with a cocktail of pro-inflammatory cytokines, including IL1β, IL6 and TNFα (induced, iMSCs). In our experimental conditions, nMSCs and iMSCs administration resulted in both clinical and histological worsening and was associated with pro-inflammatory polarization of intestinal macrophages. However, mice treated with iEVs showed clinico-pathological improvement, decreased intestinal fibrosis and angiogenesis and a striking increase in intestinal expression of Mucin 5ac, suggesting improved epithelial function. Moreover, treatment with iEVs resulted in the polarization of intestinal macrophages towards and anti-inflammatory phenotype and in an increased Treg/Teff ratio at the level of the intestinal lymph node. Collectively, these data confirm that MSCs can behave either as anti- or as pro-inflammatory agents depending on the host environment. In contrast, EVs showed a beneficial effect, suggesting a more predictable behavior, a safer therapeutic profile and a higher therapeutic efficacy with respect to their cells of origin. Keywords: inflammatory bowel disease, mesenchymal stromal cells, extracellular vesicles, macrophage polarization, sodium dextran sulfate, immunomodulation
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2021
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Extracellular vesicles shed by follicular lymphoma B cells promote the polarization of bone marrow stromal cell niche
Follicular lymphoma (FL) originates in the lymph nodes (LNs) and infiltrates bone marrow (BM) early in the course of the disease. BM FL B cells are characterized by a lower cytological grade, decreased proliferation, and a specific phenotypic and subclonal profile. Mesenchymal stromal cells (MSCs) obtained from FL BM display a specific gene expression profile (GEP), including enrichment for a lymphoid stromal cell signature, and an increased capacity to sustain FL B-cell growth. However, the mechanisms triggering the formation of the medullar FL permissive stromal niche have not been identified. In the current work, we demonstrate that FL B cells produce extracellular vesicles (EVs) that can be internalized by BM-MSCs, making them more efficient to support FL B-cell survival and quiescence. Accordingly, EVs purified from FL BM plasma activate transforming growth factor β–dependent and independent pathways in BM-MSCs and modify their GEP, triggering an upregulation of factors classically associated with hematopoietic stem cell niche, including CXCL12 and angiopoietin-1. Moreover, we provide the first characterization of BM FL B-cell GEP, allowing the definition of the landscape of molecular interactions they could engage with EV-primed BM-MSCs. This work identifies FL-derived EVs as putative mediators of BM stroma polarization and supports further investigation of their clinical interest for targeting the crosstalk between BM-MSCs and malignant B cells.
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2021
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FO‐SPR biosensor calibrated with recombinant extracellular vesicles enables specific and sensitive detection directly in complex matrices
Extracellular vesicles (EVs) have drawn huge attention for diagnosing myriad of diseases, including cancer. However, the EV detection and analyses procedures often lack much desired sample standardization. To address this, we used well-characterized recombinant EVs (rEVs) for the first time as a biological reference material in developing a fiber optic surface plasmon resonance (FO-SPR) bioassay. In this context, EV binding on the FO-SPR probes was achieved only with EV-specific antibodies (e.g. anti-CD9 and anti-CD63) but not with non-specific anti-IgG. To increase detection sensitivity, we tested six different combinations of EV-specific antibodies in a sandwich bioassay. Calibration curves were generated with two most effective combinations (anti-CD9/Banti-CD81 and anti-CD63/Banti-CD9), resulting in 103 and 104 times higher sensitivity than the EV concentration in human blood plasma from healthy or cancer patients, respectively. Additionally, by using anti-CD63/Banti-CD9, we detected rEVs spiked in cell culture medium and HEK293 endogenous EVs in the same matrix without any prior EV purification or enrichment. Lastly, we selectively captured breast cancer cell EVs spiked in blood plasma using anti-EpCAM antibody on the FO-SPR surface. The obtained results combined with FO-SPR real-time monitoring, fast response time and ease of operation, demonstrate its outstanding potential for EV quantification and analysis.
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2021
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Formulation and characterization of phytostanol ester solid lipid nanoparticles for the management of hypercholesterolemia: an ex vivo study
Background Phytostanols are naturally occurring compounds that reduce blood cholesterol levels significantly. However, their aqueous insolubility poses formulation challenges. Aim To formulate and characterize solid lipid nanoparticle carriers for phytostanol esters to enhance the bioavailability of phytostanols. Methods Phytostanol ester solid lipid nanoparticles were formulated by the microemulsion method. They were characterized for particle size distribution, polydispersity index, shape, surface charge, entrapment efficiency, stability, chemical structure, and thermal properties. The uptake of the formulation by cell lines, HepG2 and HT-29, and its effect on cell viability were evaluated. Results The formulation of solid lipid nanoparticles was successfully optimised by varying the type of lipids and their concentration relative to that of surfactants in the present study. The optimised formulation had an average diameter of (171 ± 9) nm, a negative surface charge of (−23.0 ± 0.8) mV and was generally spherical in shape. We report high levels of drug entrapment at (89 ± 5)% in amorphous form, drug loading of (9.1 ± 0.5)%, nanoparticle yield of (67 ± 4)% and drug excipient compatibility. The biological safety and uptake of the formulations were demonstrated on hepatic and intestinal cell lines. Conclusion Phytostanol ester solid lipid nanoparticles were successfully formulated and characterized. The formulation has the potential to provide an innovative drug delivery system for phytostanols which reduce cholesterol and have a potentially ideal safety profile. This can contribute to better management of one of the main risk factors of cardiovascular diseases. Keywords: cardiovascular diseases, cholesterol, phytostanol ester, PSE, solid lipid nanoparticles, SLNPs, hypercholesterolemia
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2021
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Fractionnement et caractérisation de nanoparticules par une méthode hydrodynamique: modélisation et application aux produits de consommation
L’augmentation de l’utilisation des nanoparticules au fil des années rend nécessaire une meilleure compréhension de leurs propriétés, leur devenir dans l’environnement ainsi que leur impact sur la santé. A cette fin, de meilleures techniques de caractérisation nécessitent d’être développées. Parmi les différentes propriétés des nanoparticules, la taille est particulièrement importante car elle influence de nombreuses propriétés (comme, par exemple : la réactivité, la toxicité ou leur capacité de migration dans l’environnement). Parmi les nombreuses techniques de caractérisation en taille existantes, le fractionnement par couplage flux force asymétrique (AF4) est une technique qui permet de séparer les différentes populations de nanoparticules présentes dans l’échantillon en fonction de leur diamètre hydrodynamique avant de les envoyer à un détecteur en taille. Ce fractionnement permet de simplifier le travail du détecteur.Dans les années 1960, un modèle (appelé dans la thèse modèle classique) reliant le temps de rétention des nanoparticules au sein de l’AF4 à leur diamètre hydrodynamique a été développé. Cependant la validité du modèle repose sur des hypothèses de travail qui ne sont pas toujours respectées dans certaines conditions expérimentales.Ces travaux ont consisté, dans un premier temps, à étudier les mécanismes gouvernant la rétention au sein de l’AF4. Il a été montré que des interactions entre les nanoparticules et la paroi du canal biaisent les résultats prédits par le modèle classique. Un autre modèle (appelé dans la thèse modèle p-w) prenant en compte les interactions électrostatiques et de van der Waals a été étudié. Le modèle p-w s’est montré plus robuste que le modèle classique. Une validation de ce modèle a été conduite et un bilan d’incertitude a été développé en utilisant la méthode de Monte- Carlo. La traçabilité métrologique des résultats de mesure a également été démontrée.Ces travaux ont consisté, dans un premier temps, à étudier les mécanismes gouvernant la rétention au sein de l’AF4. Il a été montré que des interactions entre les nanoparticules et la paroi du canal biaisent les résultats prédits par le modèle classique. Un autre modèle (appelé au cours de la thèse modèle p-w) prenant en compte les interactions électrostatiques et de van der Waal a été étudié. Le modèle p-w s’est montré plus robuste que le modèle classique. Une validation de ce modèle a été conduite et un bilan d’incertitude a été développé en utilisant la méthode de Monte- Carlo. La traçabilité métrologique des résultats de mesure a été démontrée.
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2021
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High throughput imaging of nanoscale extracellular vesicles by scanning electron microscopy for accurate size-based profiling and morphological analysis.
Nanoscale extracellular vesicle (EVs) have been found to play a key role in intercellular communication, offering opportunities for both diagnostics and therapeutics. However, lying below the diffraction limit and also being highly heterogeneous in their size, morphology and abundance, these vesicles pose significant challenges for their physical characterization. Here, we present a direct visual approach for their accurate morphological and size-based profiling by using scanning electron microscopy (SEM). To achieve that, we methodically examined various process steps and developed a protocol to improve the throughput, conformity and image quality while preserving the shape of EVs. The investigation was performed with small EVs (sEVs) isolated from a non-small cell lung cancer (NSCLC) cell line H1975 as well as from a human serum, and the results were compared with those obtained from nanoparticle tracking analysis (NTA). While the comparison of the sEV size distributions showed good agreement between the two methods for large sEVs (diameter >70 nm), the microscopy based approach showed a better capacity for analyses on smaller vesicles, with higher sEV counts compared to NTA. In addition, we demonstrated the possibility of identifying non-EV particles based on size and morphological features. The study also showed process steps that can generate artifacts bearing resemblance with sEVs. The results therefore present a simple way to use a widely available microscopy tool for accurate and high throughput physical characterization of EVs.
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2021
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High-Sensitivity Glycan Profiling of Blood-Derived Immunoglobulin G, Plasma, and Extracellular Vesicle Isolates with Capillary Zone Electrophoresis-Mass Spectrometry
We developed a highly sensitive method for profiling of N-glycans released from proteins based on capillary zone electrophoresis coupled to electrospray ionization mass spectrometry (CZE-ESI-MS) and applied the technique to glycan analysis of plasma and blood-derived isolates. The combination of dopant-enriched nitrogen (DEN)-gas introduced into the nanoelectrospray microenvironment with optimized ionization, desolvation, and CZE-MS conditions improved the detection sensitivity up to ∼100-fold, as directly compared to the conventional mode of instrument operation through peak intensity measurements. Analyses without supplemental pressure increased the resolution ∼7-fold in the separation of closely related and isobaric glycans. The developed method was evaluated for qualitative and quantitative glycan profiling of three types of blood isolates: plasma, total serum immunoglobulin G (IgG), and total plasma extracellular vesicles (EVs). The comparative glycan analysis of IgG and EV isolates and total plasma was conducted for the first time and resulted in detection of >200, >400, and >500 N-glycans for injected sample amounts equivalent to <500 nL of blood. Structural CZE-MS2 analysis resulted in the identification of highly diverse glycans, assignment of α-2,6-linked sialic acids, and differentiation of positional isomers. Unmatched depth of N-glycan profiling was achieved compared to previously reported methods for the analysis of minute amounts of similar complexity blood isolates.
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2021
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Human mesenchymal stromal cells small extracellular vesicles attenuate sepsis-induced acute lung injury in a mouse model: the role of oxidative stress and the mitogen-activated protein kinase/nuclear factor kappa B pathway
Background aims Acute lung injury (ALI) secondary to sepsis is a complex disease associated with high morbidity and mortality. Mesenchymal stem cells (MSCs) and their conditioned medium have been demonstrated to reduce alveolar inflammation, improve lung endothelial barrier permeability and modulate oxidative stress in vivo and in vitro. Recently, MSCs have been found to release small extracellular vesicles (sEVs) that can deliver functionally active biomolecules into recipient cells. The authors’ study was designed to determine whether sEVs released by MSCs would be effective in sepsis-induced ALI mice and to identify the potential mechanisms. Methods A total of 6 h after cercal ligation and puncture, the mice received saline, sEV-depleted conditioned medium (sEVD-CM) or MSC sEVs via the tail vein. Results The administration of MSC sEVs improved pulmonary microvascular permeability and inhibited both histopathological changes and the infiltration of polymorphonuclear neutrophils into lung tissues. In addition, the activities of antioxidant enzymes were significantly increased in the group treated with sEVs compared with the saline and sEVD-CM groups, whereas lipid peroxidation was significantly decreased. Furthermore, sEVs were found to possibly inhibit phosphorylation of the mitogen-activated protein kinase/nuclear factor kappa B (MAPK/NF-κB) pathway and degradation of IκB but increase the activities of nuclear factor erythroid 2-related factor 2 and heme oxygenase 1. Conclusions These findings suggest that one of the effective therapeutic mechanisms of sEVs against sepsis-induced ALI may be associated with upregulation of anti-oxidative enzymes and inhibition of MAPK/NF-κB activation.
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2021
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Human urine-derived stem cell-derived exosomal miR-21-5p promotes neurogenesis to attenuate Rett syndrome via the EPha4/TEK axis
Rett syndrome (RTT) is a rare neurodevelopmental disorder that results in multiple disabilities. Exosomal microRNA (miRs) from urine-derived stem cells (USCs) have been shown to induce neurogenesis and aid in functional recovery from brain ischemia. In the present study, we sought to determine whether that exosomal miR-21-5p from USCs could promote early neural formation in a model of RTT. USCs were isolated and evaluated by flow cytometry. Exosomes were analyzed by transmission electron microscopy, tunable resistive pulse sensing (TRPS), and western blotting. PKH26 fluorescent dyes were used to observe intake of exosomes in vivo and in vitro. An RTT mouse model was treated with exosomes for behavioral studies. Dual‐luciferase report gene assays were conducted to evaluate the relationship between miR-21-5p and Eph receptor A4 (EphA4). In vitro, treatment with exosomes from human urine‐derived stem cells (USC-Exos) increased the percentage of neuron-specific class III beta-tubulin (Tuj1)+ nerve cells as well as the transcription levels of β-III tubulin and doublecortin (DCX). A higher level of miR-21-5p was observed in USC-Exos, which promoted differentiation in NSCs by targeting the EPha4/TEK axis. In vivo, exosomal miR-21-5p improved the behavior, motor coordination, and cognitive ability of mice, facilitated the differentiation of NSCs in the subventricular zone of the lateral ventricle and promoted a marked rise in the number of DCX+ cells. Our data provide evidence that exosomal miR-21-5p from human USCs facilitate early nerve formation by regulating the EPha4/TEK axis.
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2021
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Hypoxic Conditions Promote the Angiogenic Potential of Human Induced Pluripotent Stem Cell-Derived Extracellular Vesicles
Stem cells secrete paracrine factors including extracellular vesicles (EVs) which can mediate cellular communication and support the regeneration of injured tissues. Reduced oxygen (hypoxia) as a key regulator in development and regeneration may influence cellular communication via EVs. We asked whether hypoxic conditioning during human induced pluripotent stem cell (iPSC) culture effects their EV quantity, quality or EV-based angiogenic potential. We produced iPSC-EVs from large-scale culture-conditioned media at 1%, 5% and 18% air oxygen using tangential flow filtration (TFF), with or without subsequent concentration by ultracentrifugation (TUCF). EVs were quantified by tunable resistive pulse sensing (TRPS), characterized according to MISEV2018 guidelines, and analyzed for angiogenic potential. We observed superior EV recovery by TFF compared to TUCF. We confirmed hypoxia efficacy by HIF-1α stabilization and pimonidazole hypoxyprobe. EV quantity did not differ significantly at different oxygen conditions. Significantly elevated angiogenic potential was observed for iPSC-EVs derived from 1% oxygen culture by TFF or TUCF as compared to EVs obtained at higher oxygen or the corresponding EV-depleted soluble factor fractions. Data thus demonstrate that cell-culture oxygen conditions and mode of EV preparation affect iPSC-EV function. We conclude that selecting appropriate protocols will further improve production of particularly potent iPSC-EV-based therapeutics.
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2021
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Immunoaffinity-Based Isolation of Melanoma Cell-Derived and T Cell-Derived Exosomes from Plasma of Melanoma Patients
Tumor-derived exosomes (TEX), a subset of small extracellular vesicles (EVs) which originate from the endocytic compartment of tumor cells, are emerging as key players in cancer progression. TEX circulate freely in patients’ body fluids and transfer bioactive cargos from tumor to various recipient cells. The molecular cargo of melanoma cell-derived exosomes (MTEX) mimics that of the tumor, and MTEX serve as a liquid biopsy that provides potentially useful information for cancer diagnosis, prognosis, or responses to therapy. Plasma of melanoma patients contains a mix of MTEX and exosomes produced by nonmalignant cells (NMTEX). Isolation of these exosome subtypes from the bulk of plasma exosomes is necessary to evaluate contributions of each as potential biomarkers of melanoma progression and outcome. Here, methods for separation of MTEX from T cell-derived exosomes from a single small volume of plasma and their subsequent molecular and functional characterization are described. Following size exclusion chromatography (SEC) to isolate total plasma exosomes, immune affinity-based capture of MTEX with anti-CSPG4 antibody and then of exosomes produced by T cells with anti-CD3 antibody is used to sequentially isolate the two subsets. This immune capture method enables the recovery of MTEX and CD3+ exosomes in quantities sufficient both for molecular profiling by flow cytometry or western blotting and for functional analyses.
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2021
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Implications of SP-C Oligomerization in Membrane Fragmentation and Pulmonary Surfactant Homeostasis
Pulmonary surfactant (PS) is a lipid-protein complex located at the airliquid interface over the alveolar epithelium, which is fundamental for breathing dynamics. Besides, PS has a key function in lung defence against inhaled pathogens and harmful particles, especially through the interaction with alveolar macrophages (AMs). Pulmonary surfactant protein C (SP-C) is essential for the biophysical functions of PS, although it has also been associated to lung defence due to its interaction with bacterial lipopolysaccharide (LPS) and with CD14, the macrophage LPS co-receptor. It has been proposed that the potential generation of SP-C oligomers as a consequence of the interaction of putative N- and C-termini oligomerization motifs within the protein could induce a curvature in PS membranes eventually causing their fragmentation. The resulting vesicles could be captured by alveolar type II epithelial cells (AT2) and/or AMs.The present work aimed to define the contribution of the suggested oligomerization motifs to protein-protein interaction and its effect in the homeostasis of the alveolar system. Our results from bimolecular fluorescence complementation assays shows that SP-C molecules can interact with each other. Using tunable resistive pulse sensing set-ups, we have determined that SP-C triggers membrane fragmentation provided that a proportion of 7.5% SP-C (P/L by mass) is reached in vesicles whose lipid composition mimics PS membranes. Finally, the fluorescence from the uptake of fluorochrome-labelled vesicles loaded with different concentrations of SP-C was evaluated in AMs and AT2 by flow cytometry. Our results suggest that SP-C promotes vesicle uptake in both cell lines, although the endocytotic profile was different in each cell type.
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2021
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In vitro validation of tumor-derived large extracellular vesicles isolation and characterization as suitable tool for liquid biopsy
Extracellular vesicles (EVs) are involved in intercellular communication mediated by nucleic acid and protein exchange. Their role in cancer has been widely demonstrated and EVs are under investigation as possible tools for liquid biopsy. Large (L)-EVs represent a heterogeneous class of EVs that are characterized by a diameter >200 nm. Those derived by cancer cells show peculiar cargos including oncogenic proteins, lipids and large DNA fragments. Aim of this study was to validate in vitro the isolation, characterization and mutational analysis of tumor-derived L-EVs. L-EVs were isolated from supernatants (50 ml) of either prostate cancer (PC3) and melanoma (SK-Mel28) cell cultures by centrifugation at 10,000x g, and then resuspended in 200 µl of PBS. Tunable resistive pulse sensing (qNANO) investigated both dimensions and concentration of L-EV preparations. Flow cytometry and Western blotting were used to analyze the expression of typical markers of EVs (CD63 and CD81 tetraspanins) and L-EVs (HSPA5 or CK18), as well as of ALIX (cytoplasmic protein) and APOA1 (contaminant) as internal controls. For genomic analysis, L-EVs were initially treated with DNAse I, Exonuclease III and RNAse to disrupt the external nucleic acid coating, then L-EV-DNA was extracted by DNeasy blood and tissue Kit (Qiagen). Quantitative and qualitative analyses of L-EV-DNA have been assessed with Bioanalyzer DNA High Sensitivity Chip Kit (Agilent) and 1% agarose gel electrophoresis, as compared to parental cell DNA. Finally, Sanger sequencing was used to identify TP53 (p.K139fs*31) or BRAF (p.V600E) mutations in L-EV-DNA, respectively form PC3 and SK-Mel28 cells. L-EVs were purified at a mean concentration of 16.4±5.1 x 103 vesicles/µl. Typical characteristics of L-EVs were confirmed, including a diameter ranging from 0.5 µm to 2 µm as well as the expression of CD63/CD81 tetraspanins and HSPA5 or CK18. Moreover, L-EV preparations resulted all negative for APOA1 but positive for ALIX expression, confirming sample purity and vesicle integrity. The DNA content from each sample of L-EVs ranged from 0.36 to 5.21 ng/µl. Qualitative analysis revealed long DNA fragments (range 3,000-10,000 bp) packaged in L-EVs in a fashion almost similar to the genomic DNA from parental cells. Finally, DNA sequencing revealed either the BRAF p.V600E or the TP53 p.K139fs*31 mutations - respectively from SK-Mel28 and PC3 cells - in both L-EV-DNA and genomic DNA. L-EVs are easily obtainable from culture supernatants and represent a biological surrogate of the cell producer. L-EVs contain large DNA fragments that are suitable for molecular testing, including the identification of pathogenic gene variants. These results make L-EVs ideal candidates as liquid biopsy in oncology, thus justifying further efforts to validate their isolation from body fluids and down-stream analysis. Citation Format: Gaetano Pezzicoli, Domenica Lovero, Marco Tucci, Camillo Porta, Francesco Mannavola. In vitro validation of tumor-derived large extracellular vesicles isolation and characterization as suitable tool for liquid biopsy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2012.
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2021
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In vivo silencing of amphiregulin by a novel effective Self-Assembled-Micelle inhibitory RNA ameliorates renal fibrosis via inhibition of EGFR signals
Amphiregulin (AREG) is a transmembrane glycoprotein recently implicated in kidney fibrosis. Previously, we reported that the AREG-targeting Self-Assembled-Micelle inhibitory RNA (SAMiRNA-AREG) alleviated fibrosis by stably silencing the AREG gene, and reduced the side effects of conventional siRNA treatment of pulmonary fibrosis. However, the therapeutic effect of SAMiRNA-AREG in renal fibrosis has not been studied until now. We used two animal models of renal fibrosis generated by a unilateral ureteral obstruction (UUO) and an adenine diet (AD) to investigate whether SAMiRNA-AREG inhibited renal fibrosis. To investigate the delivery of SAMiRNA-AREG to the kidney, Cy5-labeled SAMiRNA-AREG was injected into UUO- and AD-induced renal fibrosis models. In both kidney disease models, SAMiRNA-AREG was delivered primarily to the damaged kidney. We also confirmed the protective effect of SAMiRNA-AREG in renal fibrosis models. SAMiRNA-AREG markedly decreased the UUO- and AD-induced AREG mRNA expression. Furthermore, the mRNA expression of fibrosis markers, including α-smooth muscle actin, fibronectin, α1(I) collagen, and α1(III) collagen in the UUO and AD-induced kidneys, was diminished in the SAMiRNA-AREG-treated mice. The transcription of inflammatory markers (tumor necrosis factor-α and monocyte chemoattractant protein-1) and adhesion markers (vascular cell adhesion molecule 1 and intercellular adhesion molecule 1) was attenuated. The hematoxylin and eosin, Masson’s trichrome, and immunohistochemical staining results showed that SAMiRNA-AREG decreased renal fibrosis, AREG expression, and epidermal growth factor receptor (EGFR) phosphorylation in the UUO- and AD-induced models. Moreover, we studied the effects of SAMiRNA-AREG in response to TGF-β1 in mouse and human proximal tubule cells, and mouse fibroblasts. TGF-β1-induced extracellular matrix production and myofibroblast differentiation were attenuated by SAMiRNA-AREG. Finally, we confirmed that upregulated AREG in the UUO or AD models was mainly localized in the distal tubules. In conclusion, SAMiRNA-AREG represents a novel siRNA therapeutic for renal fibrosis by suppressing EGFR signals.
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2021
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A magnetic bead-mediated selective adsorption strategy for extracellular vesicle separation and purification
Extracellular vesicles (EVs) are membrane-encapsulated particles with critical biomedical functions, including mediating intercellular communication, assisting tumor metastasis, and carrying protein and microRNA biomarkers. The downstream applications of EVs are greatly influenced by the quality of the isolated EVs. However, almost none of the separation methods can simultaneously achieve both high yield and high purity of the isolated EVs, thus making the isolation of EVs an essential challenge in EV research. Here, we developed a magnetic bead-mediated selective adsorption strategy (MagExo) for easy-to-operate EV isolation. Benefited from the presence of an adsorption window between EVs and proteins under the effect of a hydrophilic polymer, EVs tend to adsorb on the surface of magnetic beads selectively and can be separated from biological fluids with high purity by simple magnetic separation. The proposed method was used for EV isolation from plasma and cell culture media (CCM), with two times higher yield and comparable purity of the harvested EVs to that obtained by ultracentrifugation (UC). Downstream applications in proteomics analysis showed 86.6% (plasma) and 86.5% (CCM) of the analyzed proteins were matched with the ExoCarta database, which indicates MagExo indeed enriches EVs efficiently. Furthermore, we found the target RNA amount of the isolated EVs by MagExo were almost dozens and hundred times higher than the gold standard DG-UC and ultracentrifugation (UC) methods, respectively. All the results show that MagExo is a reliable, easy, and efficient approach to harvest EVs for a wide variety of downstream applications with minimized sample usage. Statement of Significance Extracellular vesicles (EVs) are presently attracting increasing interest among clinical and scientific researchers. Although the downstream applications of EVs are recognized to be greatly affected by the quality of the isolated EVs, almost none of the separation methods can simultaneously achieve high yield and high purity of the isolated EVs; this makes the isolation of EVs an essential challenge in EV research. In the present work, we proposed a simple and easy-to-operate method (MagExo) for the separation and purification of EVs based on the phenomenon that EVs can be selectively adsorbed on the surface of magnetic microspheres in the presence of a hydrophilic polymer. The performance of MagExo was comparable to or even better than that of gold standard methods and commercial kits, with two times higher yield and comparable purity of the harvested EVs to that achieved with ultracentrifugation (UC); this could meet the requirements of various EV-associated downstream applications. In addition, MagExo can be easily automated by commercial liquid workstations, thus significantly improving the isolation throughput and paving a new way in clinical diagnosis and treatment.
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2021
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A novel protein signature from plasma extracellular vesicles for non-invasive differential diagnosis of idiopathic pulmonary fibrosis
Background Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia of unknown etiology often leading to respiratory failure. Over half of IPF patients present with discordant features of usual interstitial pneumonia on high-resolution computed tomography at diagnosis which warrants surgical lung biopsy to exclude the possibility of other interstitial lung diseases (ILDs). Therefore, there is a need for non-invasive biomarkers for expediting the differential diagnosis of IPF. Methods Using mass spectrometry, we performed proteomic analysis of plasma extracellular vesicles (EVs) in a cohort of subjects with IPF, chronic hypersensitivity pneumonitis, nonspecific interstitial pneumonitis, and healthy subjects (HS). A five-protein signature was identified by lasso regression and was validated in an independent cohort using ELISA. We evaluated the concordance between plasma EV proteome and the lung transcriptome data. Lastly, we compared the molecular pathways overrepresented in IPF by differentially expressed proteins and transcripts from EVs and lung tissues, respectively. Results The five-protein signature derived from mass spectrometry data showed area under the receiver operating characteristic curve of 0.915 (95%CI: 0.819-1.011) and 0.958 (95%CI: 0.882-1.034) for differentiating IPF from other ILDs and from HS, respectively. We also found that the EV protein expression profiles mirrored their corresponding mRNA expressions in IPF lungs. Further, we observed an overlap in the EV proteome- and lung mRNA-associated molecular pathways. Conclusions We discovered a plasma EV-based protein signature for differential diagnosis of IPF and validated this signature in an independent cohort. The signature needs to be tested in large prospective cohorts to establish its clinical utility. Competing Interest Statement AKP is employed with Izon Science US Ltd. The company has no role in design of the study and acquisition of experimental data and interpretation. All other authors have no conflict of interests. Funding Statement This work was supported by UT System Rising STARs award and core funds from UTHSCT, Tyler, Texas, to NVK. DN received funding from NIH (R01 GM083122). Cryo-TEM is supported by Cancer Prevention and Research Institute of Texas grant RR140082 to DN. Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study was approved by institutional review boards of University of Pittsburgh (IRB STUDY19040326 and STUDY20030223), Brigham and Womens hospital (IRB2012P000840), Hiroshima University (IRBM326) and University of Texas Health Science Center at Tyler (IRB 20-019 & 0000370). All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes
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2021
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An SPRi-based biosensor pilot study: Analysis of multiple circulating extracellular vesicles and hippocampal volume in Alzheimer's disease
One of the main hurdles in the study of Alzheimer’s Disease (AD) is the lack of easily accessible and sensitive biomarkers for the diagnosis, the prediction of the disease progression rate and the evaluation of rehabilitative and pharmacological treatments. Extracellular Vesicles (EVs) are nanoscale particles released by body cells, studied as promising biomarkers of AD as they are involved in the onset and progression of the disease. In the strive for a reliable and sensitive method to analyze EVs, we applied our recently developed biosensor based on Surface Plasmon Resonance imaging (SPRi) technology for the identification and profiling of neural EVs populations circulating in the plasma of 10 AD patients and 10 healthy subjects. The SPRi-array was designed to separate simultaneously EVs released by neurons, astrocytes, microglia and oligodendrocytes, and to evaluate the presence and the relative amount of specific surface molecules related to pathological processes including translocator protein (TSPO), β-Amyloid and ganglioside M1. As results, significant variations in the relative amount and cargoes of specific brain-derived populations of EVs were observed comparing EVs coming from AD patients and healthy subjects, finding the main differences in the activation phenotype of microglia EVs, in the lipid moieties on generic EVs and in the β-Amyloid expression on surfaces of neuronal EVs. Besides, the demonstrated correlation of SPRi data with Magnetic Resonance Imaging analysis, provided support for using the SPRi-based biosensor for the evaluation of neurodegeneration detecting and characterizing circulating EVs as peripheral biomarkers for the diagnosis and monitoring of progression and rehabilitation treatments in AD patients.
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2021
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Antioxidative Effects of Carrot-Derived Nanovesicles in Cardiomyoblast and Neuroblastoma Cells
Oxidative stress is implicated in many diseases, including cardiovascular and neurodegenerative diseases. Because an increased level of oxidative stress causes apoptosis, it is necessary to inhibit cellular responses to oxidative stress. In this study, Carex, a nanovesicle from carrot, was isolated and investigated as a novel biomaterial with antioxidative function in cardiomyoblasts and neuroblastoma cells. A high concentration of nanovesicles was purified from carrots, using size-exclusion chromatography in combination with ultrafiltration. The characterization of Carex demonstrated that it had properties similar to those of extracellular vesicles. Carex showed low cytotoxicity in both H9C2 cardiomyoblasts and SH-SY5Y neuroblastoma cells, when a high level of Carex was delivered to the cells. Carex was further investigated for its antioxidative and apoptotic effects, and it significantly inhibited ROS generation and apoptosis in vitro in myocardial infarction and Parkinson’s disease models. Carex inhibited the reduction of antioxidative molecule expression, including Nrf-2, HO-1, and NQO-1, in both models. Considering its antioxidative function and high production yield, Carex is a potential drug candidate for the treatment of myocardial infarction as well as Parkinson’s disease. Thus, the results demonstrated in this study will contribute to an exploration of a novel drug, using nanovesicles from plants, including carrots.
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2021
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Assembly and Entry of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2): Evaluation Using Virus-Like Particles
Research on infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is currently restricted to BSL-3 laboratories. SARS-CoV2 virus-like particles (VLPs) offer a BSL-1, replication-incompetent system that can be used to evaluate virus assembly and virus-cell entry processes in tractable cell culture conditions. Here, we describe a SARS-CoV2 VLP system that utilizes nanoluciferase (Nluc) fragment complementation to track assembly and entry. We utilized the system in two ways. Firstly, we investigated the requirements for VLP assembly. VLPs were produced by concomitant synthesis of three viral membrane proteins, spike (S), envelope (E), and matrix (M), along with the cytoplasmic nucleocapsid (N). We discovered that VLP production and secretion were highly dependent on N proteins. N proteins from related betacoronaviruses variably substituted for the homologous SARS-CoV2 N, and chimeric betacoronavirus N proteins effectively supported VLP production if they contained SARS-CoV2 N carboxy-terminal domains (CTD). This established the CTDs as critical features of virus particle assembly. Secondly, we utilized the system by investigating virus-cell entry. VLPs were produced with Nluc peptide fragments appended to E, M, or N proteins, with each subsequently inoculated into target cells expressing complementary Nluc fragments. Complementation into functional Nluc was used to assess virus-cell entry. We discovered that each of the VLPs were effective at monitoring virus-cell entry, to various extents, in ways that depended on host cell susceptibility factors. Overall, we have developed and utilized a VLP system that has proven useful in identifying SARS-CoV2 assembly and entry features.
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2021
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Bioinspired artificial exosomes based on lipid nanoparticles carrying let-7b-5p promote angiogenesis in vitro and in vivo
MicroRNAs (miRNAs) regulate gene expression by post-transcriptional inhibition of target genes. Proangiogenic small extracellular vesicles (sEVs; popularly identified with the name “exosomes”) with a composite cargo of miRNAs are secreted by cultured stem cells and present in human biological fluids. Lipid nanoparticles (LNPs) represent an advanced platform for clinically approved delivery of RNA therapeutics. In this study, we aimed to (1) identify the miRNAs responsible for sEV-induced angiogenesis; (2) develop the prototype of bioinspired “artificial exosomes” (AEs) combining LNPs with a proangiogenic miRNA, and (3) validate the angiogenic potential of the bioinspired AEs. We previously reported that human sEVs from bone marrow (BM)-CD34+ cells and pericardial fluid (PF) are proangiogenic. Here, we have shown that sEVs secreted from saphenous vein pericytes and BM mesenchymal stem cells also promote angiogenesis. Analysis of miRNA datasets available in-house or datamined from GEO identified the let-7 family as common miRNA signature of the proangiogenic sEVs. LNPs with either hsa-let-7b-5p or cyanine 5 (Cy5)-conjugated Caenorhabditis elegans miR-39 (Cy5-cel-miR-39; control miRNA) were prepared using microfluidic micromixing. let-7b-5p-AEs did not cause toxicity and transferred functionally active let-7b-5p to recipient endothelial cells (ECs). let-7b-AEs also improved EC survival under hypoxia and angiogenesis in vitro and in vivo. Bioinspired proangiogenic AEs could be further developed into innovative nanomedicine products targeting ischemic diseases.
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2021
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Cancer-Associated Fibroblasts Exosomal miR-106a Promotes Breast Cancer Invasion and Metastasis by Down-regulation of TCEAL7
Studies have shown that cancer-associated broblasts (CAFs) play an irreplaceable role in the occurrence and development of tumors. Therefore, exploring the action and mechanism of CAFs on tumor cells is particularly important for designing new and effective treatments and improving prognosis of tumors. For exosomes have been shown to play vital roles in intercellular communication, in this study, we compared the effects of CAFs-derived exosomes and NFs-derived exosomes on breast cancer cell proliferation, migration, and metastasis. The results showed that exosomes from both CAFs and NFs could enter into breast cancer cells and CAFs-derived exosomes had a more enhancing effect on breast cancer cell proliferation and invasion than NFs-derived exosomes. Furthermore, it was found that the expression levels of miR-106a in exosomes derived from CAFs were signicantly up-regulated than that of NFsderived exosomes and what’s more, in vitro and in vivo studies have shown that miR-106a can promote breast cancer cell proliferation, migration and metastasis by specically binding to the 3'UTR of TCEAL7. It is inspiring to nd that the miR-106a-TCEAL7 pathway promotes Snail nuclear ectopic activation by activating NF-κB, thereby inducing epithelial-mesenchymal transition and promoting cell proliferation and metastasis. Moreover, a mouse xenograft model conrmed that CAFs-derived exosomes miR-106a could promote tumor metastasis. The above data shows that CAFs-derived exosomes miR-106a promote Snail nuclear ectopic by targeting TCEAL7 to activate the NF-κB pathway, thereby inducing EMT, invasion and metastasis of breast cancer. Targeting CAFs-derived exosome miR-106a may be a potential treatment option to overcome breast cancer progression.
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2021
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Characterization of extracellular vesicles and synthetic nanoparticles with four orthogonal single‐particle analysis platforms
We compared four orthogonal technologies for sizing, counting, and phenotyping of extracellular vesicles (EVs) and synthetic particles. The platforms were: single-particle interferometric reflectance imaging sensing (SP-IRIS) with fluorescence, nanoparticle tracking analysis (NTA) with fluorescence, microfluidic resistive pulse sensing (MRPS), and nanoflow cytometry measurement (NFCM). EVs from the human T lymphocyte line H9 (high CD81, low CD63) and the promonocytic line U937 (low CD81, high CD63) were separated from culture conditioned medium (CCM) by differential ultracentrifugation (dUC) or a combination of ultrafiltration (UF) and size exclusion chromatography (SEC) and characterized by transmission electron microscopy (TEM) and Western blot (WB). Mixtures of synthetic particles (silica and polystyrene spheres) with known sizes and/or concentrations were also tested. MRPS and NFCM returned similar particle counts, while NTA detected counts approximately one order of magnitude lower for EVs, but not for synthetic particles. SP-IRIS events could not be used to estimate particle concentrations. For sizing, SP-IRIS, MRPS, and NFCM returned similar size profiles, with smaller sizes predominating (per power law distribution), but with sensitivity typically dropping off below diameters of 60 nm. NTA detected a population of particles with a mode diameter greater than 100 nm. Additionally, SP-IRIS, MRPS, and NFCM were able to identify at least three of four distinct size populations in a mixture of silica or polystyrene nanoparticles. Finally, for tetraspanin phenotyping, the SP-IRIS platform in fluorescence mode was able to detect at least two markers on the same particle, while NFCM detected either CD81 or CD63. Based on the results of this study, we can draw conclusions about existing single-particle analysis capabilities that may be useful for EV biomarker development and mechanistic studies.
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2021
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Characterization of feces-derived bacterial membrane vesicles and the impact of their origin on the inflammatory response
The human gastrointestinal tract harbors a diverse and complex microbiome, which interacts in a variety of ways with the host. There is compelling evidence that gut microbial dysbiosis, defined as an alteration of diversity and abundance in intestinal microbes, is an etiological factor in inflammatory bowel disease (IBD). Membrane vesicles (MVs), which are nano-sized particles released by bacteria, have been found to interact with the host and modulate the development and function of the immune system. As a result MVs have been suggested to play a critical role in both health and disease. In this study we developed a method to isolate, characterize and assess the immunoreactivity of heterogeneous populations of MVs from fecal samples (fMVs) of healthy volunteers. We successfully isolated 2*109-2*1010 particles/ml from 0.5 gram of feces by using a combination of ultrafiltration and size exclusion chromatography (SEC) from 10 fecal samples. Bead-based flowcytometry in combination with tunable resistive pulse sensing (TRPS) provided a reliable method for (semi-)quantitative determination of fMVs originating from both Gram-positive and Gram-negative bacteria, while transmission electron microscopy confirmed the presence of fMVs. Real time 16s PCR on bacterial cell fractions or isolated fMVs DNA of the most common phyla (Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria) revealed differences in the relative abundance between bacteria and the fMVs. Moreover, fMVs evoke the release of TNF- by THP-1 cells in a dose-dependent matter. Also, a significant positive correlation was found between Actinobacteria/-Proteobacteria derived vesicles and the release of TNF-. It has become increasingly clear that fMVs could provide an additional layer to the definition of homeostasis or dysbiosis of the microbiota. The current study supports their potential involvement in the intestinal homeostasis or inflammatory disorders and provides putative interesting incentives for future research.
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2021
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Circulating Extracellular Vesicle Cargo as Bioinformants of 'at-risk'Carotid Artery Stenosis
Objectives Carotid artery atherosclerosis is a major cause of ischemic stroke. Managing patients with asymptomatic disease remains challenging, given the lack of reliable tests to identify the subgroup of patients prone to plaque progression and stroke. Given the functional and diagnostic roles of extracellular vesicle (EV) contents, we hypothesized that plasma EV-derived microRNA (miRNA) differs between symptomatic and asymptomatic patients. Methods EVs were isolated via serial centrifugation followed by enrichment using size exclusion chromatography (SEC) (qEVoriginal columns 70 nm; Izon Science Ltd). EV isolation was confirmed according to MISEV 2018 guidelines: Western blot analysis of common EV markers (CD63, CD81, Alix), nanoparticle tracking analysis (NTA), and cryogenic transmission electron microscopy (Cryo-TEM). Lipoprotein contamination was assessed via enzyme-linked immunosorbent assay of individual SEC fractions (R&D Systems; DAPA10, DAPB00). Next-generation sequencing was performed on EVs (HTG Molecular Diagnostics, Inc.), and differential miRNA expression evaluated using Partek Genomics Suite software (version 8.0). Results Twelve patient plasma samples were collected (n = 6 symptomatic; n = 6 asymptomatic). The average age of the cohort was 70.0 ± 5.7 years (asymptomatic, 67.0 ± 5.5 vs symptomatic, 72.5 ± 5.5 years). All patients had severe stenoses with similar peak systolic velocity (asymptomatic 403.2 ± 84.43 vs symptomatic 371.6 ± 175.25; P = .50) and internal carotid artery (ICA):common carotid artery (CCA) ratios (asymptomatic, 5.36 ± 1.07 vs symptomatic, 7.3 ± 5.00; P = .50). CD63 expression confirmed EV enrichment in fractions 7 to 10, with minimal lipoprotein contamination. EV isolation was further confirmed by CD81 and Alix expression (n = 3 patient samples per group). Cryo-TEM identified EVs as bi-layered nanoparticles with electron dense cores (Fig 1). NTA revealed no significant differences in EV concentration or size between groups (n = 3; P > .05). Principal component and heatmap analysis of miRNA sequencing data revealed symptomatic carotid plasma samples clustered together, whereas asymptomatic samples were either starkly different (n = 5) or approximated the symptomatic profiles (n = 1), suggesting a disease gradient (Fig 2). When symptomatic carotid plasma EV-miRNA profiles were compared with asymptomatic specimens, 190 miRNAs were differentially expressed, with miRNA-654-5p and miRNA-127-3p being the most upregulated, and downregulated, respectively (P < .05, fold-change −2< or >2, excluding miRNA with counts <100). Gene set enrichment identified regulation of protein metabolic processes, and negative regulation of cell communication, signaling, and signal transduction as predicted targets of differentially expressed EV-miRNA (P-value < .05). Conclusions Plasma EV-miRNA profiles may differentiate symptomatic vs asymptomatic carotid stenosis and, together with clinical characteristics, may be used in risk stratification of asymptomatic patients.
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2021
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Circulating extracellular vesicles from patients with acute chest syndrome disrupt adherens junctions between endothelial cells
Background Small cell-derived extracellular vesicles (EVs) can affect endothelial function. We previously found that patients with sickle cell disease (SCD) have greater numbers of circulating EVs than subjects without the disease, and the EVs differentially disrupt endothelial integrity in vitro. Because endothelial disruption is a critical component of acute chest syndrome (ACS), we hypothesized that EVs isolated during ACS would induce greater endothelial damage than those isolated at baseline. Methods Nine pediatric subjects had plasma isolated at baseline and during ACS from which EVs were isolated. Cultured microvascular endothelial cells were treated with EVs and then studied by immunofluorescence microscopy to localize VE-cadherin and F-actin. Results The EVs had a diameter of 95 nm. They contained CD63 and flotillin-1, which were increased in SCD patients (5–13-fold compared to control) and further increased between baseline and ACS (24–57%). The EVs contained hemoglobin, glycophorin A, and ferritin. Treatment with baseline EVs caused modest separation of endothelial cells, while ACS EVs caused substantial disruptions of the endothelial cell monolayers. EVs from subjects with ACS also caused a 50% decrease in protein levels of VE-cadherin. Conclusions These results suggest that circulating EVs can modulate endothelial integrity contributing to the development of ACS in SCD patients by altering cadherin-containing intercellular junctions. Impact - Sickle cell disease patients have circulating extracellular vesicles (EVs) that modulate endothelial integrity by altering cadherin-containing intercellular junctions. - - Disruption is more severe by EVs obtained during acute chest syndrome (ACS). - - These results expand our knowledge of the pathophysiology of acute chest syndrome and the vasculopathies of sickle cell disease.
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2021
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Comparative proteome profiling in exosomes derived from porcine colostrum versus mature milk reveals distinct functional proteomes
Exosomes are membranous vesicles of endocytic origin, recently been considered as major players in cell-cell communication. Milk is highly complex, and diverse biocomponents provide adequate nutrition, transfer immunity, and promote adequate neonate development. Milk exosomes are suggested to have a key role in these processes, yet to be further explored, and the alteration of the exosomes' cargo in different stages of lactation stages is important for understanding the factors relevant in nursing and also for improving milk replacer products both for humans and animals. We isolated exosomes from porcine milk in different lactation stages and analyzed their content using a TMT-based high-resolution quantitative proteomic approach. Exosomes were isolated using ultracentrifugation coupled with size exclusion chromatography to enrich milk-derived exosomes in samples obtained at day 0, 7, and 14 after parturition, and characterized by nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. Quantitative proteomics analysis revealed different proteome profiles for colostrum exosomes and milk exosomes. The functional analysis highlighted pathways related to the regulation of homeostasis to be upregulated in colostrum exosomes, and pathways such as endothelial cell development and lipid metabolism to be upregulated in mature milk exosomes. This study endorses the importance of exosomes as active biocomponents of milk and provides knowledge for future studies exploring their role in the regulation of immunity and growth of the newborn.
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2021
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Comparative study of commercial protocols for high recovery of high-purity mesenchymal stem cell-derived extracellular vesicle isolation and their efficient labeling with fluorescent dyes
The extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can be used as carriers for therapeutic molecules and drugs to target disordered tissues. This aimed to compare the protocols used for isolation of MSC-derived EVs by comparing EV collection conditions and three commercial purification kits. We also determined appropriate fluorescent dyes for labeling EVs. MSC-derived EVs were efficiently secreted during cell growth and highly purified by the phosphatidyl serine-based affinity kit. Although the EV membrane was more efficiently labeled with the fluorescent dye PKH67 compared to other probes, the efficiency was not enough to accurately analyze the endothelial cellular uptake of EVs. Results verified the easy protocol for isolating and fluorescently labeling EVs with commercial reagents and kits, but meanwhile, further modification of the protocol is required in order to scale up the amount of EVs derived from MSCs using fluorescent probes. Graphical Abstract The extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can be used as carriers for therapeutic molecules and drugs. This aimed to compare the protocols used for isolation of EVs by comparing EV collection conditions and three commercial purification kits. MSC-derived EVs were efficiently secreted during cell growth and highly purified by the phosphatidyl serine-based affinity kit. Results verified the easy protocol for isolating and fluorescently labeling EVs with commercial reagents and kits, but meanwhile, further modification of the protocol is required in order to scale up the amount of EVs derived from MSCs using fluorescent probes.
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2021
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Comparison and optimization of nanoscale extracellular vesicle imaging by scanning electron microscopy for accurate size-based profiling and morphological analysis
Nanosized extracellular vesicles (EVs) have been found to play a key role in intercellular communication, offering opportunities for both disease diagnostics and therapeutics. However, lying below the diffraction limit and also being highly heterogeneous in their size, morphology and abundance, these vesicles pose significant challenges for physical characterization. Here, we present a direct visual approach for their accurate morphological and size-based profiling by using scanning electron microscopy (SEM). To achieve that, we methodically examined various process steps and developed a protocol to improve the throughput, conformity and image quality while preserving the shape of EVs. The study was performed with small EVs (sEVs) isolated from a non-small-cell lung cancer (NSCLC) cell line as well as from human serum, and the results were compared with those obtained from nanoparticle tracking analysis (NTA). While the comparison of the sEV size distributions showed good agreement between the two methods for large sEVs (diameter > 70 nm), the microscopy based approach showed a better capacity for analyses of smaller vesicles, with higher sEV counts compared to NTA. In addition, we demonstrated the possibility of identifying non-EV particles based on size and morphological features. The study also showed process steps that can generate artifacts bearing resemblance with sEVs. The results therefore present a simple way to use a widely available microscopy tool for accurate and high throughput physical characterization of EVs.
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2021
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Comparison of isolation methods using commercially available kits for obtaining extracellular vesicles from cow milk
Extracellular vesicles (EV) are important for delivering biologically active substances to facilitate cell-to-cell communication. Milk-derived EV are widely known because of their potential for immune enhancement. However, procedures for isolating milk-derived EV have not been fully established. To obtain pure milk-derived EV and accurately reveal their function, such procedures must be established. The aim of the present study was to compare methods using commercially available kits for isolating milk-derived EV. Initially, we investigated procedures to remove casein, which is the major obstacle in determining milk-derived EV purity. We separated whey using centrifugation only, acetic acid precipitation, and EDTA precipitation. Then, we isolated milk-derived EV by ultracentrifugation, membrane affinity column, size exclusion chromatography (SEC), polymer-based isolation, or phosphatidylserine-affinity isolation. Using EV count per milligram of protein, which is a good indicator of purity, we determined that acetic acid precipitation was the best method for removing casein. Using nanoparticle tracking analysis, protein quantity analysis, and RNA quantity analysis, we comprehensively compared each isolation method for its purity and yield. We found that SEC-based qEV column (Izon Science) could collect purer milk-derived EV at higher quantities. Thus, a combination of acetic acid precipitation and qEV can effectively isolate high amounts of pure extracellular vesicles from bovine milk.
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2021
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Comprehensive analysis and comparison of proteins in salivary exosomes of climacteric and adolescent females
Currently, it is difficult to extract exosomes with stable physicochemical properties from saliva. Furthermore, due to inadequate availability of basic data, the application of salivary exosomes as a diagnostic material is limited. In this study, we aimed to investigate an easier method for extraction of exosomes from whole saliva and compared proteins in salivary exosomes derived from subjects of two age groups. Salivary exosomes were extracted from nine females (56.7 ± 1.17 years old; climacteric or 19.9 ± 0.20 years old; adolescent) using commercial reagents and kits and detected using western blotting with anti-exosome marker antibodies. Exosome particle size and exosome-containing proteins were identified using NanoSight® and liquid chromatography with tandem mass spectrometry, respectively. In addition, an efficient method of exosome extraction from saliva using a reagent and without the use of an ultracentrifuge was shown. Our results showed a higher total protein content and larger particle size in climacteric exosomes than in adolescent exosomes. However, adolescent exosomes showed a larger variety of proteins (780 proteins) than the climacteric exosomes (573 proteins). Altogether, 893 proteins were identified in the salivary exosomes. Although viral process-, ribosome- and structural molecule-related proteins were higher in the adolescent exosomes, the levels of major salivary proteins such as immunoglobulins and amylase, were higher in the climacteric exosomes than in the adolescent exosomes. The data presented, which show the fundamental protein composition of salivary exosomes and the changes that occur with age, are beneficial in both diagnostic and biotechnological applications.
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2021
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Defining candidate mRNA and protein EV biomarkers to discriminate ccRCC and pRCC from non-malignant renal cells in vitro
Renal cell carcinoma (RCC) accounts for over 400,000 new cases and 175,000 deaths annually. Diagnostic RCC biomarkers may prevent overtreatment in patients with early disease. Extracellular vesicles (EVs) are a promising source of RCC biomarkers because EVs carry proteins and messenger RNA (mRNA) among other biomolecules. We aimed to identify biomarkers and assess biological functions of EV cargo from clear cell RCC (ccRCC), papillary RCC (pRCC), and benign kidney cell lines. EVs were enriched from conditioned cell media by size exclusion chromatography. The EV proteome was assessed using Tandem Mass Tag mass spectrometry (TMT-MS) and NanoString nCounter technology was used to profile 770 cancer-related mRNA present in EVs. The heterogeneity of protein and mRNA abundance and identification highlighted the heterogeneity of EV cargo, even between cell lines of a similar pathological group (e.g., ccRCC or pRCC). Overall, 1726 proteins were quantified across all EV samples, including 181 proteins that were detected in all samples. In the targeted profiling of mRNA by NanoString, 461 mRNAs were detected in EVs from at least one cell line, including 159 that were present in EVs from all cell lines. In addition to a shared EV cargo signature, pRCC, ccRCC, and/or benign renal cell lines also showed unique signatures. Using this multi-omics approach, we identified 34 protein candidate pRCC EV biomarkers and 20 protein and 8 mRNA candidate ccRCC EV biomarkers for clinical validation.
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2021
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Detection of Tumor-Associated Membrane Receptors on Extracellular Vesicles from Non-Small Cell Lung Cancer Patients via Immuno-PCR
Precision cancer medicine for non-small-cell lung cancer (NSCLC) has increased patient survival. Nevertheless, targeted agents towards tumor-associated membrane receptors only result in partial remission for a limited time, calling for approaches which allow longitudinal treatment monitoring. Rebiopsy of tumors in the lung is challenging, and metastatic lesions may have heterogeneous signaling. One way ahead is to use liquid biopsies such as circulating tumor DNA or small extracellular vesicles (sEVs) secreted by the tumor into blood or other body fluids. Herein, an immuno-PCR-based detection of the tumor-associated membrane receptors EGFR, HER2, and IGF-1R on CD9-positive sEVs from NSCLC cells and pleural effusion fluid (PE) of NSCLC patients is developed utilizing DNA conjugates of antibody mimetics and affibodies, as detection agents. Results on sEVs purified from culture media of NSCLC cells treated with anti-EGFR siRNA, showed that the reduction of EGFR expression can be detected via immuno-PCR. Protein profiling of sEVs from NSCLC patient PE samples revealed the capacity to monitor EGFR, HER2, and IGF-1R with the immuno-PCR method. We detected a significantly higher EGFR level in sEVs derived from a PE sample of a patient with an EGFR-driven NSCLC adenocarcinoma than in sEVs from PE samples of non-EGFR driven adenocarcinoma patients or in samples from patients with benign lung disease. In summary, we have developed a diagnostic method for sEVs in liquid biopsies of cancer patients which may be used for longitudinal treatment monitoring to detect emerging bypassing resistance mechanisms in a noninvasive way.
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2021
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Development of fast, reliable and automated isolation and fractionation methods for nanosized subpopulations of human biomacromolecules
This doctoral thesis describes the development of fast, reliable and automated isolation and fractionation methods for nanosized subpopulations of human biomacromolecules. The focus of the study was on subpopulations of lipoproteins and extracellular vesicles (EVs) that are important in the detection of different diseases, such as atherosclerotic cardiovascular diseases and cancer, and may even possess therapeutic potential. In the thesis, immunoaffinity chromatography (IAC) with selective antibodies immobilized on the monolithic disk columns were utilized for the selective isolation of biomacromolecules from human plasma, while asymmetrical flow field-flow fractionation (AsFlFFF or AF4) was able to fractionate relevant subpopulations of biomacromolecules (e.g., small dense low-density lipoproteins, exomeres, and exosomes) from the isolates. Continuous flow quartz crystal microbalance (QCM) and partial filling affinity capillary electrophoresis (PF-ACE) were employed to study the affinity of the interactions between the antibody and lipoproteins. The first step was to develop a method to study interactions between antibody and lipoproteins to select a high affinity antibody useful for the isolation of lipoprotein subpopulations by IAC. The interaction data obtained with PF-ACE was analyzed to determine the heterogeneity of the interactions with adsorption energy distribution calculations, while the QCM data was processed with interaction maps. The affinity constants obtained with QCM and PF-ACE agreed well with each other. Next, the IAC methods were developed to capture EVs of different cellular origins from human plasma using anti-CD9 monoclonal antibody (mAb), while anti-CD61 mAb was exploited to capture platelet-derived EVs. The anti-apolipoprotein B-100 (anti-apoB-100) mAb was exploited to immunocapture apoB-100 containing lipoproteins. The anti-apoB-100 mAb was also characterized by the PF-ACE and QCM studies. Appropriate elution conditions were found for the IAC methods, which has often been an issue with magnetic beads-based immunoaffinity methods. Since IAC allowed selective isolation of EVs and lipoproteins, a size-based separation to their subpopulations with AsFlFFF was introduced as a successive step. This enabled additional characterization of subpopulations by nanoparticle tracking analysis, western blotting, electron microscopy, capillary electrophoresis coupled with laser-induced fluorescent detection, zeta potential measurements, as well as free amino acids and glucose analysis with hydrophilic interaction liquid chromatography-tandem mass spectrometry. Finally, IAC was successfully on-line coupled to AsFlFFF, resulting in quick and automated isolation and fractionation of the subpopulations of EVs and lipoproteins. The constructed IAC-AsFlFFF system was able to process reliably 18–38 samples in 24 h with only minor operator involvement, resulting in highly reproducible and gentle fractionation of EV subpopulations in the size range of exomeres and exosomes. Polymeric monolithic disk columns were utilized for the first time for the IAC-based isolation of EVs and their subpopulations from human plasma, and for the detection of exomeres in CD9+ EVs and CD61+ platelet-derived EVs from human plasma samples. The results demonstrated that CD61+ EVs are potentially taking part in gluconeogenesis based on free amino acids and glucose present as cargo.
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2021
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Dually targeted bioinspired nanovesicle delays advanced prostate cancer tumour growth in vivo
Prostate cancer (PC) is second-leading cancer in men, with limited treatment options available for men with advanced and metastatic PC. Prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) have been exploited as therapeutic targets in PC due to their upregulation in the advanced stages of the disease. To date, several PSA- and PSMA-activatable prodrugs have been developed to reduce the systemic toxicity of existing chemotherapeutics. Bioinspired nanovesicles have been exploited in drug delivery, offering prolonged drug blood circulation and higher tumour accumulation. For the first time, this study describes the engineering of dually targeted PSA/PSMA nanovesicles for advanced PC. PSMA-targeted bioinspired hybrids were prepared by hydrating a lipid film with anti-PSMA-U937 cell membranes and DOX-PSA prodrug, followed by extrusion. The bioinspired hybrids were characterised using dynamic light scattering, transmission electron microscopy, Dot blot, flow cytometry and Western blot. Cellular binding and toxicity studies in PC cancer cell lines were carried out using flow cytometry, confocal microscopy, and resazurin assay. Finally, tumour targeting and therapeutic efficacy studies were performed in solid and metastatic C4-2B-tumor-bearing mice. Interestingly, our PSMA-targeted hybrids demonstrated high cell uptake in PSMA-expressing cells with significant accumulation in solid and metastatic C4-2B tumour tissues following intravenous administration. More promisingly, our dually targeted PSA/PSMA hybrid significantly slowed down the C4-2B tumour growth in vivo, compared to free DOX-PSA and non-targeted PSA-hybrid. Our PSA/PSMA bioinspired hybrid could offer a highly selective treatment for advanced PC with lower side effects. Statement of significance This study investigates a new approach to treat prostate cancer using dually targeted bioinspired nanovesicle . Our bioinspired vesicles are made mainly of a human blood cell membrane with a ligand recognising a specific marker (PSMA) on the surface of the prostate cancer cells. The present work describes the successful loading of a doxorubicin prodrug linked to a PSA- activatable peptide into these targeted bioinspired nanovesicle , where the active PSA enzyme presents in these cells converts the drug to its active form. Our dually targeted PSA/PSMA hybrid vesicles has successfully improved site-specific prodrug delivery to tackle advanced prostate cancer, offering a novel and effective prostate cancer treatment.
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2021
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Enhancing the Stabilization Potential of Lyophilization for Extracellular Vesicles
Extracellular vesicles (EV) are an emerging technology as immune therapeutics and drug delivery vehicles. However, EVs are usually stored at −80 °C which limits potential clinical applicability. Freeze-drying of EVs striving for long-term stable formulations is therefore studied. The most appropriate formulation parameters are identified in freeze-thawing studies with two different EV types. After a freeze-drying feasibility study, four lyophilized EV formulations are tested for storage stability for up to 6 months. Freeze-thawing studies revealed improved colloidal EV stability in presence of sucrose or potassium phosphate buffer instead of sodium phosphate buffer or phosphate-buffered saline. Less aggregation and/or vesicle fusion occurred at neutral pH compared to slightly acidic or alkaline pH. EVs colloidal stability can be most effectively preserved by addition of low amounts of poloxamer 188. Polyvinyl pyrrolidone failed to preserve EVs upon freeze-drying. Particle size and concentration of EVs are retained over 6 months at 40 °C in lyophilizates containing 10 mm K- or Na-phosphate buffer, 0.02% poloxamer 188, and 5% sucrose. The biological activity of associated beta-glucuronidase is maintained for 1 month, but decreased after 6 months. Here optimized parameters for lyophilization of EVs that contribute to generate long-term stable EV formulations are presented.
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2021
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Estradiol driven metabolism in transwomen associates with reduced circulating extracellular vesicle microRNA-224/452
Objective Sex steroid hormones like estrogens have a key role in the regulation of energy homeostasis and metabolism. In transwomen, gender-affirming hormone therapy like estradiol (in combination with antiandrogenic compounds) could affect metabolism as well. Given that the underlying pathophysiological mechanisms are not fully understood, this study assessed circulating estradiol-driven microRNAs (miRs) in transwomen and their regulation of genes involved in metabolism in mice. Methods Following plasma miR-sequencing (seq) in a transwomen discovery (n = 20) and validation cohort (n = 30), we identified miR-224 and miR-452. Subsequent systemic silencing of these miRs in male C57Bl/6 J mice (n = 10) was followed by RNA-seq-based gene expression analysis of brown and white adipose tissue in conjunction with mechanistic studies in cultured adipocytes. Results Estradiol in transwomen lowered plasma miR-224 and -452 carried in extracellular vesicles (EVs) while their systemic silencing in mice and cultured adipocytes increased lipogenesis (white adipose) but reduced glucose uptake and mitochondrial respiration (brown adipose). In white and brown adipose tissue, differentially expressed (miR target) genes are associated with lipogenesis (white adipose) and mitochondrial respiration and glucose uptake (brown adipose). Conclusion This study identified an estradiol-drive post-transcriptional network that could potentially offer a mechanistic understanding of metabolism following gender-affirming estradiol therapy.
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2021
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Evidence of Immune Modulators in the Secretome of the Equine Tapeworm Anoplocephala perfoliata
Anoplocephala perfoliata is a neglected gastro-intestinal tapeworm, commonly infecting horses worldwide. Molecular investigation of A. perfoliata is hampered by a lack of tools to better understand the host–parasite interface. This interface is likely influenced by parasite derived immune modulators released in the secretome as free proteins or components of extracellular vesicles (EVs). Therefore, adult RNA was sequenced and de novo assembled to generate the first A. perfoliata transcriptome. In addition, excretory secretory products (ESP) from adult A. perfoliata were collected and EVs isolated using size exclusion chromatography, prior to proteomic analysis of the EVs, the EV surface and EV depleted ESP. Transcriptome analysis revealed 454 sequences homologous to known helminth immune modulators including two novel Sigma class GSTs, five α-HSP90s, and three α-enolases with isoforms of all three observed within the proteomic analysis of the secretome. Furthermore, secretome proteomics identified common helminth proteins across each sample with known EV markers, such as annexins and tetraspanins, observed in EV fractions. Importantly, 49 of the 454 putative immune modulators were identified across the secretome proteomics contained within and on the surface of EVs in addition to those identified in free ESP. This work provides the molecular tools for A. perfoliata to reveal key players in the host–parasite interaction within the horse host.
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2021
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Evidence of Immune Modulators in the Secretome of the Equine Tapeworm Anoplocephala perfoliata. Pathogens 2021, 10, 912
Anoplocephala perfoliata is a neglected gastro-intestinal tapeworm, commonly infecting horses worldwide. Molecular investigation of A. perfoliata is hampered by a lack of tools to better understand the host–parasite interface. This interface is likely influenced by parasite derived immune modulators released in the secretome as free proteins or components of extracellular vesicles (EVs). Therefore, adult RNA was sequenced and de novo assembled to generate the first A. perfoliata transcriptome. In addition, excretory secretory products (ESP) from adult A. perfoliata were collected and EVs isolated using size exclusion chromatography, prior to proteomic analysis of the EVs, the EV surface and EV depleted ESP. Transcriptome analysis revealed 454 sequences homologous to known helminth immune modulators including two novel Sigma class GSTs, five α-HSP90s, and three α-enolases with isoforms of all three observed within the proteomic analysis of the secretome. Furthermore, secretome proteomics identified common helminth proteins across each sample with known EV markers, such as annexins and tetraspanins, observed in EV fractions. Importantly, 49 of the 454 putative immune modulators were identified across the secretome proteomics contained within and on the surface of EVs in addition to those identified in free ESP. This work provides the molecular tools for A. perfoliata to reveal key players in the host–parasite interaction within the horse host.
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2021
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Exosome-mediated mRNA delivery for SARS-CoV-2 vaccination
Background In less than a year from its zoonotic entry into the human population, SARS-CoV-2 has infected more than 45 million people, caused 1.2 million deaths, and induced widespread societal disruption. Leading SARS-CoV-2 vaccine candidates immunize with the viral spike protein delivered on viral vectors, encoded by injected mRNAs, or as purified protein. Here we describe a different approach to SARS-CoV-2 vaccine development that uses exosomes to deliver mRNAs that encode antigens from multiple SARS-CoV-2 structural proteins. Approach Exosomes were purified and loaded with mRNAs designed to express (i) an artificial fusion protein, LSNME, that contains portions of the viral spike, nucleocapsid, membrane, and envelope proteins, and (ii) a functional form of spike. The resulting combinatorial vaccine, LSNME/SW1, was injected into thirteen weeks-old, male C57BL/6J mice, followed by interrogation of humoral and cellular immune responses to the SARS-CoV-2 nucleocapsid and spike proteins, as well as hematological and histological analysis to interrogate animals for possible adverse effects. Results Immunized mice developed CD4+, and CD8+ T-cell reactivities that respond to both the SARS-CoV-2 nucelocapsid protein and the SARS-CoV-2 spike protein. These responses were apparent nearly two months after the conclusion of vaccination, as expected for a durable response to vaccination. In addition, the spike-reactive CD4+ T-cells response was associated with elevated expression of interferon gamma, indicative of a Th1 response, and a lesser induction of interleukin 4, a Th2-associated cytokine. Vaccinated mice showed no sign of altered growth, injection-site hypersensitivity, change in white blood cell profiles, or alterations in organ morphology. Consistent with these results, we also detected moderate but sustained anti-nucleocapsid and anti-spike antibodies in the plasma of vaccinated animals. Conclusion Taken together, these results validate the use of exosomes for delivering functional mRNAs into target cells in vitro and in vivo, and more specifically, establish that the LSNME/SW1 vaccine induced broad immunity to multiple SARS-CoV-2 proteins. Competing Interest Statement S.J.G is a paid consultant for Capricor, holds equity in Capricor, and is co-inventor of intellectual property licensed by Capricor. S.J.T. is co-inventor of intellectual property licensed by Capricor. C.G. is co-inventor of intellectual property licensed by Capricor. N.A. is an employee of Capricor.
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2021
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Exosomes for Wound Treatment: Purification Optimization, Bioactive Components Identification and Drug Loading
The application of exosomes as therapeutic agents and drug delivery systems has gained increasing popularity over the last decades owing to their natural functions in intercellular communication processes. Exosomes are nanosized membrane vesicles of endosomal origin, which are constitutively released by cells into the extracellular space. They consist of functional proteins, nucleic acids and lipids, which enable them to imitate the biological functions of their producing parent cells. While proteins and nucleic acids have been identified as key players in the biological activity of exosomes, potential contributions of constitutional lipids to these effects remain largely unknown. Moreover, the purification process of exosomes continues to be a critical issue in exosome research since the definition of standardized exosome purification conditions is still pending. Several isolation methods are currently available, yet their potential impact on the exosome functionality has been rarely assessed in sufficient detail. Finally, when investigated as drug delivery platforms, mostly hydrophobic drugs have been loaded into exosomes, therefore leaving the loading capacity of current processes for hydrophilic classical drugs largely unaddressed. Furthermore, the impact of the loading methods on the exosome integrity and intrinsic bioactivity remains incompletely understood as the vesicle characterization is often restricted to analyzing their basic physicochemical properties and cellular uptake as well as monitoring the drug response. This thesis is aimed at addressing central questions related to the characterization of stem cell-derived exosomes as therapeutic entities and drug carriers, mainly in the context of wound healing. The major objectives specifically encompass 1) the optimization of exosome production and purification parameters, and an investigation of their effect on the exosome properties, 2) the identification of the role of selected exosomal components in processes required for wound healing, and 3) a comprehensive appraisal of the impact of several drug loading methods on the exosome integrity and functionality. Chapter 1 introduces the research field of exosomes and presents currently available purification methods. Moreover, the therapeutic applications of stem cell-derived exosomes are portrayed, focusing on their potential use in wound healing. Chapter 2 presents a synopsis of currently available synthetic carriers and exosomes as drug delivery platforms. In addition, drug encapsulation techniques for exosomes are presented and discussed. In Chapter 3, a standardized exosome preparation protocol is described. Special attention was paid to the interplay between production/purification conditions and exosome 2 characteristics to ultimately establish the optimal conditions delivering a high yield of bioactive exosomes. Subsequently, the activity of stem cell-derived exosomes in skin wound healing was assessed both in vitro and in vivo. The potential involvement of the transmembrane enzyme CD73 and exosomal lipids in the wound healing-promoting effects of stem cell exosomes was reported. It was found that the extent of the different exosome components’ activities was dependent on the target cell type. Specifically, CD73 contributed significantly to the in vitro migratory/mitogenic activity of stem cell exosomes on keratinocytes, but had no effect on endothelial cells. Exosomal lipids, on the other hand, were involved in the in vitro and in vivo activity of stem cell exosomes in blood vessel formation and maturation, but did not promote proliferation/migration of keratinocytes or fibroblasts in vitro. Chapter 4 explores processes for the encapsulation of non-membrane permeable hydrophilic low molecular weight compounds (i.e. pyranine and pentoxifylline) into exosomes. The loading efficiency of several methods was compared, and the osmotic shock procedure was identified as the most efficient one. Subsequently, the potential impact of the loading processes on the functionality of stem cell-derived exosomes was assessed using physicochemical characterization and biological activity methods. Only two out of five tested encapsulation processes (i.e. freeze-thawing and osmotic shock) preserved the structural and biological integrity of stem cell exosomes. In Chapter 5, the main findings of the current work are recapitulated and discussed. In addition, an outlook on yet unsolved challenges in the exosome research area is provided.
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2021
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Extracellular vesicle analysis allows for identification of invasive IPMN
Background and Aims Advances in cross-sectional imaging have resulted in increased detection of intraductal papillary mucinous neoplasms (IPMNs), and their management remains controversial. At present, there is no reliable noninvasive method to distinguish between indolent and high risk IPMNs. We performed extracellular vesicle (EV) analysis to identify markers of malignancy in an attempt to better stratify these lesions. Methods Using a novel ultrasensitive digital extracellular vesicle screening technique (DEST), we measured putative biomarkers of malignancy (MUC1, MUC2, MUC4, MUC5AC, MUC6, Das-1, STMN1, TSP1, TSP2, EGFR, EpCAM, GPC1, WNT-2, EphA2, S100A4, PSCA, MUC13, ZEB1, PLEC1, HOOK1, PTPN6, and FBN1) in EV from patient-derived cell lines and then on circulating EV obtained from peripheral blood drawn from patients with IPMNs. We enrolled a total of 133 patients in two separate cohorts: a clinical discovery cohort (n = 86) and a validation cohort (n = 47). Results From 16 validated EV proteins in plasma samples collected from the discovery cohort, only MUC5AC showed significantly higher levels in high-grade lesions. Of the 11 patients with invasive IPMN (inv/HG), 9 had high MUC5AC expression in plasma EV of the 11 patients with high-grade dysplasia alone, only 1 had high MUC5AC expression (sensitivity of 82%, specificity of 100%). These findings were corroborated in a separate validation cohort. The addition of MUC5AC as a biomarker to imaging and high-risk stigmata allowed detection of all cases requiring surgery, whereas imaging and high-risk stigmata alone would have missed 5 of 14 cases (36%). Conclusions MUC5AC in circulating EV can predict the presence of invasive carcinoma within IPMN. This approach has the potential to improve the management and follow-up of patients with IPMN including avoiding unnecessary surgery.
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2021
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Extracellular vesicle‐mediated endothelial apoptosis and EV‐associated proteins correlate with COVID‐19 disease severity
Coronavirus disease-2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has lead to a global pandemic with a rising toll in infections and deaths. Better understanding of its pathogenesis will greatly improve the outcomes and treatment of affected patients. Here we compared the inflammatory and cardiovascular disease-related protein cargo of circulating large and small extracellular vesicles (EVs) from 84 hospitalized patients infected with SARS-CoV-2 with different stages of disease severity. Our findings reveal significant enrichment of proinflammatory, procoagulation, immunoregulatory and tissue-remodelling protein signatures in EVs, which remarkably distinguished symptomatic COVID-19 patients from uninfected controls with matched comorbidities and delineated those with moderate disease from those who were critically ill. Specifically, EN-RAGE, followed by TF and IL-18R1, showed the strongest correlation with disease severity and length of hospitalization. Importantly, EVs from COVID-19 patients induced apoptosis of pulmonary microvascular endothelial cells in the order of disease severity. In conclusion, our findings support a role for EVs in the pathogenesis of COVID-19 disease and underpin the development of EV-based approaches to predicting disease severity, determining need for patient hospitalization and identifying new therapeutic targets.
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2021
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Extracellular vesicles, lipids, and lipoproteins in early pregnant sheep
In sheep, pregnancy establishment encompasses conceptus elongation, implantation, and placentation. These events are regulated by factors present within the uterine luminal fluid (ULF) from the endometrial epithelium and the conceptus itself that affect proliferation, migration, attachment, and adhesion of the conceptus trophectoderm. As the peri-implantation period is especially susceptible to pregnancy loss, it is essential to understand the various components and functional roles of substances within the ULF. The central hypothesis of this dissertation is that lipids and lipid associated macromolecules are components of the ULF and mediate endometrial-embryonic crosstalk and regulate conceptus development. This work sought to identify, characterize, and/or determine the roles of: (1) extracellular vesicles (EVs); (2) lipids and metabolites; (3) prostaglandins (PGs); and (4) apolipoproteins present within the ULF of ewes during early gestation. Collectively, the present studies established that: (1) EVs increase within the ULF during the estrous cycle but are depleted in the uterine lumen of pregnant ewes due to uptake by the elongating conceptus; (2) the lipid and protein cargo of uterine EVs is diverse and altered by pregnancy; (3) uterine EVs regulate cellular processes in the conceptus trophectoderm and endometrium including cell proliferation and secretions; (4) various lipids (specifically phospholipids, ceramides, and triglycerides) and metabolites are elevated in the ULF of pregnant ewes; (5) the conceptus lipidome and metabolome is distinct from the ULF and endometrium suggesting selective uptake of ULF substances; (6) the production of PGs by PTGS2 in the conceptus is not required for conceptus elongation; (7) the secretion of APOA1 by the conceptus does not mobilize endometrial lipids into the ULF and is not required for early pregnancy development or survival. Collectively, these studies highlight the complex and dynamic composition of the ULF and support the overall hypothesis that lipids and lipid-associated macromolecules are critical components of the ULF that mediate conceptus-endometrial crosstalk and regulate important developmental processes in the conceptus. Future investigation and expansion of these findings will fill crucial gaps in our knowledge of early pregnancy events and may provide biomarkers or help develop therapies to improve pregnancy outcomes and reproductive efficiency in agricultural species.
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2021
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General and mild modification of food-derived extracellular vesicles for enhanced cell targeting
Food-derived extracellular vesicles (FDEVs) have attracted increasing attention as potential delivery vehicles for therapeutic agents due to their desirable features such as excellent biocompatibility, easy accessibility and cost effectiveness. However, the intrinsic targeting capability of FDEVs is unsatisfactory compared to artificial nanoparticles or other source-derived EVs, which calls for efficient surface engineering strategies to equip them with specific ligands. Here we report a general and mild modification method via reduction of disulfide groups to maleimide reactive thiols. Taking milk-derived EVs (mEVs) as a model system, we demonstrated the feasibility for tethering various ligands on the surface without compromising the vesicular structures. Building an ultra-sensitive nano-flow cytometer (nFCM), the heterogeneous nature of the functionalized samples was revealed, and a magnetic separation approach was proposed accordingly to remove the as-observed non-EV particles. The cellular uptake and cytotoxicity experiments provided direct evidence showing an enhanced cell targeting and cargo delivery capability of the ligand conjugated mEVs. In addition, the in vivo imaging further proved the applicability of transferrin conjugation for increased tumor enrichment of mEVs. Collectively, this general and mild ligand conjugation method enables an efficient surface functionalization of FDEVs, which is of vital importance for enhanced targeting delivery.
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2021
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Identification and characterization of hADSC‐derived exosome proteins from different isolation methods
Exosomes are secreted into the extracellular space by most cell types and contain various molecular constituents, which play roles in many biological processes. Adipose-derived mesenchymal stem cells (ADSCs) can differentiate into a variety of cell types and secrete a series of paracrine factors through exosomes. ADSC-derived exosomes have shown diagnostic and therapeutic potential in many clinical diseases. The molecular components are critical for their mechanisms. Several methods have been developed for exosome purification, including ultracentrifugation, ultrafiltration, density gradient purification, size-based isolation, polymer precipitation and immuno-affinity purification. Thus, we employed four methods to isolate exosomes from the hADSC culture medium, including ultracentrifugation, size exclusion chromatography, ExoQuick-TC precipitation and ExoQuick-TC ULTRA isolation. Following exosome isolation, we performed quantitative proteomic analysis of the exosome proteins using isobaric tags for relative and absolute quantification (iTRAQ) labelling, combined with 2D-LC-MS/MS. There were 599 universal and 138 stably expressed proteins in hADSC-derived exosomes. We proved that these proteins were potential hADSC-derived exosomes markers, including CD109, CD166, HSPA4, TRAP1, RAB2A, RAB11B and RAB14. From the quantitative proteomic analysis, we demonstrated that hADSC-derived exosome protein expression varied, with lipopolysaccharide (LPS) treatment, in the different isolation methods. Pathway analysis and proliferation, migration and endothelial tube formation assays showed varying effects in cells stimulated with hADSC-derived exosomes from different isolation methods. Our study revealed that different isolation methods might introduce variations in the protein composition in exosomes, which reflects their effects on biological function. The pros and cons of these methods are important points to consider for downstream research applications.
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2021
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Importance of between and within Subject Variability in Extracellular Vesicle Abundance and Cargo when Performing Biomarker Analyses
Small extracellular vesicles (sEV) have emerged as a potential rich source of biomarkers in human blood and present the intriguing potential for a ‘liquid biopsy’ to track disease and the effectiveness of interventions. Recently, we have further demonstrated the potential for EV derived biomarkers to account for variability in drug exposure. This study sought to evaluate the variability in abundance and cargo of global and liver-specific circulating sEV, within (diurnal) and between individuals in a cohort of healthy subjects (n = 10). We present normal ranges for EV concentration and size and expression of generic EV protein markers and the liver-specific asialoglycoprotein receptor 1 (ASGR1) in samples collected in the morning and afternoon. EV abundance and cargo was generally not affected by fasting, except CD9 which exhibited a statistically significant increase (p = 0.018). Diurnal variability was observed in the expression of CD81 and ASGR1, which significantly decreased (p = 0.011) and increased (p = 0.009), respectively. These results have potential implications for study sampling protocols and normalisation of biomarker data when considering the expression of sEV derived cargo as a biomarker strategy. Specifically, the novel finding that liver-specific EVs exhibit diurnal variability in healthy subjects should have broad implications in the study of drug metabolism and development of minimally invasive biomarkers for liver disease.
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2021
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Importance of extracellular vesicle secretion at the blood–cerebrospinal fluid interface in the pathogenesis of Alzheimer's disease
Increasing evidence indicates that extracellular vesicles (EVs) play an important role in the pathogenesis of Alzheimer’s disease (AD). We previously reported that the blood–cerebrospinal fluid (CSF) interface, formed by the choroid plexus epithelial (CPE) cells, releases an increased amount of EVs into the CSF in response to peripheral inflammation. Here, we studied the importance of CP-mediated EV release in AD pathogenesis. We observed increased EV levels in the CSF of young transgenic APP/PS1 mice which correlated with high amyloid beta (Aβ) CSF levels at this age. The intracerebroventricular (icv) injection of Aβ oligomers (AβO) in wild-type mice revealed a significant increase of EVs in the CSF, signifying that the presence of CSF-AβO is sufficient to induce increased EV secretion. Using in vivo, in vitro and ex vivo approaches, we identified the CP as a major source of the CSF-EVs. Interestingly, AβO-induced, CP-derived EVs induced pro-inflammatory effects in mixed cortical cultures. Proteome analysis of these EVs revealed the presence of several pro-inflammatory proteins, including the complement protein C3. Strikingly, inhibition of EV production using GW4869 resulted in protection against acute AβO-induced cognitive decline. Further research into the underlying mechanisms of this EV secretion might open up novel therapeutic strategies to impact the pathogenesis and progression of AD.
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2021
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Investigating The Role Of Extracellular Vesicles And MicroRNA-155 In Cerebrovascular Function In Inflammation
Blood-brain barrier (BBB) dysfunction is an early feature of several central nervous system (CNS) pathologies and is characterised by increased leukocyte migration to the CNS and increased paracellular permeability of brain endothelial cells (BECs). The mechanisms by which the BBB actively participates in the inflammatory events that contribute to the progression of many CNS diseases is still poorly understood. Extracellular vesicles (EVs) are a novel mechanism of cell-to-cell communication. Endothelial cell-derived EVs are upregulated in circulating blood in different pathologies (e.g. multiple sclerosis) and systemic inflammation. TNFα-stimulated BECs secrete a higher number of EVs, which carry a pro-inflammatory cargo. However, the role of cerebrovascular EVs modulating inflammation at the BBB is still unclear. In this project, EVs secreted from BECs were characterised based on number, size and RNA cargo. Indeed, BECs secreted higher number of EVs in inflammation that carried pro-inflammatory modulators (e.g. miRNA-155). Uptake of EVs by NVU cells and their role in BEC function was investigated. Interestingly, EVs decreased transendothelial resistance and increased T cell adhesion to BECs via up-regulation of adhesion molecules. TNFα/IFNγ–mediated BECs dysfunction is partially modulated by miRNA-155. However, the mechanism by which miRNA-155 modulates T cell adhesion remains to be elucidated. WNK1 was identified as possible target of miRNA-155 and shown to modulate T cell adhesion. Finally, unexpected increased polydipsia in female aged miRNA-155 knock-out mice was investigated but this unexpected phenotype was attributed to a miRNA-155-independent pathway. Results from this work constitute the first evidence that BEC-derived EVs modulate BBB function in inflammation, which is likely to be a mechanism of the cells to amplify pro-inflammatory cytokine signalling in the vasculature. Additionally, this work has demonstrated endothelial WNK1 as a modulator of T cell adhesion. Genotyping tissue from miRNA-155 KO mice will serve for future identification of novel modulators of water balance.
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2021
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Isolation and characterization of equine uterine extracellular vesicles: a comparative methodological study
Extracellular vesicles (EVs) have been identified in the uterine fluid in different species and have been pointed as key players in the embryo-maternal dialogue, maternal recognition of pregnancy and establishment of pregnancy. However, little is known about the uterine EVs in the mare. Therefore, the present study aimed at characterizing EVs from uterine lavage of cyclic mares by comparing five EVs isolation methods and the combination of them: (1) ultracentrifugation (UC); (2) concentration of lavage volume by Centricon ultrafiltration (CE); (3) the use of CE with different washing steps (phosphate-buffered saline with or without trehalose); (4) size-exclusion chromatography with iZON-qEV columns, and (5) a combination of the methods with best results based on EVs yield, purity, and protein cargo profiles. Transmission electron microscopy and Western blotting confirmed the isolation of EVs by all methods but with quantitative and qualitative differences. Mass spectrometry provided differences in protein profiles between methods, number of identified proteins, and protein classes. Our results indicate that the combination of CE/trehalose/iZON/UC is an optimal method to isolate equine uterine EVs with good yield and purity that can be applied in future studies to determine the role of equine uterine EVs in embryo-maternal interactions.
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2021
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Isolation methodology is essential to the evaluation of the extracellular vesicle component of the senescence‐associated secretory phenotype
A hallmark of senescence is the acquisition of an enhanced secretome comprising inflammatory mediators and tissue remodelling agents – the senescence-associated secretory phenotype (SASP). Through the SASP, senescent cells are hypothesised to contribute to both ageing and pathologies associated with age. Whilst soluble factors have been the most widely investigated components of the SASP, there is growing evidence that small extracellular vesicles (EVs) comprise functionally important constituents. Thus, dissecting the contribution of the soluble SASP from the vesicular component is crucial to elucidating the functional significance of senescent cell derived EVs. Here, we take advantage of a systematic proteomics based approach to determine that soluble SASP factors co-isolate with EVs following differential ultracentrifugation (dUC). We present size-exclusion chromatography (SEC) as a method for separation of the soluble and vesicular components of the senescent secretome and thus EV purification. Furthermore, we demonstrate that SEC EVs isolated from senescent cells contribute to non-cell autonomous paracrine senescence. Therefore, this work emphasises the requirement for methodological rigor due to the propensity of SASP components to co-isolate during dUC and provides a framework for future investigations of the vesicular component of the SASP.
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2021
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Isolation of cabbage exosome-like nanovesicles and investigation of their biological activities in human cells
There are extensive studies on the applications of extracellular vesicles (EVs) produced in cell culture for therapeutic drug development. However, large quantities of EVs are needed for in vivo applications, which requires high production costs and time. Thus, the development of new EV sources is essential to facilitate their use. Accordingly, plant-derived exosome-like nanovesicles are an emerging alternative for culture-derived EVs. Until now, however, few studies have explored their biological functions and uses. Therefore, it is necessary to elucidate biological activities of plant-derived exosome-like nanovesicles and harness vesicles for biomedical applications. Herein, cabbage and red cabbage were used as nanovesicle sources owing to their easy cultivation. First, an efficient method for nanovesicle isolation from cabbage (Cabex) and red cabbage (Rabex) was developed. Furthermore, isolated nanovesicles were characterized, and their biological functions were assessed. Both Cabex and Rabex promoted mammalian cell proliferation and, interestingly, suppressed inflammation in immune cells and apoptosis in human keratinocytes and fibroblasts. Finally, therapeutic drugs were encapsulated in Cabex or Rabex and successfully delivered to human cells, demonstrating the potential of these vesicles as alternative drug delivery vehicles. Overall, the current results provide strong evidence for the wide application of Cabex and Rabex as novel therapeutic biomaterials.
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2021
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Isolation of extracellular vesicles with combined enrichment methods
Extracellular vesicles (EVs) are currently of tremendous interest in many research disciplines and EVs have potential for development of EV diagnostics or therapeutics. Most well-known single EV isolation methods have their particular advantages and disadvantages in terms of EV purity and EV yield. Combining EV isolation methods provides additional potential to improve the efficacy of both purity and yield. This review assesses the contribution and efficacy of using combined EV isolation methods by performing a two-step systematic literature analysis from all papers applying EV isolation in the year 2019. This resulted in an overview of the various methods being applied for EV isolations. A second database was generated for all studies within the first database that fairly compared multiple EV isolation methods by determining both EV purity and EV yield after isolation. From these databases it is shown that the most used EV isolation methods are not per definition the best methods based on EV purity or EV yield, indicating that more factors play a role in the choice which EV isolation method to choose than only the efficacy of the method. From the included studies it is shown that ~60% of all the included EV isolations were performed with combined EV isolation methods. The majority of EV isolations were performed with differential ultracentrifugation alone or in combination with differential ultrafiltration. When efficacy of EV isolation methods was determined in terms of EV purity and EV yield, combined EV isolation methods clearly outperformed single EV isolation methods, regardless of the type of starting material used. A recommended starting point would be the use of size-exclusion chromatography since this method, especially when combined with low-speed centrifugation, resulted in the highest EV purity, while still providing a reasonable EV yield.
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2021
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Isolation of intact extracellular vesicles from cryopreserved samples
Extracellular vesicles (EVs) have emerged as promising candidates in biomarker discovery and diagnostics. Protected by the lipid bilayer, the molecular content of EVs in diverse biofluids are protected from RNases and proteases in the surrounding environment that may rapidly degrade targets of interests. Nonetheless, cryopreservation of EV-containing samples to -80°C may expose the lipid bilayer to physical and biological stressors which may result in cryoinjury and contribute to changes in EV yield, function, or molecular cargo. In the present work, we systematically evaluate the effect of cryopreservation at -80°C for a relatively short duration of storage (up to 12 days) on plasma- and media-derived EV particle count and/or RNA yield/quality, as compared to paired fresh controls. On average, we found that the plasma-derived EV concentration of stored samples decreased to 23% of fresh samples. Further, this significant decrease in EV particle count was matched with a corresponding significant decrease in RNA yield whereby plasma-derived stored samples contained only 47–52% of the total RNA from fresh samples, depending on the extraction method used. Similarly, media-derived EVs showed a statistically significant decrease in RNA yield whereby stored samples were 58% of the total RNA from fresh samples. In contrast, we did not obtain clear evidence of decreased RNA quality through analysis of RNA traces. These results suggest that samples stored for up to 12 days can indeed produce high-quality RNA; however, we note that when directly comparing fresh versus cryopreserved samples without cryoprotective agents there are significant losses in total RNA. Finally, we demonstrate that the addition of the commonly used cryoprotectant agent, DMSO, alongside greater control of the rate of cooling/warming, can rescue EVs from damaging ice formation and improve RNA yield.
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2021
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Measuring particle concentration of multimodal synthetic reference materials and extracellular vesicles with orthogonal techniques: Who is up to the challenge?
The measurement of physicochemical properties of polydisperse complex biological samples, for example, extracellular vesicles, is critical to assess their quality, for example, resulting from their production and isolation methods. The community is gradually becoming aware of the need to combine multiple orthogonal techniques to perform a robust characterization of complex biological samples. Three pillars of critical quality attribute characterization of EVs are sizing, concentration measurement and phenotyping. The repeatable measurement of vesicle concentration is one of the key‐challenges that requires further efforts, in order to obtain comparable results by using different techniques and assure reproducibility. In this study, the performance of measuring the concentration of particles in the size range of 50–300 nm with complementary techniques is thoroughly investigated in a step‐by step approach of incremental complexity. The six applied techniques include multi‐angle dynamic light scattering (MADLS), asymmetric flow field flow fractionation coupled with multi‐angle light scattering (AF4‐MALS), centrifugal liquid sedimentation (CLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), and high‐sensitivity nano flow cytometry (nFCM). To achieve comparability, monomodal samples and complex polystyrene mixtures were used as particles of metrological interest, in order to check the suitability of each technique in the size and concentration range of interest, and to develop reliable post‐processing data protocols for the analysis. Subsequent complexity was introduced by testing liposomes as validation of the developed approaches with a known sample of physicochemical properties closer to EVs. Finally, the vesicles in EV containing plasma samples were analysed with all the tested techniques. The results presented here aim to shed some light into the requirements for the complex characterization of biological samples, as this is a critical need for quality assurance by the EV and regulatory community. Such efforts go with the view to contribute to both, set‐up reproducible and reliable characterization protocols, and comply with the Minimal Information for Studies of Extracellular Vesicles (MISEV) requirements.
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2021
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Milk exosomes with enhanced mucus penetrability for oral delivery of siRNA
Bovine milk-derived exosomes have recently emerged as a promising nano-vehicle for the encapsulation and delivery of macromolecular biotherapeutics. Here we engineer high purity bovine milk exosomes (mExo) with modular surface tunability for oral delivery of small interfering RNA (siRNA). We utilize a low-cost enrichment method combining casein chelation with differential ultracentrifugation followed by size exclusion chromatography, yielding mExo of high concentration and purity. Using in vitro models, we demonstrate that negatively charged hydrophobic mExos can penetrate multiple biological barriers to oral drug delivery. A hydrophilic polyethylene glycol (PEG) coating was introduced on the mExo surface via passive, stable hydrophobic insertion of a conjugated lipid tail, which significantly reduced mExo degradation in acidic gastric environment and enhanced their permeability through mucin by over 3× compared to unmodified mExo. Both mExo and PEG-mExo exhibited high uptake by intestinal epithelial cells and mediated functional intracellular delivery of siRNA, thereby suppressing the expression of the target green fluorescence protein (GFP) gene by up to 70%. We also show that cationic chemical transfection is significantly more efficient in loading siRNA into mExo than electroporation. The simplicity of isolating high purity mExo in high concentrations and equipping them with tunable surface properties, demonstrated here, paves way for the development of mExo as an effective, scalable platform technology for oral drug delivery of siRNA.
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2021
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Modulation of rumen microbes through extracellular vesicle released by the rumen fluke Calicophoron daubneyi
Parasite derived extracellular vesicles (EVs) have been proposed to play key roles in the establishment and maintenance of infection. Calicophoron daubneyi is a newly emerging parasite of livestock with many aspects of its underpinning biology yet to be resolved. This research is the first in-depth investigation of EVs released by adult C. daubneyi. EVs were successfully isolated using both differential centrifugation and size exclusion chromatography (SEC), and morphologically characterized though transmission electron microscopy (TEM). EV protein components were characterized using a GeLC approach allowing the elucidation of comprehensive proteomic profiles for both their soluble protein cargo and surface membrane bound proteins yielding a total of 378 soluble proteins identified. Notably, EVs contained Sigma-class GST and cathepsin L and B proteases, which have previously been described in immune modulation and successful establishment of parasitic flatworm infections. SEC purified C. daubneyi EVs were observed to modulate rumen bacterial populations by likely increasing microbial species diversity via antimicrobial activity. This data indicates EVs released from adult C. daubneyi have a role in establishment within the rumen through the regulation of microbial populations offering new routes to control rumen fluke infection and to develop molecular strategies to improve rumen efficiency.
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2021
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Molecular and functional profiling of apical versus basolateral small extracellular vesicles derived from primary human proximal tubular epithelial cells under inflammatory conditions
Proximal tubular epithelial cells (PTEC) are central players in inflammatory kidney diseases. However, the complex signalling mechanism/s via which polarized PTEC mediate disease progression are poorly understood. Small extracellular vesicles (sEV), including exosomes, are recognized as fundamental components of cellular communication and signalling courtesy of their molecular cargo (lipids, microRNA, proteins). In this study, we examined the molecular content and function of sEV secreted from the apical versus basolateral surfaces of polarized human primary PTEC under inflammatory diseased conditions. PTEC were cultured under normal and inflammatory conditions on Transwell inserts to enable separate collection and isolation of apical/basolateral sEV. Significantly increased numbers of apical and basolateral sEV were secreted under inflammatory conditions compared with equivalent normal conditions. Multi-omics analysis revealed distinct molecular profiles (lipids, microRNA, proteins) between inflammatory and normal conditions for both apical and basolateral sEV. Biological pathway analyses of significantly differentially expressed molecules associated apical inflammatory sEV with processes of cell survival and immunological disease, while basolateral inflammatory sEV were linked to pathways of immune cell trafficking and cell-to-cell signalling. In line with this mechanistic concept, functional assays demonstrated significantly increased production of chemokines (monocyte chemoattractant protein-1, interleukin-8) and immuno-regulatory cytokine interleukin-10 by peripheral blood mononuclear cells activated with basolateral sEV derived from inflammatory PTEC. We propose that the distinct molecular composition of sEV released from the apical versus basolateral membranes of human inflammatory PTEC may reflect specialized functional roles, with basolateral-derived sEV pivotal in modulating tubulointerstitial inflammatory responses observed in many immune-mediated kidney diseases. These findings provide a rationale to further evaluate these sEV-mediated inflammatory pathways as targets for biomarker and therapeutic development.
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2021
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Multiplexed electrokinetic sensor for detection and therapy monitoring of extracellular vesicles from liquid biopsies of non-small-cell lung cancer patients
Liquid biopsies based on extracellular vesicle (EV) protein profiles represent a promising tool for treatment monitoring of tumors, including non-small-cell lung cancers (NSCLC). In this study, we present the development of an electrokinetic sensor for multiplexed surface protein profiling of EVs and analysis of clinical samples. The method detects the difference in the streaming current obtained as a result of EV binding to the inner surface of a functionalized microcapillary, thereby estimating the expression level of a surface marker. Using multiple microchannels functionalized with different antibodies in a parallel fluidic connection, we first demonstrate the capacity for simultaneous detection of multiple surface markers in small EVs (sEVs) from NSCLC cells. To investigate the prospects of liquid biopsies based on EVs, we then apply the method to profile sEVs isolated from the pleural effusion (PE) fluids of three NSCLC adenocarcinoma patients with different genomic alterations (ALK-fusion, KRAS and EGFR) and applied treatments (chemotherapy, EGFR or ALK tyrosine kinase inhibitors). These vesicles were targeted against CD9 tetraspanin, as well as EGFR and PD-L1, two markers of interest in NSCLC. The electrokinetic signals showed detection of these markers on sEVs yet highlighting distinct interpatient differences, e.g., increased EGFR levels in sEVs from a patient with EGFR mutation as compared to an ALK-mutant one. The sensors also detected differences in PD-L1 expressions, in line with those measured by complementary methods. The analysis of sEVs from a patient prior and post crizotinib treatment also revealed a significant increase in the expression of some markers, e.g. EGFR and PD-L1. The obtained results hold promise for the application of the method for tumor treatment monitoring based on sEVs from liquid biopsies.
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2021
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Neutralizing antibody evasion and transduction with purified extracellular vesicle-enveloped AAV vectors.
Adeno-associated virus (AAV) is classified as a non-enveloped DNA virus. However, several years ago we discovered that in media of packaging cells producing recombinant AAV vectors, AAV capsids can associate with the interior and surface of extracellular vesicles (EVs), sometimes referred to as exosomes. Since then we and others have demonstrated that exosome-enveloped AAV, exo-AAV, can enhance transduction in vivo as well as evade neutralizing antibodies. While promising, these data were generated with differential centrifugation to pellet the exo-AAV. This method results in a heterogeneous mixture of exo-AAV, co-precipitating proteins, as well as free AAV capsids. To define the properties of exo-AAV more accurately, here we used a density gradient method to purify exo-AAV. We next performed head-to-head comparisons of standard AAV1, differential centrifuged exo-AAV1, and gradient purified exo-AAV1 for antibody evasion and transgene expression in the murine brain. We found purified exo-AAV1 to be more resistant to neutralizing antibodies than the other AAV preparations. Direct intracranial injection of purified exo-AAV1 into mice resulted in robust transduction, which transduced a larger area of brain than standard AAV1. We also identified the recently described membrane-associated accessory protein (MAAP) by mass spectrometry of purified exo-AAV1 preparations. Finally, we used a scalable method, size-exclusion chromatography to isolate exo-AAV1, and demonstrated functional transduction in cultured cells and increased antibody resistance. Together, these data suggest that higher purity exo-AAV will have beneficial characteristics for gene delivery and also may lead to mechanistic insights into the incorporation of AAV into EVs.
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2021
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Oncolytic virus purification with periodic counter‐current chromatography
Virus-based biologicals are one of the most promising biopharmaceuticals of the 21st century medicine and play a significant role in the development of innovative therapeutic, prophylactic, and clinical applications. Oncolytic virus manufacturing scale can range from 5 L in research and development up to 50 L for clinical studies and reach hundreds of liters for commercial scale. The inherent productivity and high integration potential of periodic counter-current chromatography (PCC) offer a transversal solution to decrease equipment footprint and the reduction of several non-value-added unit operations. We report on the design of an efficient PCC process applied to the intermediate purification of oncolytic adenovirus. The developed ion-exchange chromatographic purification method was carried out using a four-column setup for three different scenarios: (i) variation in the feedstock, (ii) potential use of a post-load washing step to improve virus recovery, and (iii) stability during extended operation. Obtained virus recoveries (57%–86%) and impurity reductions (>80% DNA, and >70% total protein) match or overcome batch purification. Regarding process stability and automation, our results show that not only the dynamic control strategy used is able to suppress perturbations in the sample inlet but also allows for unattended operation in the case of ion exchange capture.
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2021
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Parasite worm antigens instruct macrophages to release immunoregulatory extracellular vesicles
Emerging evidence suggests that immune cells not only communicate with each other through cytokines, chemokines, and cell surface receptors, but also by releasing small membranous structures known as extracellular vesicles (EVs). EVs carry a variety of different molecules that can be taken up by recipient cells. Parasitic worms are well known for their immunomodulatory properties, but whether they can affect immune responses by altering EV-driven communication between host immune cells remains unclear. Here we provide evidence that stimulation of bone marrow-derived macrophages (BMDMs) with soluble products of Trichuris suis (TSPs), leads to the release of EVs with anti-inflammatory properties. Specifically, we found that EVs from TSP-pulsed BMDMs, but not those from unstimulated BMDMs can suppress TNFα and IL-6 release in LPS-stimulated BMDMs and BMDCs. However, no polarization toward M1 or M2 was observed in macrophages exposed to EVs. Moreover, EVs enhanced reactive oxygen species (ROS) production in the exposed BMDMs, which was associated with a deregulated redox homeostasis as revealed by pathway analysis of transcriptomic data. Proteomic analysis identified cytochrome p450 (CYP450) as a potential source of ROS in EVs from TSP-pulsed BMDMs. Finally, pharmacological inhibition of CYP450 activity could suppress ROS production in those BMDMs. In summary, we find that TSPs can modulate immune responses not only via direct interactions but also indirectly by eliciting the release of EVs from BMDMs that exert anti-inflammatory effects on recipient cells.
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2021
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PD1 blockade potentiates the therapeutic efficacy of photothermally-activated and MRI-guided low temperature-sensitive magnetoliposomes
This study investigates the effect of PD1 blockade on the therapeutic efficacy of novel doxorubicin-loaded temperature-sensitive liposomes. Herein, we report photothermally-activated, low temperature-sensitive magnetoliposomes (mLTSL) for efficient drug delivery and magnetic resonance imaging (MRI). The mLTSL were prepared by embedding small nitrodopamine palmitate (NDPM)-coated iron oxide nanoparticles (IO NPs) in the lipid bilayer of low temperature-sensitive liposomes (LTSL), using lipid film hydration and extrusion. Doxorubicin (DOX)-loaded mLTSL were characterized using dynamic light scattering, differential scanning calorimetry, electron microscopy, spectrofluorimetry, and atomic absorption spectroscopy. Photothermal experiments using 808 nm laser irradiation were conducted. In vitro photothermal DOX release studies and cytotoxicity was assessed using flow cytometry and resazurin viability assay, respectively. In vivo DOX release and tumor accumulation of mLTSL(DOX) were assessed using fluorescence and MR imaging, respectively. Finally, the therapeutic efficacy of PD1 blockade in combination with photothermally-activated mLTSL(DOX) in CT26-tumor model was evaluated by monitoring tumor growth, cytokine release and immune cell infiltration in the tumor tissue. Interestingly, efficient photothermal heating was obtained by varying the IO NPs content and the laser power, where on-demand burst DOX release was achievable in vitro and in vivo. Moreover, our mLTSL exhibited promising MR imaging properties with high transverse r2 relaxivity (333 mM−1 s−1), resulting in superior MR imaging in vivo. Furthermore, mLTSL(DOX) therapeutic efficacy was potentiated in combination with anti-PD1 mAb, resulting in a significant reduction in CT26 tumor growth via immune cell activation. Our study highlights the potential of combining PD1 blockade with mLTSL(DOX), where the latter could facilitate chemo/photothermal therapy and MRI-guided drug delivery.
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2021
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Periodontal and Dental Pulp Cell-Derived Small Extracellular Vesicles: A Review of the Current Status
Extracellular vesicles (EVs) are membrane-bound lipid particles that are secreted by all cell types and function as cell-to-cell communicators through their cargos of protein, nucleic acid, lipids, and metabolites, which are derived from their parent cells. There is limited information on the isolation and the emerging therapeutic role of periodontal and dental pulp cell-derived small EVs (sEVs, <200 nm, or exosome). In this review, we discuss the biogenesis of three EV subtypes (sEVs, microvesicles and apoptotic bodies) and the emerging role of sEVs from periodontal ligament (stem) cells, gingival fibroblasts (or gingival mesenchymal stem cells) and dental pulp cells, and their therapeutic potential in vitro and in vivo. A review of the relevant methodology found that precipitation-based kits and ultracentrifugation are the two most common methods to isolate periodontal (dental pulp) cell sEVs. Periodontal (and pulp) cell sEVs range in size, from 40 nm to 2 μm, due to a lack of standardized isolation protocols. Nevertheless, our review found that these EVs possess anti-inflammatory, osteo/odontogenic, angiogenic and immunomodulatory functions in vitro and in vivo, via reported EV cargos of EV–miRNAs, EV–circRNAs, EV–mRNAs and EV–lncRNAs. This review highlights the considerable therapeutic potential of periodontal and dental pulp cell-derived sEVs in various regenerative applications.
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2021
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Plasma exosome microRNAs in patients with advanced renal cell carcinoma treated with nivolumab and ipilimumab: Potential biomarkers of response to therapy.
Background: There is a critical unmet need for predictive biomarkers in the management of metastatic renal cell carcinoma (mRCC). We sought to quantify plasma exosome microRNAs (miRNAs) and correlate with response to first line nivolumab and ipilimumab (N/I) to potentially serve as such a biomarker. Methods: We evaluated the expression of 11 miRNAs in 19 patients with mRCC (prior to initiation of N/I) and in 32 healthy volunteers. Exosomes were extracted from 500 uL of plasma (qEV original, Izon Science) and once confirmed, were used for miRNAs extraction. MiRNAs expression was evaluated by real time polymerase chain reaction using a TaqMan miRNA assay (Applied Biosystems). The relative quantity of each miRNA in patients was compared to healthy volunteers. The expression of each miRNA was correlated to the best response to N/I, categorizing patients as either responders or non-responders. Results: Clinical characteristics are summarized in the table below. Median age at the start of systemic therapy was 64.3 years. MiR200b demonstrated a significantly higher expression in mRCC patients than in healthy volunteers (unpaired t-test; p=0.04). We observed a variable pattern of miRNA expression based on response to N/I. Although not statistically significant, 4 miRNA (miR138, 155, 200b, 221) were upregulated in non-responders, while two (miR200a and 497) were upregulated in responders. Of note, the only patient to achieve a complete response had the lowest expression of miR138 and the highest expression of miR497. Conclusions: Although preliminary and limited by a small number of patients, these initial observational results are promising and suggest a potential role for miRNAs as predictive biomarkers in mRCC. MiR138 and 497 are known to regulate CTLA-4 and PD-L1, respectively. We speculate that these miRNA are potentially involved in response to immune checkpoint therapy. Ongoing work in evaluating expression of these and other miRNAs in blood and in tissue along with clinical correlation continues.
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2021
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Plasmonic nanobowtiefluidic device for sensitive detection of glioma extracellular vesicles by Raman spectrometry
Cancer cells shed into biofluids extracellular vesicles (EVs) — nanoscale membrane particles carrying diagnostic information. EVs shed by heterogeneous populations of tumor cells offer a unique opportunity to access biologically important aspects of disease complexity. Glioblastoma (GBM) exemplifies cancers that are incurable, because their temporal dynamics and molecular complexity evade standard diagnostic methods and confound therapeutic efforts. Liquid biopsy based on EVs offers unprecedented real-time access to complex tumour signatures, but it is not used clinically due to inefficient testing methods. We report on a nanostructured microfluidic-device that employs SERS for unambiguous identification of EVs from different GBM cell populations. The device features fabless plasmonic nanobowties for label-free and non-immunological SERS detection of EVs. This nanobowtiefluidic device combines the advanced characteristics of plasmonic nanobowties with a high throughput sample-delivery system for concentration of the analytes in the vicinity of the detection site. We showed theoretically and experimentally that the fluidic device assists the monolayer distribution of the EVs, which dramatically increase the probability of EV's existence in the laser illumination area. In addition, the optimized fabless nanobowtie structures with an average electric field enhancement factor of 9 × 105 achieve distinguishable and high intensity SERS signals. Using the nanobowtiefluidic and micro-Raman equipment, we were able to distinguish a library of peaks expressed in GBM EV subpopulations from two distinct glioblastoma cell lines (U373, U87) and compare them to those of non-cancerous glial EVs (NHA) and artificial homogenous vesicles (e.g. DOPC/Chol). This cost-effective and easy-to-fabricate SERS platform and a portable sample-delivery system for discerning the sub-population of GBM EVs and non-cancerous glial EVs may have broader applications to different types of cancer cells and their molecular/oncogenic signature.
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2021
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Pluripotent stem cell-induced skeletal muscle progenitor cells with givinostat promote myoangiogenesis and restore dystrophin in injured Duchenne dystrophic muscle
Background Duchenne muscular dystrophy (DMD) is caused by mutations of the gene that encodes the protein dystrophin. A loss of dystrophin leads to severe and progressive muscle wasting in both skeletal and heart muscles. Human induced pluripotent stem cells (hiPSCs) and their derivatives offer important opportunities to treat a number of diseases. Here, we investigated whether givinostat (Givi), a histone deacetylase inhibitor, with muscle differentiation properties could reprogram hiPSCs into muscle progenitor cells (MPC) for DMD treatment. Methods MPC were generated from hiPSCs by treatment with CHIR99021 and givinostat called Givi-MPC or with CHIR99021 and fibroblast growth factor as control-MPC. The proliferation and migration capacity were investigated by CCK-8, colony, and migration assays. Engraftment, pathological changes, and restoration of dystrophin were evaluated by in vivo transplantation of MPC. Conditioned medium from cultured MPC was collected and analyzed for extracellular vesicles (EVs). Results Givi-MPC exhibited superior proliferation and migration capacity compared to control-MPC. Givi-MPC produced less reactive oxygen species (ROS) after oxidative stress and insignificant expression of IL6 after TNF-α stimulation. Upon transplantation in cardiotoxin (CTX)-injured hind limb of Mdx/SCID mice, the Givi-MPC showed robust engraftment and restored dystrophin in the treated muscle than in those treated with control-MPC or human myoblasts. Givi-MPC significantly limited infiltration of inflammatory cells and reduced muscle necrosis and fibrosis. Additionally, Givi-MPC seeded the stem cell pool in the treated muscle. Moreover, EVs released from Givi-MPC were enriched in several miRNAs related to myoangiogenesis including miR-181a, miR-17, miR-210 and miR-107, and miR-19b compared with EVs from human myoblasts. Conclusions It is concluded that hiPSCs reprogrammed into MPC by givinostat possessing anti-oxidative, anti-inflammatory, and muscle gene-promoting properties effectively repaired injured muscle and restored dystrophin in the injured muscle.
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2021
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Potential of Exosomes for Diagnosis and Treatment of Joint Disease: Towards a Point-of-Care Therapy for Osteoarthritis of the Knee
In the knee joint, articular cartilage injury can often lead to osteoarthritis of the knee (OAK). Currently, no point-of-care treatment can completely address OAK symptoms and regenerate articular cartilage to restore original functions. While various cell-based therapies are being developed to address OAK, exosomes containing various components derived from their cells of origin have attracted attention as a cell-free alternative. The potential for exosomes as a novel point-of-care treatment for OAK has been studied extensively, especially in the context of intra-articular treatments. Specific exosomal microRNAs have been identified as possibly effective in treating cartilage defects. Additionally, exosomes have been studied as biomarkers through their differences in body fluid composition between joint disease patients and healthy subjects. Exosomes themselves can be utilized as a drug delivery system through their manipulation and encapsulation of specific contents to be delivered to specific cells. Through the combination of exosomes with tissue engineering, novel sustained release drug delivery systems are being developed. On the other hand, many of the functions and activities of exosomes are unknown and challenges remain for clinical applications. In this review, the possibilities of intra-articular treatments utilizing exosomes and the challenges in using exosomes in therapy are discussed.
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2021
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Potential role of plasma extracellular vesicles in microbial translocation and cardiovascular risk in people living with HIV and type 2 diabetes
Background: HIV and type 2 diabetes (T2D) are both associated with gut microbiota alterations, lowgrade endotoxemia and increased cardiovascular risk. We investigated the potential role of plasma extracellular vesicles (EVs) in relation to these processes. Materials and methods: Plasma EVs were isolated by size exclusion chromatography in fasting individuals with HIV and T2D (n=16), T2D only (n=14), HIV only (n=20) or healthy controls (n=19), and characterized by transmission electron microscopy, western blot, nanoparticle tracking analysis and quantitative proteomics. The ndings were compared to gut microbiota alterations, lipopolysaccharide levels and cardiovascular risk prole. Results: Individuals with concomitant HIV and T2D had higher plasma EV concentration, which correlated closely with plasma lipopolysaccharides, triglycerides and Framingham score, but not with gut microbiota alterations. Proteomic analyses identied 558 human proteins, largely related to cardiometabolic disease genes and upstream regulation of inammatory pathways, including IL-6 and IL1β, as well as 30 bacterial proteins, mostly from lipopolysaccharide-producing Proteobacteria. Conclusions: Our study supports that EVs are related to microbial translocation processes in individuals with HIV and T2D. Their proteomic content suggests a contributing role in low-grade inammation and cardiovascular risk development. The present approach for exploring gut-host crosstalk can potentially identify novel diagnostic biomarkers and therapeutic targets.
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2021
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Probing effects of additives on the filterability of oncolytic viruses via a microfiltration process
One major part of therapeutic oncolytic viruses (OV) manufacturing is a membrane-based process with a major challenge of membrane fouling and consequent product loss. A small-scale microfiltration setup was developed, allowing online transmembrane pressure (TMP) measurement through a constant flux filtration using a low volume of a representative OV solution (< 3 mL). Using this setup, the effects of different additives including various proteins (bovine serum albumin and alpha-lactalbumin) and organic polymers (polyethylene glycol and polyvinylpyrrolidone) on microfiltration of the OV solution were screened. Results demonstrated that examined proteins significantly decreased membrane fouling rates and increased the virus recoveries. An addition of 5% bovine serum albumin (BSA) to the virus solution increased the virus recovery about 6-times compared to microfiltration of the virus solution without any additive. In contrast, none of the organic polymers could imitate effects of the protein additives. In a separate set of experiment, to study effect of protein on the membrane surface, the membrane surface was pre-blocked using a BSA protein solution and then subsequently utilized to filter the virus solution. This result also demonstrated a significant increase in virus recovery through the blocked membrane, about 4-times higher virus recovery compared to a non-blocked membrane.
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2021
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Protein Composition of Circulating Extracellular Vesicles Immediately Changed by Particular Short Time of High-Intensity Interval Training Exercise
Introduction/Purpose: High-intensity interval training (HIIT) promotes various biological processes and metabolic effects in multiple organs, but the role of extracellular vesicles (EVs) released from a variety of cells is not fully understood during HIIT exercise (HIIT-Ex). We investigated the changes in circulating number and proteomic profile of EVs to assess the effect of HIIT-Ex. Methods: Seventeen young men (median age, 20 years) were enrolled in the study. Total duration of the HIIT-Ex was 4 min. Blood samples were collected from before HIIT-Ex (pre-HIIT-Ex), at the immediate conclusion of HIIT-Ex (T0), at 30 min (T30), and at 120 min after HIIT-Ex. The pulse rate and systolic blood pressure were measured. Circulating EVs were characterized, and EV proteins were detected via nano liquid chromatography tandem mass spectrometry. Results: The pulse rate and systolic blood pressure at T0 to pre-HIIT-Ex were significantly higher. Circulating EV number was significantly altered throughout the HIIT-Ex, and the source of circulating EVs included skeletal muscle, hepatocytes, and adipose tissue. Proteomic analysis identified a total of 558 proteins within isolated circulating EVs from pre-HIIT-Ex, T0, and T30. Twenty proteins in total were significantly changed at pre-HIIT-Ex, T0, and T30 and are involved in a variety of pathways, such as activation of coagulation cascades, cellular oxidant detoxification, and correction of acid–base imbalance. Catalase and peroxiredoxin II were increased at T0. Conclusion: The circulating EV composition can be immediately changed by particularly a short time of HIIT-Ex, indicating that EVs may intercommunicate across various organs rapidly in response to HIIT-Ex.
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2021
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Proteomic Analysis of Circulating Extracellular Vesicles Identifies Potential Biomarkers for Lymph Node Metastasis in Oral Tongue Squamous Cell Carcinoma
Lymph node metastasis is the most reliable indicator of a poor prognosis for patients with oral tongue cancers. Currently, there are no biomarkers to predict whether a cancer will spread in the future if it has not already spread at the time of diagnosis. The aim of this study was to quantitatively profile the proteomes of extracellular vesicles (EVs) isolated from blood samples taken from patients with oral tongue squamous cell carcinoma with and without lymph node involvement and non-cancer controls. EVs were enriched using size exclusion chromatography (SEC) from pooled plasma samples of patients with non-nodal and nodal oral tongue squamous cell carcinoma (OTSCC) and non-cancer controls. Protein cargo was quantitatively profiled using isobaric labelling (iTRAQ) and two-dimensional high-performance liquid chromatography followed by tandem mass spectrometry. We identified 208 EV associated proteins and, after filtering, generated a short list of 136 proteins. Over 85% of the EV-associated proteins were associated with the GO cellular compartment term “extracellular exosome”. Comparisons between non-cancer controls and oral tongue squamous cell carcinoma with and without lymph node involvement revealed 43 unique candidate EV-associated proteins with deregulated expression patterns. The shortlisted EV associated proteins described here may be useful discriminatory biomarkers for differentiating OTSCC with and without nodal disease or non-cancer controls.
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2021
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Proteomic Profiling of Exosomes From Hemorrhagic Moyamoya Disease and Dysfunction of Mitochondria in Endothelial Cells
Background and Purpose: Moyamoya disease (MMD) is a rare steno-occlusive and slowly progressing cerebrovascular disorder. The detailed mechanism of the underlying pathogenesis is still blurry. Methods: Tandem Mass Tag-labeled quantitative proteomics was performed on serum-derived exosomes (SDEs) extracted from adult patients diagnosed with pure ischemic MMD or hemorrhagic MMD and healthy controls. Then mouse brain vascular endothelial cell (EC), human umbilical vein EC, neuroblastoma cell, and human hepatocyte cell were treated with exosomes, and changes of the protein expression in mouse brain vascular EC cells were identified. Results: Proteomics analysis results showed that 859 shared proteins were detected in SDEs from ischemic and hemorrhagic MMD patients with 231 differently expressed compared with healthy controls. Bioinformatic analysis revealed dysregulated cell growth and maintenance and indicated disturbed actin dynamics in MMD, with CFL1 (Cofilin-1) and ACTR2/3 (actin-related protein 2/3; also known as ARP2/3) downregulated in ischemic and hemorrhagic patients’ SDEs. We also found immunity dysfunction in hemorrhagic MMD. Following treatment with MMD SDEs, mouse brain vascular EC cells showed significantly higher levels of proliferation and more ethynyl-2-deoxyuridine-positive cells compared with the healthy control group, while there were no obvious changes in the human umbilical vein EC and human hepatocyte cell. Interestingly, we also found that SDEs from ischemic MMD promoted neuroblastoma cell proliferation. Proteomic analysis of mouse brain vascular EC cells suggested that SDEs from hemorrhagic MMD patients induced dysfunction of the mitochondria in cerebrovascular ECs. Conclusions: This study highlighted potential molecular mechanisms underlying the pathogenesis of MMD patients, thereby providing new therapeutic strategies for MMD.
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2021
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Recent electrokinetic strategies for isolation, enrichment and separation of extracellular vesicles
Extracellular vesicles (EVs) are a family of cell-derived membrane vesicles that are present in almost all body fluids. EVs have gained significant interest over the last decades as mediators of key functions in numerous patho-physiological condition (clearance, signalling, trophic support, cargo delivery) and as potential prognostic or diagnostic biomarkers. The endogenous delivery capacities of these nanometric entities also hold a high potential as engineered drug nanocarriers for clinical and pharmaceutical applications, especially for targeted therapies. Nevertheless, knowledge about the features of individual EVs (composition, physical and chemical characteristics) is still at the infancy because of the technical challenges to purify and analyze the various subpopulations of EVs. In this review, a comprehensive overview of electrokinetically driven methods for isolation, enrichment and characterization of EVs is presented. This review covers new trends of analytical science (over 7 years up till 2020), serving for high-quality EVs production, isolation, analysis and quality control, which are expected to provide powerful and complementary alternatives to the conventional and recently emerged approaches such as microfluidics. We critically discuss here the pros and cons of the different instrumental and methodological developments for electrokinetic strategies applied to EVs.
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2021
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Secreted therapeutics: monitoring durability of microRNA-based gene therapies in the central nervous system
The preclinical development of microRNA-based gene therapies for inherited neurodegenerative diseases is accompanied by translational challenges. Due to the inaccessibility of the brain to periodically evaluate therapy effects, accessible and reliable biomarkers indicative of dosing, durability and therapeutic efficacy in the central nervous system are very much needed. This is particularly important for viral vector-based gene therapies, in which a one-time administration results in long-term expression of active therapeutic molecules in the brain. Recently, extracellular vesicles have been identified as carriers of RNA species, including microRNAs, and proteins in all biological fluids, whilst becoming potential sources of biomarkers for diagnosis. In this study, we investigated the secretion and potential use of circulating miRNAs associated with extracellular vesicles as suitable sources to monitor the expression and durability of gene therapies in the brain. Neuronal cells derived from induced pluripotent stem cells were treated with adeno-associated viral vector serotype 5 carrying an engineered microRNA targeting huntingtin or ataxin3 gene sequences, the diseases-causing genes of Huntington disease and spinocerebellar ataxia type 3, respectively. After treatment, the secretion of mature engineered microRNA molecules was confirmed, with extracellular microRNA levels correlating with viral dose and cellular microRNA expression in neurons. We further investigated the detection of engineered microRNAs over time in the CSF of non-human primates after a single intrastriatal injection of adeno-associated viral vector serotype 5 carrying a huntingtin-targeting engineered microRNA. Quantifiable engineered microRNA levels enriched in extracellular vesicles were detected in the CSF up to 2 years after brain infusion. Altogether, these results confirm the long-term expression of adeno-associated viral vector serotype 5-delivered microRNAs and support the use of extracellular vesicle-associated microRNAs as novel translational pharmacokinetic markers in ongoing clinical trials of gene therapies for neurodegenerative diseases.
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2021
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Serum extracellular vesicle-derived circHIPK3 and circSMARCA5 are two novel diagnostic biomarkers for glioblastoma multiforme
Glioblastoma multiforme (GBM) is the most frequent and deadly human brain cancer. Early diagnosis through non-invasive biomarkers may render GBM more easily treatable, improving the prognosis of this currently incurable disease. We suggest the use of serum extracellular vesicle (sEV)-derived circular RNAs (circRNAs) as highly stable minimally invasive diagnostic biomarkers for GBM diagnosis. EVs were isolated by size exclusion chromatography from sera of 23 GBM and 5 grade 3 glioma (GIII) patients, and 10 unaffected controls (UC). The expression of two candidate circRNAs (circSMARCA5 and circHIPK3) was assayed by droplet digital PCR. CircSMARCA5 and circHIPK3 were significantly less abundant in sEVs from GBM patients with respect to UC (fold-change (FC) of −2.15 and −1.92, respectively) and GIII (FC of −1.75 and −1.4, respectively). Receiver operating characteristic curve (ROC) analysis, based on the expression of sEV-derived circSMARCA5 and circHIPK3, allowed us to distinguish GBM from UC (area under the curve (AUC) 0.823 (0.667–0.979) and 0.855 (0.704 to 1.000), with a 95% confidence interval (CI), respectively). Multivariable ROC analysis, performed by combining the expression of sEV-derived circSMARCA5 and circHIPK3 with preoperative neutrophil to lymphocyte (NLR), platelet to lymphocyte (PLR) and lymphocyte to monocyte (LMR) ratios, three known diagnostic and prognostic GBM markers, allowed an improvement in the GBM diagnostic accuracy (AUC 0.901 (0.7912 to 1.000), 95% CI). Our data suggest sEV-derived circSMARCA5 and circHIPK3 as good diagnostic biomarkers for GBM, especially when associated with preoperative NLR, PLR and LMR.
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2021
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Single‐step equipment‐free extracellular vesicle concentration using super absorbent polymer beads
Extracellular vesicles (EVs) contain useful biomarkers for disease diagnosis and are promising biomaterials for the delivery of therapeutic molecules in vivo. Accordingly, an efficient concentration method is necessary for large-scale production or high-throughput isolation of EVs from bulk liquid samples, including culture medium and body fluids, to achieve their clinical application. However, current EV concentration methods, including ultrafiltration, are limited with respect to cost, efficiency, and centrifugation time. In this study, we developed the first single-step, equipment-free EV concentration method using super absorbent polymer (SAP) beads. SAP beads absorb small molecules, including water, via nano-sized channels but expel and thereby concentrate EVs. Consequently, the beads drastically enrich EVs by reducing the solution volume in a single step, without affecting EV characteristics. Moreover, the purity of the concentrated EV solution was high due to the absorption of protein impurities by SAP beads. To further demonstrate the versatility of the method, we showed that SAP beads successfully enrich EVs in human urine samples and culture medium, enabling better isolation performance than conventional ultrafiltration. We believe the newly developed approach and insight gained in this study will facilitate the use of EVs as prominent biomaterials for disease diagnosis and therapy.
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2021
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Small extracellular vesicles in cancer
Extracellular vesicles (EV) are lipid-bilayer enclosed vesicles in submicron size that are released from cells. A variety of molecules, including proteins, DNA fragments, RNAs, lipids, and metabolites can be selectively encapsulated into EVs and delivered to nearby and distant recipient cells. In tumors, through such intercellular communication, EVs can regulate initiation, growth, metastasis and invasion of tumors. Recent studies have found that EVs exhibit specific expression patterns which mimic the parental cell, providing a fingerprint for early cancer diagnosis and prognosis as well as monitoring responses to treatment. Accordingly, various EV isolation and detection technologies have been developed for research and diagnostic purposes. Moreover, natural and engineered EVs have also been used as drug delivery nanocarriers, cancer vaccines, cell surface modulators, therapeutic agents and therapeutic targets. Overall, EVs are under intense investigation as they hold promise for pathophysiological and translational discoveries. This comprehensive review examines the latest EV research trends over the last five years, encompassing their roles in cancer pathophysiology, diagnostics and therapeutics. This review aims to examine the full spectrum of tumor-EV studies and provide a comprehensive foundation to enhance the field. The topics which are discussed and scrutinized in this review encompass isolation techniques and how these issues need to be overcome for EV-based diagnostics, EVs and their roles in cancer biology, biomarkers for diagnosis and monitoring, EVs as vaccines, therapeutic targets, and EVs as drug delivery systems. We will also examine the challenges involved in EV research and promote a framework for catalyzing scientific discovery and innovation for tumor-EV-focused research.
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2021
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Study On Plasma Exosome Biomarkers Of Pregnant Women With Intrahepatic Cholestasis of Pregnancy
Background:Elevated serum total bile acid level is currently the main index for clinical diagnosis of intrahepatic cholestasis of pregnancy, but the use of TBA as a detection index has certain limitations. The early diagnosis of ICP and new treatment options still need to be further strengthened. Methods: Plasma samples were collected, and exosomes were isolated. Key differential proteins were screened by bioinformatics methods. ELISA method was used to detect the concentration of the key differential protein cluster in plasma samples, and the ROC curve was drawn to find out the best critical value. Results: There were 138 differentially expressed proteins between the ICP group and the normal group by quantitative analysis. Cluster protein was screened as a clinical validation index. The cluster protein concentration of plasma exosomes in the ICP group was significantly higher than that in the normal group (P<0.0001). ROC curve analysis showed that the best critical point for diagnosing ICP according to the plasma exosome cluster protein concentration of pregnant women was 255.28 ng/ml. In the ICP group, the best crucial point for predicting ICP with premature delivery is 286.72 ng/ml. Conclusion: the plasma exosome cluster protein concentration of ICP pregnant women is significantly higher than that of normal pregnant women. When the plasma cluster protein concentration of pregnant women is more remarkable than 255.28ng/ml, ICP can be diagnosed. When the plasma cluster protein concentration of pregnant women is higher than 286.72ng/ml, ICP pregnant women are more likely to have a premature birth.
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2021
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Surfactant Protein B Promotes Cytosolic SiRNA Delivery by Adopting a Virus-like Mechanism of Action
RNA therapeutics are poised to revolutionize medicine. To unlock the full potential of RNA drugs, safe and efficient (nano)formulations to deliver them inside target cells are required. Endosomal sequestration of nanocarriers represents a major bottleneck in nucleic acid delivery. Gaining more detailed information on the intracellular behavior of RNA nanocarriers is crucial to rationally develop delivery systems with improved therapeutic efficiency. Surfactant protein B (SP-B) is a key component of pulmonary surfactant (PS), essential for mammalian breathing. In contrast to the general belief that PS should be regarded as a barrier for inhaled nanomedicines, we recently discovered the ability of SP-B to promote gene silencing by siRNA-loaded and lipid-coated nanogels. However, the mechanisms governing this process are poorly understood. The major objective of this work was to obtain mechanistic insights into the SP-B-mediated cellular delivery of siRNA. To this end, we combined siRNA knockdown experiments, confocal microscopy, and focused ion beam scanning electron microscopy imaging in an in vitro non-small-cell lung carcinoma model with lipid mixing assays on vesicles that mimic the composition of (intra)cellular membranes. Our work highlights a strong correlation between SP-B-mediated fusion with anionic endosomal membranes and cytosolic siRNA delivery, a mode of action resembling that of certain viruses and virus-derived cell-penetrating peptides. Building on these gained insights, we optimized the SP-B proteolipid composition, which dramatically improved delivery efficiency. Altogether, our work provides a mechanistic understanding of SP-B-induced perturbation of intracellular membranes, offering opportunities to fuel the rational design of SP-B-inspired RNA nanoformulations for inhalation therapy.
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2021
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TAF1 Transcripts and Neurofilament Light Chain as Biomarkers for X‐linked Dystonia‐Parkinsonism
Background X-linked dystonia-parkinsonism is a rare neurological disease endemic to the Philippines. Dystonic symptoms appear in males at the mean age of 40 years and progress to parkinsonism with degenerative pathology in the striatum. A retrotransposon inserted in intron 32 of the TAF1 gene leads to alternative splicing in the region and a reduction of the full-length mRNA transcript. Objectives The objective of this study was to discover cell-based and biofluid-based biomarkers for X-linked dystonia-parkinsonism. Methods RNA from patient-derived neural progenitor cells and their secreted extracellular vesicles were used to screen for dysregulation of TAF1 expression. Droplet-digital polymerase chain reaction was used to quantify the expression of TAF1 mRNA fragments 5′ and 3′ to the retrotransposon insertion and the disease-specific splice variant TAF1-32i in whole-blood RNA. Plasma levels of neurofilament light chain were measured using single-molecule array. Results In neural progenitor cells and their extracellular vesicles, we confirmed that the TAF1-3′/5′ ratio was lower in patient samples, whereas TAF1-32i expression is higher relative to controls. In whole-blood RNA, both TAF1-3′/5′ ratio and TAF1-32i expression can differentiate patient (n = 44) from control samples (n = 18) with high accuracy. Neurofilament light chain plasma levels were significantly elevated in patients (n = 43) compared with both carriers (n = 16) and controls (n = 21), with area under the curve of 0.79. Conclusions TAF1 dysregulation in blood serves as a disease-specific biomarker that could be used as a readout for monitoring therapies targeting TAF1 splicing. Neurofilament light chain could be used in monitoring neurodegeneration and disease progression in patients. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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2021
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The potential of exosome-based gene therapy to eradicate glioblastoma cells
New treatment methods are urgently needed for glioblastoma (GBM), the most common malignant primary brain tumor in adults, that currently lacks any curative treatment. Targeted therapeutic approaches have shown promising results already, but common drug delivery vehicles come with efficacy issues and are restricted by their safety and toxicity profiles. Exosomes, cell-produced nanosized vesicles, have emerged as a new potential carrier for gene therapies in cancer treatment due to their natural material transport properties, biocompatibility, and specificity in transporting cargo to the target cells. These extracellular vesicles have the additional advantage of being able to cross the blood-brain-barrier (BBB), which makes them especially valuable for brain malignancies, such as glioblastomas. So far, gene therapy approaches in exosomes have focused on RNA in cancer treatment, but research findings are limited with plasmid-based gene therapies using exosomes. The main concern has been whether the increased plasmid size would decrease the transfection efficiency of the plasmid into the exosomes. This study aimed at setting-up exosomes as plasmid-based gene therapy nanocarriers. To achieve this, different plasmid-based gene therapies were tested, including the targeting of common aberrations of GBM cells to impair proliferation and the use of cytotoxins to induce apoptosis in the target cells. The plasmids were transfected into exosomes and subsequently inoculated into patient-derived glioblastoma cells with the aim of decreasing the number of glioblastoma cells. The findings of this study demonstrate a successful set-up of an exosome-based gene therapy in patient-derived glioblastoma cells by using engineered HEK293FT cell derived exosomes consisting of a plasmid-based combination gene therapy encoding the cytotoxins Granzyme B and Diphtheria toxin fragment A.
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2021
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The Yin and Yang of exosome isolation methods: conventional practice, microfluidics, and commercial kits
Exosomes are a subset of extracellular vesicles released from various cells, and they can be found in different bodily fluids. Exosomes have been utilized as biomarkers to diagnose many diseases and to monitor therapy efficiency as they represent the status and origin of the cell, which they are released from. Considering that they co-exist in bodily fluids with other types of particles, their isolation still remains challenging since conventional methods are time-consuming, user-dependent, and result in low isolation yield. This review summarizes the conventional strategies and microfluidic-based methods for exosome isolation along with their strengths and limitations. In particular, microfluidic devices emerge as a promising approach to tackle the existing limitations of conventional methods, and they provide unique features, such as operating with minute volume of samples and rapid process, in order to isolate exosomes with the high yield and the high purity, which make them unprecedented tools for molecular biology and clinical applications in exosome research. This review further elaborates on the existing microfluidic-based exosome isolation methods and denotes their benefits and drawbacks. Herein, we also introduce various commercially available platforms and kits for exosome isolation along with their working principles.
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2021
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Tumor microenvironmental cytokines bound to cancer exosomes determine uptake by cytokine receptor-expressing cells and biodistribution
Metastatic spread of a cancer to secondary sites is a coordinated, non-random process. Cancer cell-secreted vesicles, especially exosomes, have recently been implicated in the guidance of metastatic dissemination, with specific surface composition determining some aspects of organ-specific localization. Nevertheless, whether the tumor microenvironment influences exosome biodistribution has yet to be investigated. Here, we show that microenvironmental cytokines, particularly CCL2, decorate cancer exosomes via binding to surface glycosaminoglycan side chains of proteoglycans, causing exosome accumulation in specific cell subsets and organs. Exosome retention results in changes in the immune landscape within these organs, coupled with a higher metastatic burden. Strikingly, CCL2-decorated exosomes are directed to a subset of cells that express the CCL2 receptor CCR2, demonstrating that exosome-bound cytokines are a crucial determinant of exosome-cell interactions. In addition to the finding that cytokine-conjugated exosomes are detected in the blood of cancer patients, we discovered that healthy subjects derived exosomes are also associated with cytokines. Although displaying a different profile from exosomes isolated from cancer patients, it further indicates that specific combinations of cytokines bound to exosomes could likewise affect other physiological and disease settings.
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2021
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A magnetic bead-mediated selective adsorption strategy for extracellular vesicle separation and purification
Extracellular vesicles (EVs) are membrane-encapsulated particles with critical biomedical functions, including mediating intercellular communication, assisting tumor metastasis, and carrying protein and microRNA biomarkers. The downstream applications of EVs are greatly influenced by the quality of the isolated EVs. However, almost none of the separation methods can simultaneously achieve both high yield and high purity of the isolated EVs, thus making the isolation of EVs an essential challenge in EV research. Here, we developed a magnetic bead-mediated selective adsorption strategy (MagExo) for easy-to-operate EV isolation. Benefited from the presence of an adsorption window between EVs and proteins under the effect of a hydrophilic polymer, EVs tend to adsorb on the surface of magnetic beads selectively and can be separated from biological fluids with high purity by simple magnetic separation. The proposed method was used for EV isolation from plasma and cell culture media (CCM), with two times higher yield and comparable purity of the harvested EVs to that obtained by ultracentrifugation (UC). Downstream applications in proteomics analysis showed 86.6% (plasma) and 86.5% (CCM) of the analyzed proteins were matched with the ExoCarta database, which indicates MagExo indeed enriches EVs efficiently. Furthermore, we found the target RNA amount of the isolated EVs by MagExo were almost dozens and hundred times higher than the gold standard DG-UC and ultracentrifugation (UC) methods, respectively. All the results show that MagExo is a reliable, easy, and efficient approach to harvest EVs for a wide variety of downstream applications with minimized sample usage. Statement of Significance Extracellular vesicles (EVs) are presently attracting increasing interest among clinical and scientific researchers. Although the downstream applications of EVs are recognized to be greatly affected by the quality of the isolated EVs, almost none of the separation methods can simultaneously achieve high yield and high purity of the isolated EVs; this makes the isolation of EVs an essential challenge in EV research. In the present work, we proposed a simple and easy-to-operate method (MagExo) for the separation and purification of EVs based on the phenomenon that EVs can be selectively adsorbed on the surface of magnetic microspheres in the presence of a hydrophilic polymer. The performance of MagExo was comparable to or even better than that of gold standard methods and commercial kits, with two times higher yield and comparable purity of the harvested EVs to that achieved with ultracentrifugation (UC); this could meet the requirements of various EV-associated downstream applications. In addition, MagExo can be easily automated by commercial liquid workstations, thus significantly improving the isolation throughput and paving a new way in clinical diagnosis and treatment.
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2021
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A new transgene mouse model using an extravesicular EGFP tag to elucidate the in vivo function of extracellular vesicles
The in vivo function of cell-derived extracellular vesicles (EVs) is challenging to establish since cell-specific EVs are difficult to isolate. We therefore created an EV reporter using CD9 to display enhanced green fluorescent protein (EGFP) on the EV surface. CD9-EGFP expression in cells did not affect EV size and concentration, but allowed for co-precipitation of EV markers TSG101 and ALIX from cell-conditioned medium by anti-GFP immunoprecipitation. We created a transgenic mouse where CD9-EGFP was inserted in the inverse orientation and double-floxed, ensuring Cre recombinase-dependent EV reporter expression. We crossed the EV reporter mice with mice expressing Cre ubiquitously (CMV- Cre), in cardiomyocytes (AMHC-Cre) and kidney epithelium (Pax8-Cre), respectively. The mice showed tissue-specific EGFP expression, and plasma and urine samples were used to immunoprecipitate EVs. CD9-EGFP EVs was detected in plasma samples from CMV-Cre/CD9-EGFP and AMHC-Cre/CD9-EGFP mice, but not in PAX8-Cre/CD9-EGFP mice. On the other hand, CD9-EGFP EVs were detected in urine samples from CMV-Cre/CD9-EGFP and PAX8-Cre/CD9-EGFP mice, but not AMHC-Cre/CD9-EGFP, indicating that plasma EVs are not filtered to the urine. In conclusion, our EV reporter mouse model enables Cre-dependent EV labeling, providing a new approach to study cell-specific EVs in vivo and gain new insight into their physiological and pathophysiological function.
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2021
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A novel protein signature from plasma extracellular vesicles for non-invasive differential diagnosis of idiopathic pulmonary fibrosis
Background Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia of unknown etiology often leading to respiratory failure. Over half of IPF patients present with discordant features of usual interstitial pneumonia on high-resolution computed tomography at diagnosis which warrants surgical lung biopsy to exclude the possibility of other interstitial lung diseases (ILDs). Therefore, there is a need for non-invasive biomarkers for expediting the differential diagnosis of IPF. Methods Using mass spectrometry, we performed proteomic analysis of plasma extracellular vesicles (EVs) in a cohort of subjects with IPF, chronic hypersensitivity pneumonitis, nonspecific interstitial pneumonitis, and healthy subjects (HS). A five-protein signature was identified by lasso regression and was validated in an independent cohort using ELISA. We evaluated the concordance between plasma EV proteome and the lung transcriptome data. Lastly, we compared the molecular pathways overrepresented in IPF by differentially expressed proteins and transcripts from EVs and lung tissues, respectively. Results The five-protein signature derived from mass spectrometry data showed area under the receiver operating characteristic curve of 0.915 (95%CI: 0.819-1.011) and 0.958 (95%CI: 0.882-1.034) for differentiating IPF from other ILDs and from HS, respectively. We also found that the EV protein expression profiles mirrored their corresponding mRNA expressions in IPF lungs. Further, we observed an overlap in the EV proteome- and lung mRNA-associated molecular pathways. Conclusions We discovered a plasma EV-based protein signature for differential diagnosis of IPF and validated this signature in an independent cohort. The signature needs to be tested in large prospective cohorts to establish its clinical utility. Competing Interest Statement AKP is employed with Izon Science US Ltd. The company has no role in design of the study and acquisition of experimental data and interpretation. All other authors have no conflict of interests. Funding Statement This work was supported by UT System Rising STARs award and core funds from UTHSCT, Tyler, Texas, to NVK. DN received funding from NIH (R01 GM083122). Cryo-TEM is supported by Cancer Prevention and Research Institute of Texas grant RR140082 to DN. Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study was approved by institutional review boards of University of Pittsburgh (IRB STUDY19040326 and STUDY20030223), Brigham and Womens hospital (IRB2012P000840), Hiroshima University (IRBM326) and University of Texas Health Science Center at Tyler (IRB 20-019 & 0000370). All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes
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2021
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A perspective on the isolation and characterization of extracellular vesicles from different biofluids
Extracellular vesicles (EVs) are small membrane-bound particles, which include exosomes, micro vesicles (MVs) and various-sized vesicles, released by healthy and diseased cells. EVs also include other vesicular structures, such as large apoptotic bodies (1–5 μm), as well as membrane particles (50–80 nm) originating from the plasma membrane. However, exosomes are nanosize (≈30–100 nm) extracellular vesicles of endocytic origin that are bud-off by most types of cells and circulate in bodily fluids. Extracellular nanovesicles contain a large variety of biomolecules, including miRNA, RNA, DNA, proteins, signaling peptides and lipids, that can have diagnostic and therapeutic value. The spectrum of the existing scientific interest in extracellular nanovesicles is comprehensive, which ranges from understanding their functions and pathways to their potential clinical usage. EVs can be obtained from different body fluids with minimally invasive techniques (e.g., urine, plasma, serum), so they are most useful in disease diagnosis. High yield and purity contribute to the accurate diagnosis of various diseases, but damaged EVs and impurities can cause misinterpreted results. Over the last decade, a plethora of approaches have been developed for examining EVs using optical and non-optical tools. However, EV isolation methods have different yields and purities. Moreover, the isolation method that is most appropriate to maximize EVs recovery depends on the different experimental situations. This review explores the emerging use of micro and nano-technologies to isolate and characterize exosomes and microvesicles (MVs) from different biological samples, and the application of these technologies for the monitoring and diagnosis of different pathological conditions.
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2021
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A simple displacement aptamer assay on resistive pulse sensor for small molecule detection
A universal aptamer-based sensing strategy is proposed using DNA modified nanocarriers and Resistive Pulse Sensing (RPS) for the rapid (≤20 min) and label free detection of small molecules. The surface of a magnetic nanocarrier was first modified with a ssDNA (anchor) which is designed to be partially complimentary in sequence to the ssDNA aptamer. The aptamer and anchor form a stable dsDNA complex on the nanocarriers surface. Upon the addition of the target molecule, a conformational change takes place where the aptamer preferentially binds to the target over the anchor; causing the aptamer to be released into solution. The RPS measures the change in velocity of the nanocarrier as its surface changes from dsDNA to ssDNA, and its velocity is used as a proxy for the concentration of the target. The length of the aptamer and the ability to extract and preconcentrate the nanocarriers using a magnet, is shown to affect the sensitivity. We illustrate the versatility of the assay using the same anchor sequence and Aptamers to the antibiotic Moxifloxacin, and chemotherapeutics Imatinib and Irinotecan. In addition, the proposed assay can be easily extended to detect multiple analytes simultaneously, by utilizing nanocarriers with different diameters. Each sized particle is functionalised with a the same anchor but a unique aptamer. We illustrate this with the simultaneous detection of Imatinib and Moxifloxacin. The strategy could be easily adapted to a range of targets and unlike previous strategies that use aptamer modified nanocarriers, the signal is not dependent upon the tertiary structure of the aptamer-target interaction.
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2021
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Aberrant Membrane Structures in Hypervesiculating Escherichia coli Strain ΔmlaEΔnlpI Visualized by Electron Microscopy
Escherichia coli produces extracellular vesicles called outer membrane vesicles (OMVs) by releasing a part of its outer membrane. We previously reported that the combined deletion of nlpI and mlaE, related to envelope structure and phospholipid accumulation in the outer leaflet of the outer membrane, respectively, resulted in the synergistic increase of OMV production. In this study, the analysis of ΔmlaEΔnlpI cells using quick-freeze, deep-etch electron microscopy (QFDE-EM) revealed that plasmolysis occurred at the tip of the long axis in cells and that OMVs formed from this tip. Plasmolysis was also observed in the single-gene knockout mutants ΔnlpI and ΔmlaE. This study has demonstrated that plasmolysis was induced in the hypervesiculating mutant E. coli cells. Furthermore, intracellular vesicles and multilamellar OMV were observed in the ΔmlaEΔnlpI cells. Meanwhile, the secretion of recombinant green fluorescent protein (GFP) expressed in the cytosol of the ΔmlaEΔnlpI cells was more than 100 times higher than that of WT and ΔnlpI, and about 50 times higher than that of ΔmlaE in the OMV fraction, suggesting that cytosolic components were incorporated into outer-inner membrane vesicles (OIMVs) and released into the extracellular space. Additionally, QFDE-EM analysis revealed that ΔmlaEΔnlpI sacculi contained many holes noticeably larger than the mean radius of the peptidoglycan (PG) pores in wild-type (WT) E. coli. These results suggest that in ΔmlaEΔnlpI cells, cytoplasmic membrane materials protrude into the periplasmic space through the peptidoglycan holes and are released as OIMVs.
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2021
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An integrated workflow for biomarker development using microRNAs in extracellular vesicles for cancer precision medicine
EV-miRNAs are microRNA (miRNA) molecules encapsulated in extracellular vesicles (EVs), which play crucial roles in tumor pathogenesis, progression, and metastasis. Recent studies about EV-miRNAs have gained novel insights into cancer biology and have demonstrated a great potential to develop novel liquid biopsy assays for various applications. Notably, compared to conventional liquid biomarkers, EV-miRNAs are more advantageous in representing host-cell molecular architecture and exhibiting higher stability and specificity. Despite various available techniques for EV-miRNA separation, concentration, profiling, and data analysis, a standardized approach for EV-miRNA biomarker development is yet lacking. In this review, we performed a substantial literature review and distilled an integrated workflow encompassing important steps for EV-miRNA biomarker development, including sample collection and EV isolation, EV-miRNA extraction and quantification, high-throughput data preprocessing, biomarker prioritization and model construction, functional analysis, as well as validation. With the rapid growth of “big data”, we highlight the importance of efficient mining of high-throughput data for the discovery of EV-miRNA biomarkers and integrating multiple independent datasets for in silico and experimental validations to increase the robustness and reproducibility. Furthermore, as an efficient strategy in systems biology, network inference provides insights into the regulatory mechanisms and can be used to select functionally important EV-miRNAs to refine the biomarker candidates. Despite the encouraging development in the field, a number of challenges still hinder the clinical translation. We finally summarize several common challenges in various biomarker studies and discuss potential opportunities emerging in the related fields.
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2021
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An SPRi-based biosensor pilot study: Analysis of multiple circulating extracellular vesicles and hippocampal volume in Alzheimer's disease
One of the main hurdles in the study of Alzheimer’s Disease (AD) is the lack of easily accessible and sensitive biomarkers for the diagnosis, the prediction of the disease progression rate and the evaluation of rehabilitative and pharmacological treatments. Extracellular Vesicles (EVs) are nanoscale particles released by body cells, studied as promising biomarkers of AD as they are involved in the onset and progression of the disease. In the strive for a reliable and sensitive method to analyze EVs, we applied our recently developed biosensor based on Surface Plasmon Resonance imaging (SPRi) technology for the identification and profiling of neural EVs populations circulating in the plasma of 10 AD patients and 10 healthy subjects. The SPRi-array was designed to separate simultaneously EVs released by neurons, astrocytes, microglia and oligodendrocytes, and to evaluate the presence and the relative amount of specific surface molecules related to pathological processes including translocator protein (TSPO), β-Amyloid and ganglioside M1. As results, significant variations in the relative amount and cargoes of specific brain-derived populations of EVs were observed comparing EVs coming from AD patients and healthy subjects, finding the main differences in the activation phenotype of microglia EVs, in the lipid moieties on generic EVs and in the β-Amyloid expression on surfaces of neuronal EVs. Besides, the demonstrated correlation of SPRi data with Magnetic Resonance Imaging analysis, provided support for using the SPRi-based biosensor for the evaluation of neurodegeneration detecting and characterizing circulating EVs as peripheral biomarkers for the diagnosis and monitoring of progression and rehabilitation treatments in AD patients.
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2021
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Analysis of extracellular vesicles as a potential index for monitoring differentiation of neural lineage cells from induced pluripotent stem cells
To improve cell production efficacy, it is important to evaluate cell conditions during culture. Extracellular vesicles (EVs) secreted from various cells are involved in stem cell differentiation. As EVs carry information about their source cells, we hypothesized that they may serve as a noninvasive index of cell conditions. We evaluated changes in EV morphology, concentration, and microRNA (miRNA) and protein expression in culture supernatants during the differentiation of induced pluripotent stem cells (iPSCs) into neural lineage cells, for application in regenerative medicine for Parkinson's disease. We observed EVs (50–150 nm) in culture supernatants of iPSCs and differentiated cells. The EVs expressed the exosome markers CD63, CD81, and CD9. Throughout differentiation, the EV concentration in the supernatants decreased, and EV miRNA and protein expression changed substantially. Especially, miR-106b, involved in neural stem cell differentiation and normal brain development, was considerably downregulated. CD63 expression correlated with the CORIN-positive cell rate, which is an index of differentiation. Thus, EV concentration and miRNA and protein expression may reflect the differentiation status of iPSCs. These findings pave the way for the development of novel and sensitive cell culture monitoring methods.
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2021
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Analyzing Inter-Leukocyte Communication and Migration In Vitro: Neutrophils Play an Essential Role in Monocyte Activation During Swarming
Neutrophils are known to be the first responders to infection or injury. However, as inflammation progresses, other leukocytes become increasingly important in inflammation propagation, tissue reconstruction, and inflammation resolution. In recent years, there has been an increase in publications that analyze neutrophil behavior in vitro, but there remains a gap in the literature for in vitro technologies that enable quantitatively measuring interactions between different types of human leukocytes. Here, we used an in vitro platform that mimics inflammation by inducing neutrophil swarming to analyze the behavior of various leukocytes in a swarming setting. Using human peripheral blood leukocytes isolated directly from whole blood, we found that myeloid cells and lymphoid cells had different migratory behaviors. Myeloid cells, which are predominately neutrophils, exhibited swarming behavior. This behavior was not seen with lymphoid cells. We perturbed the peripheral blood leukocyte system by adding exogenous leukotriene B4 (LTB4) to the medium. Notably, only the myeloid cell compartment was significantly changed by the addition of LTB4. Additionally, LTB4 had no significant impact on myeloid cell migration during the recruitment phase of swarming. To further investigate the myeloid cell compartment, we isolated neutrophils and monocytes to analyze their interaction on the platform. We found that neutrophils increase monocyte migration toward the bioparticle clusters, as measured through speed, chemotactic index, track straightness, and swarm size. These results were confirmed with in vivo mouse experiments, where monocyte accumulation only occurred when neutrophils were present. Additionally, we found that both neutrophils and monocytes release the monocyte chemoattractant proteins CCL2 and CCL3 in the presence of Staphylococcus aureus bioparticles. Furthermore, extracellular vesicles from swarming neutrophils caused monocyte activation. These findings suggest that neutrophils play an essential role in the onset of inflammation not only by sealing off the site of infection or injury, but also by recruiting additional leukocytes to the site.
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2021
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Antioxidative Effects of Carrot-Derived Nanovesicles in Cardiomyoblast and Neuroblastoma Cells
Oxidative stress is implicated in many diseases, including cardiovascular and neurodegenerative diseases. Because an increased level of oxidative stress causes apoptosis, it is necessary to inhibit cellular responses to oxidative stress. In this study, Carex, a nanovesicle from carrot, was isolated and investigated as a novel biomaterial with antioxidative function in cardiomyoblasts and neuroblastoma cells. A high concentration of nanovesicles was purified from carrots, using size-exclusion chromatography in combination with ultrafiltration. The characterization of Carex demonstrated that it had properties similar to those of extracellular vesicles. Carex showed low cytotoxicity in both H9C2 cardiomyoblasts and SH-SY5Y neuroblastoma cells, when a high level of Carex was delivered to the cells. Carex was further investigated for its antioxidative and apoptotic effects, and it significantly inhibited ROS generation and apoptosis in vitro in myocardial infarction and Parkinson’s disease models. Carex inhibited the reduction of antioxidative molecule expression, including Nrf-2, HO-1, and NQO-1, in both models. Considering its antioxidative function and high production yield, Carex is a potential drug candidate for the treatment of myocardial infarction as well as Parkinson’s disease. Thus, the results demonstrated in this study will contribute to an exploration of a novel drug, using nanovesicles from plants, including carrots.
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2021
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Applications of cell resealing to reconstitute microRNA loading to extracellular vesicles
MicroRNAs (miRNAs) are cargo carried by extracellular vesicles (EVs) and are associated with cell–cell interactions. The response to the cellular environment, such as disease states, genetic/metabolic changes, or differences in cell type, highly regulates cargo sorting to EVs. However, morphological features during EV formation and secretion involving miRNA loading are unknown. This study developed a new method of EV loading using cell resealing and reconstituted the elementary miRNA-loading processes. Morphology, secretory response, and cellular uptake ability of EVs obtained from intact and resealed HeLa cells were comparable. Exogenously added soluble factors were introduced into multivesicular endosomes (MVEs) and their subsequent secretion to the extracellular region occurred in resealed HeLa cells. In addition, miRNA transport to MVEs and miRNA encapsulation to EVs followed a distinct pathway regulated by RNA-binding proteins, such as Argonaute and Y-box binding protein 1, depending on miRNA types. Our cell-resealing system can analyze disease-specific EVs derived from disease model cells, where pathological cytosol is introduced into cells. Thus, EV formation in resealed cells can be used not only to create a reconstitution system to give mechanistic insight into EV encapsulation but also for applications such as loading various molecules into EVs and identifying disease-specific EV markers.
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2021
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Assembly and Entry of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2): Evaluation Using Virus-Like Particles
Research on infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is currently restricted to BSL-3 laboratories. SARS-CoV2 virus-like particles (VLPs) offer a BSL-1, replication-incompetent system that can be used to evaluate virus assembly and virus-cell entry processes in tractable cell culture conditions. Here, we describe a SARS-CoV2 VLP system that utilizes nanoluciferase (Nluc) fragment complementation to track assembly and entry. We utilized the system in two ways. Firstly, we investigated the requirements for VLP assembly. VLPs were produced by concomitant synthesis of three viral membrane proteins, spike (S), envelope (E), and matrix (M), along with the cytoplasmic nucleocapsid (N). We discovered that VLP production and secretion were highly dependent on N proteins. N proteins from related betacoronaviruses variably substituted for the homologous SARS-CoV2 N, and chimeric betacoronavirus N proteins effectively supported VLP production if they contained SARS-CoV2 N carboxy-terminal domains (CTD). This established the CTDs as critical features of virus particle assembly. Secondly, we utilized the system by investigating virus-cell entry. VLPs were produced with Nluc peptide fragments appended to E, M, or N proteins, with each subsequently inoculated into target cells expressing complementary Nluc fragments. Complementation into functional Nluc was used to assess virus-cell entry. We discovered that each of the VLPs were effective at monitoring virus-cell entry, to various extents, in ways that depended on host cell susceptibility factors. Overall, we have developed and utilized a VLP system that has proven useful in identifying SARS-CoV2 assembly and entry features.
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2021
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Bioinspired artificial exosomes based on lipid nanoparticles carrying let-7b-5p promote angiogenesis in vitro and in vivo
MicroRNAs (miRNAs) regulate gene expression by post-transcriptional inhibition of target genes. Proangiogenic small extracellular vesicles (sEVs; popularly identified with the name “exosomes”) with a composite cargo of miRNAs are secreted by cultured stem cells and present in human biological fluids. Lipid nanoparticles (LNPs) represent an advanced platform for clinically approved delivery of RNA therapeutics. In this study, we aimed to (1) identify the miRNAs responsible for sEV-induced angiogenesis; (2) develop the prototype of bioinspired “artificial exosomes” (AEs) combining LNPs with a proangiogenic miRNA, and (3) validate the angiogenic potential of the bioinspired AEs. We previously reported that human sEVs from bone marrow (BM)-CD34+ cells and pericardial fluid (PF) are proangiogenic. Here, we have shown that sEVs secreted from saphenous vein pericytes and BM mesenchymal stem cells also promote angiogenesis. Analysis of miRNA datasets available in-house or datamined from GEO identified the let-7 family as common miRNA signature of the proangiogenic sEVs. LNPs with either hsa-let-7b-5p or cyanine 5 (Cy5)-conjugated Caenorhabditis elegans miR-39 (Cy5-cel-miR-39; control miRNA) were prepared using microfluidic micromixing. let-7b-5p-AEs did not cause toxicity and transferred functionally active let-7b-5p to recipient endothelial cells (ECs). let-7b-AEs also improved EC survival under hypoxia and angiogenesis in vitro and in vivo. Bioinspired proangiogenic AEs could be further developed into innovative nanomedicine products targeting ischemic diseases.
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2021
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Biophysical and Computational Studies of Human Disease Related Proteins with a Single-Pass Transmembrane Helix
Single-pass transmembrane receptors (SPTMRs) are involved in essential processes of biophysical and pathological nature in the human. This membrane protein family includes receptor tyrosine kinases, integrins, and immunoreceptors, which play an important role in metabolism, growth, proliferation, and apoptosis. SPTMR consists of several distinct domains including the extracellular domain (ECD), the transmembrane domain (TMD), and the intracellular domain (ICD) and exists as a monomer, homo- and/or heterodimer. Upon a ligand ligation through ECD, homo- or heterodimerization of SPTMR forms, followed by consequent modification of the ICDs, leading to the initiation of cellular signaling events. This activation requires interactions between TMD helices whose role in receptor activation becomes important. TMD is further highlighted by the discovery of mutations in the TMD or juxtamembrane domain (JMD) that are associated with human diseases. However, the details of cross-membrane signal transduction via SPTMRs have to be elucidated. Due to the high conformational flexibility of SPTMRs with their diverse structural composition, it is hard to characterize SPTMRs structurally. This drives us to work with only TMD helices of SPTMRs and focus on their interactions in the lipid bilayer environment. Our approach is the use of not only experimental data but also computational MD simulations to understand how TMD helices interact and how mutants associated with diseases affect the dimerization of TMD helices.
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2021
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Bone marrow mesenchymal stem cell derived exosomes delay the occurrence and development of osteoarthritis through cartilage protection
Osteoarthritis is the most common joint degenerative disease. At present, bone marrow mesenchymal stem cells have been used in the treatment of osteoarthritis. However, compared with bone marrow mesenchymal stem cells, bone marrow mesenchymal stem cell derived exosome transplantation has more advantages, such as non-immunogenicity, non-tumorigenicity, convenient storage and transportation. OBJECTIVE: To explore the protective effect of bone marrow mesenchymal stem cell exosomes on osteoarthritis.  METHODS: (1) SD rat bone marrow mesenchymal stem cells were extracted and identified by cell morphology and flow cytometry. Exosomes in the cell supernatant were extracted by ultracentrifugation and identified by transmission electron microscopy, particle size and western blot assay. (2) Primary costal chondrocytes were extracted from suckling rats and cocultured with fluorescently labeled exosomes for 12 hours. The phagocytosis of chondrocytes was observed. In vitro chondrocyte damage was induced by interleukin-1β. PBS (100 μL) containing 50 μg exosomes was added for 24 hours. The expression of matrix metalloproteinase-13 and type II collagen fiber α1 protein was detected by immunofluorescence to evaluate the protective effect of exosomes on injured chondrocytes. (3) The rat model of osteoarthritis was induced by iodoacetic acid in vivo. Exosomes were injected into the joint cavity, and the changes of joint structure of osteoarthritis were observed by hematoxylin-eosin staining and safrane-fast green staining. The expression of matrix metalloproteinase-13 and type II collagen fiber α1 protein was measured by immunohistochemical staining to evaluate the protective effect of exosomes on cartilage in vivo.  RESULTS AND CONCLUSION: (1) The extracted primary cells showed a typical fusiform shape and arranged radially. The extracted cells highly expressed CD73 and CD105, but slightly expressed CD45, CD34 and CD3. Transmission electron microscopy showed that the obtained particles showed a typical saucer-like morphology. The particle size was less than 100 nm. Meanwhile, nanoparticles showed positive expression of ALIX and HRS protein. (2) Typical red-stained particles could be observed in chondrocytes, which confirms that exosomes could be taken up by chondrocytes, and exosomes could promote chondrocyte type II collagen fiber α1 protein expression, but inhibit the expression of matrix metalloproteinase-13, which confirmed that exosomes could attenuate the damage effect of interleukin-1β on chondrocytes. (3) Exosomes could promote the morphological recovery of damaged articular cartilage and the up-regulate type II collagen fiber α1 expression, while inhibited the expression of matrix metalloproteinase-13, which also confirmed that exosomes can alleviate the effects of iodoacetic acid on articular cartilage damage. (4) Above findings results indicate that bone marrow mesenchymal stem cell exosomes delay the occurrence and development of osteoarthritis through a chondroprotective mechanism.
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2021
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Bone Marrow Mesenchymal Stem Cells-Derived Extracellular Vesicles Promote Proliferation, Invasion and Migration of Osteosarcoma Cells via the lncRNA MALAT1/miR-143/NRSN2/Wnt/β-Catenin Axis
Introduction Osteosarcoma is a malignant primary bone tumor. Bone marrow-derived mesenchymal stem cells-derived extracellular vesicles (BMSC-EVs) bear repair function for bone and cartilage. This study investigated the mechanism of BMSC-EVs in osteosarcoma cell proliferation, migration and invasion. Methods BMSC-EVs were isolated and identified. The effects of different concentrations of EVs on osteosarcoma cell proliferation, migration and invasion were evaluated. LncRNA MALAT1 expression in osteosarcoma cells was detected. BMSCs were transfected with si-MALAT1 or si-NC. The binding relationships between MALAT1 and miR-143, and miR-143 and NRSN2 were verified. Levels of NRSN2 and Wnt/β-catenin pathway key proteins were detected. miR-143 mimic was transfected into EVs-treated osteosarcoma cells. Nude mice were injected with MG63 cells to verify the effect of EVs on osteosarcoma growth in vivo. Results BMSC-EVs facilitated proliferation, invasion and migration of osteosarcoma cells. BMSC-EVs carried MALAT1 into osteosarcoma cells. BMSC-EVs-treated osteosarcoma cells showed increased MALAT1 and NRSN2 expressions, decreased miR-143 expression, and activated Wnt/β-catenin pathway. miR-143 mimic or si-MALAT1 reversed the effects of BMSC-EVs on osteosarcoma cells. In vivo experiment confirmed that BMSC-EVs promoted tumor growth in nude mice. Discussion BMSC-EVs promoted proliferation, invasion and migration of osteosarcoma cells via the MALAT1/miR-143/NRSN2/Wnt/β-catenin axis. This study might offer new insights into osteosarcoma management. Keywords: osteosarcoma, bone marrow-derived mesenchymal stem cells, extracellular vesicles, lncRNA MALAT1, miR-143, NRSN2, Wnt/β-catenin pathway
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2021
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Cancer-Associated Fibroblasts Exosomal miR-106a Promotes Breast Cancer Invasion and Metastasis by Down-regulation of TCEAL7
Studies have shown that cancer-associated broblasts (CAFs) play an irreplaceable role in the occurrence and development of tumors. Therefore, exploring the action and mechanism of CAFs on tumor cells is particularly important for designing new and effective treatments and improving prognosis of tumors. For exosomes have been shown to play vital roles in intercellular communication, in this study, we compared the effects of CAFs-derived exosomes and NFs-derived exosomes on breast cancer cell proliferation, migration, and metastasis. The results showed that exosomes from both CAFs and NFs could enter into breast cancer cells and CAFs-derived exosomes had a more enhancing effect on breast cancer cell proliferation and invasion than NFs-derived exosomes. Furthermore, it was found that the expression levels of miR-106a in exosomes derived from CAFs were signicantly up-regulated than that of NFsderived exosomes and what’s more, in vitro and in vivo studies have shown that miR-106a can promote breast cancer cell proliferation, migration and metastasis by specically binding to the 3'UTR of TCEAL7. It is inspiring to nd that the miR-106a-TCEAL7 pathway promotes Snail nuclear ectopic activation by activating NF-κB, thereby inducing epithelial-mesenchymal transition and promoting cell proliferation and metastasis. Moreover, a mouse xenograft model conrmed that CAFs-derived exosomes miR-106a could promote tumor metastasis. The above data shows that CAFs-derived exosomes miR-106a promote Snail nuclear ectopic by targeting TCEAL7 to activate the NF-κB pathway, thereby inducing EMT, invasion and metastasis of breast cancer. Targeting CAFs-derived exosome miR-106a may be a potential treatment option to overcome breast cancer progression.
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2021
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Caracterización de partículas coloidales en el agua del suelo mediante detección sintonizable de pulsos resistivos
The transport of colloids in soil determines the fate of pollutants, nutrients and microorganisms in the environment and the contamination of groundwater. Colloidal retention mechanisms in soils depend on complex interactions between the soil pore walls and colloids. The hypothesis of this thesis is that the interaction of the particulate colloidal pollutants with the colloids present in the soil pore water has a dramatic influence on the transport of pollutants. This is due to the fact that the filtration of colloids in the porous medium depends on the size, shape and charge of the coatings and colloidal aggregates formed between the polluting particles and the suspended soil colloids. Improving the characterization of colloidal particulate pollutants in soil water can help to explain more precisely the role of soil as a filter for pollutants. Emerging technologies in particle characterization can represent an important advance in this characterization. Specifically, the tunable resistive pulse sensing (TRPS) detection technology allows the real (non-hydrodynamic) size of individual particles to be determined with high precision in a polydisperse suspension between 40 nm and 3 micrometers, in addition to determining, also individually, their surface electrical potential. The new knowledge that this technique can provide could lead to a better understanding of the transport of particulate pollutants in the soil, which could improve the diagnosis of potential vulnerability of subsurface waters against pathogenic organisms, engineered nanoparticles and metals bound to colloids, as well as optimize the design of micro and nanopesticide formulations.
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2021
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Cardioprotection by remote ischemic conditioning is transferable by plasma and mediated by extracellular vesicles
Background Remote ischemic conditioning (RIC) by brief periods of limb ischemia and reperfusion protects against ischemia–reperfusion injury. We studied the cardioprotective role of extracellular vesicles (EV)s released into the circulation after RIC and EV accumulation in injured myocardium. Methods We used plasma from healthy human volunteers before and after RIC (pre-PLA and post-PLA) to evaluate the transferability of RIC. Pre- and post-RIC plasma samples were separated into an EV enriched fraction (pre-EV + and post-EV +) and an EV poor fraction (pre-EV- and post-EV-) by size exclusion chromatography. Small non-coding RNAs from pre-EV + and post-EV + were purified and profiled by NanoString Technology. Infarct size was compared in Sprague–Dawley rat hearts perfused with isolated plasma and fractions in a Langendorff model. In addition, fluorescently labeled EVs were used to assess homing in an in vivo rat model. (ClinicalTrials.gov, number: NCT03380663) Results Post-PLA reduced infarct size by 15% points compared with Pre-PLA (55 ± 4% (n = 7) vs 70 ± 6% (n = 8), p = 0.03). Post-EV + reduced infarct size by 16% points compared with pre-EV + (53 ± 15% (n = 13) vs 68 ± 12% (n = 14), p = 0.03). Post-EV- did not affect infarct size compared to pre-EV- (64 ± 3% (n = 15) and 68 ± 10% (n = 16), p > 0.99). Three miRNAs (miR-16-5p, miR-144-3p and miR-451a) that target the mTOR pathway were significantly up-regulated in the post-EV + group. Labelled EVs accumulated more intensely in the infarct area than in sham hearts. Conclusion Cardioprotection by RIC can be mediated by circulating EVs that accumulate in injured myocardium. The underlying mechanism involves modulation of EV miRNA that may promote cell survival during reperfusion.
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2021
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Characterisation of extracellular vesicles in the context of myocardial infarction and glucose intolerance
Introduction In response to myocardial infarction (MI), extracellular vesicles (EVs), including large (lEVs) and small (sEVs), are released within and from the heart to facilitate intercellular communication and maintain cardiac homeostasis by transporting cargo to recipient cells. Objective We investigated how glucose intolerance influences the intracardiac EV release post-MI and their content. Method B6J mice were fed chow (CD) or high-fat diet (HFD) for 3 months. MI was induced by permanent coronary artery ligation. EVs were isolated from left ventricles and quantified by tunable resistive pulse sensing. EVs were characterised by flow cytometry. EV miRNA content was determined by RNAseq and qPCR. Using cardiomyocyte specific GFP+ mice, plasma lEVs were analysed by flow cytometry to determine if cardiomyocyte EVs (CMEVs) are circulating. Labelled hypoxic cardiomyocyte cell line (HL-1) lEVs were injected in HFD/CD mice post-MI to determine target cells. Results In CD mice, EV release was significantly increased 24 h post-MI compared to sham. HFD lEV levels were significantly higher compared to sham and CD mice post-MI with no difference in sEV release between sham and MI HFD mice. Intracardiac lEVs originate from cardiomyocyte and endothelial cells in response to MI and MI + HFD respectively. qPCR analyses identified miRNA candidates that were modulated by MI and HFD. Intracardiac GFP + lEV levels were lower in HFD than in CD mice whereas levels of circulating GFP + lEVs were higher. In vivo biodistribution studies revealed a preferential uptake of hypoxic HL-1 lEVs by splenic myeloid cells in HFD spleens versus CD post-MI. Conclusion Our results show that glucose intolerance modulates intracardiac EV release post-MI and their miRNA cargo. Circulating CMEV levels as well as their uptake by splenic myeloid cells are increased. Further investigations will aim to decipher the impact of the intracardiac EV miRNA mediated transfer in the diabetic heart post-MI.
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2021
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Characterization of extracellular vesicles and synthetic nanoparticles with four orthogonal single‐particle analysis platforms
We compared four orthogonal technologies for sizing, counting, and phenotyping of extracellular vesicles (EVs) and synthetic particles. The platforms were: single-particle interferometric reflectance imaging sensing (SP-IRIS) with fluorescence, nanoparticle tracking analysis (NTA) with fluorescence, microfluidic resistive pulse sensing (MRPS), and nanoflow cytometry measurement (NFCM). EVs from the human T lymphocyte line H9 (high CD81, low CD63) and the promonocytic line U937 (low CD81, high CD63) were separated from culture conditioned medium (CCM) by differential ultracentrifugation (dUC) or a combination of ultrafiltration (UF) and size exclusion chromatography (SEC) and characterized by transmission electron microscopy (TEM) and Western blot (WB). Mixtures of synthetic particles (silica and polystyrene spheres) with known sizes and/or concentrations were also tested. MRPS and NFCM returned similar particle counts, while NTA detected counts approximately one order of magnitude lower for EVs, but not for synthetic particles. SP-IRIS events could not be used to estimate particle concentrations. For sizing, SP-IRIS, MRPS, and NFCM returned similar size profiles, with smaller sizes predominating (per power law distribution), but with sensitivity typically dropping off below diameters of 60 nm. NTA detected a population of particles with a mode diameter greater than 100 nm. Additionally, SP-IRIS, MRPS, and NFCM were able to identify at least three of four distinct size populations in a mixture of silica or polystyrene nanoparticles. Finally, for tetraspanin phenotyping, the SP-IRIS platform in fluorescence mode was able to detect at least two markers on the same particle, while NFCM detected either CD81 or CD63. Based on the results of this study, we can draw conclusions about existing single-particle analysis capabilities that may be useful for EV biomarker development and mechanistic studies.
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2021
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Characterization of feces-derived bacterial membrane vesicles and the impact of their origin on the inflammatory response
The human gastrointestinal tract harbors a diverse and complex microbiome, which interacts in a variety of ways with the host. There is compelling evidence that gut microbial dysbiosis, defined as an alteration of diversity and abundance in intestinal microbes, is an etiological factor in inflammatory bowel disease (IBD). Membrane vesicles (MVs), which are nano-sized particles released by bacteria, have been found to interact with the host and modulate the development and function of the immune system. As a result MVs have been suggested to play a critical role in both health and disease. In this study we developed a method to isolate, characterize and assess the immunoreactivity of heterogeneous populations of MVs from fecal samples (fMVs) of healthy volunteers. We successfully isolated 2*109-2*1010 particles/ml from 0.5 gram of feces by using a combination of ultrafiltration and size exclusion chromatography (SEC) from 10 fecal samples. Bead-based flowcytometry in combination with tunable resistive pulse sensing (TRPS) provided a reliable method for (semi-)quantitative determination of fMVs originating from both Gram-positive and Gram-negative bacteria, while transmission electron microscopy confirmed the presence of fMVs. Real time 16s PCR on bacterial cell fractions or isolated fMVs DNA of the most common phyla (Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria) revealed differences in the relative abundance between bacteria and the fMVs. Moreover, fMVs evoke the release of TNF- by THP-1 cells in a dose-dependent matter. Also, a significant positive correlation was found between Actinobacteria/-Proteobacteria derived vesicles and the release of TNF-. It has become increasingly clear that fMVs could provide an additional layer to the definition of homeostasis or dysbiosis of the microbiota. The current study supports their potential involvement in the intestinal homeostasis or inflammatory disorders and provides putative interesting incentives for future research.
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2021
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Characterization of positively charged polyplexes by tunable resistive pulse sensing
With the approval of the first siRNA-based drugs, non-viral siRNA delivery has gained special interest in industry and academia in the last two years. For non-viral delivery, positively charged lipid and polymer formulations play a central role in research and development. However, nanoparticle size characterization, particularly of polydisperse formulations, can be very challenging. Tunable resistive pulse sensing for particle by particle measurements of size, polydispersity, zeta potential and a direct concentration promises better assessment of nanoparticle formulations. However, the current application is not optimized for positively charged particles. A supplier-provided coating solution for difficult-to-measure samples does not allow for successful measurements of positively charged nanoparticles. This article describes a new coating solution based on choline-chloride. Coating is verified by current–voltage (I-V) recordings and ultimately tested on a positively charged nanoparticle formulation comprising of siRNA and PEG-PCL-PEI polymer. This coating allows successful size, polydispersity index (PDI) and concentration measurement by tunable resistive pulse sensing of positively charged PEI-based polyplexes. This article provides the foundation for further characterization of polyplexes as well as other positively charged nanoparticle formulations based on particle by particle measurements.
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2021
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Characterization of systemic immunosuppression by IDH mutant glioma small extracellular vesicles
Background Gliomas are the most common primary brain tumors and are universally fatal. Mutations in the isocitrate dehydrogenase genes (IDH1 and IDH2) define a distinct glioma subtype associated with an immunosuppressive tumor microenvironment. Mechanisms underlying systemic immunosuppression in IDH mutant (mutIDH) gliomas are largely unknown. Here, we define genotype-specific local and systemic tumor immunomodulatory functions of tumor-derived glioma small extracellular vesicles (TEX). Methods TEX produced by human and murine wildtype and mutant IDH glioma cells (wtIDH and mutIDH, respectively) were isolated by size exclusion chromatography (SEC). TEX morphology, size, quantity, molecular profiles and biodistribution were characterized. TEX were injected into naive and tumor-bearing mice, and the local and systemic immune microenvironment composition was characterized. Results Using in vitro and in vivo glioma models, we show that mutIDH TEX are more numerous, possess distinct morphological features and are more immunosuppressive than wtIDH TEX. mutIDH TEX cargo mimics their parental cells, and induces systemic immune suppression in naive and tumor-bearing mice. TEX derived from mutIDH gliomas and injected into wtIDH tumor-bearing mice reduce tumor-infiltrating effector lymphocytes, dendritic cells and macrophages, and increase circulating monocytes. Astonishingly, mutIDH TEX injected into brain tumor-bearing syngeneic mice accelerate tumor growth and increase mortality compared with wtIDH TEX. Conclusions Targeting of mutIDH TEX represents a novel therapeutic approach in gliomas.
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2021
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Characterizing KRAS Membrane Structures by Data-Driven Molecular Docking
Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA, 2 NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA, 3 Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA, 4 Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA, 5 Data Science, Argonne National Laboratory, Lemont, IL, USA, 6 Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM, USA. KRAS is a GTPase that plays an important role in cell growth and signaling pathways. of the different RAS isoforms, KRAS also has the highest prevalence of mutations related to human cancers, making it an attractive therapeutic target in these cases. Once attached to the membrane, KRAS in the active (GTP) form is capable to bind effector proteins, like RAF kinase. However, certain molecular details concerning KRAS conformation and orientational changes when interacting with the membrane and binding partners are not fully understood. To provide new insights, we used a variety of biophysical approaches to characterize KRAS structure and dynamics. Here, we focus on our results utilizing data-driven computational docking to investigate both KRAS and KRAS/ RAF1-RBD (RAS Binding Domain) complex at the membrane. with the HADDOCK program, we incorporated experimental restraints derived from our NMR paramagnetic relaxation enhancement (PRE) and neutron reflectivity (NR) measurements to dock these KRAS forms to a 70:30 POPC:POPS lipid membrane surface. Using NMR-PRE restraints alone, we performed one series of docking runs with the KRAS G-domain directly interacting with the membrane to discern membrane-proximal states. Based on our experimental evidence, and particularly from NR, a highly populated membrane-distal state also exists, where the G-domain does not directly contact the membrane but KRAS remains tethered via the C-terminal hypervariable region (HVR). Therefore, we also conducted a second series of docking runs that incorporated both NMR-PRE and NR restraints to better elucidate the conformations in this state. From these results, we were able to generate atomistic models for KRAS and KRAS/RAF1-RBD with averaged 1-D profiles closely matching the respective NR profiles. Overall, the findings should assist in elucidating the role of KRAS structural dynamics in recruiting effectors, like RAF kinase, to the membrane for activation.
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2021
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Chemical Modification of Bovine Milk Exosomes, the Biological Nanoparticles of the Future, as a Contrast Agent and Drug Delivery Vehicle
Chemically derived nanoparticles are widely used across many applications. While they showed great promise when first discovered, the main hurdles, such as clearance and targeting, have yet to be overcome. A recently discovered class of biological nanoparticles have the potential to circumvent these disadvantages. Exosomes are biological nanoparticles (30 – 150 nm) excreted from most mammalian cells. While exosomes are typically involved in cellular signaling and traditionally removed from the body to be examined for biomarkers, this work combines chemical modifications and a biological particle for diagnostics and treatment of solid tumor cancer. Exosome involvement in cancer treatment has grown over the past ten years with the encapsulation of RNA, proteins and traditional chemotherapeutics. However, this work takes these ideas and drives them into the future by using bovine milk derived exosomes as (1) an ultrasound contrasting agent and (2) a targeted and triggered chemotherapeutic drug delivery vehicle. As an ultrasound contrast agent, raw and pasteurized bovine milk exosomes were tested and found to be capable of echogenicity without altering the ability to identify key features of the exosome, including the presence of CD63 and miRNA. In the second part of this work a chemically synthesized, hypoxia responsive lipid and a tumor penetrating and targeting peptide, iRGD were integrated into the lipid bilayer of the exosome for chemotherapeutic drug delivery. These modified exosomes were characterized using a variety of techniques, including a novel adhesion assay, atomic force microscopy, and high-resolution transmission electron microscopy. The functional capacity of the modified exosomes to deliver doxorubicin to Triple Negative Breast Cancer (TNBC) cells was also evaluated using a combination of cellular internalization and cytotoxicity assays in both monolayer and 3D spheroid cultures. Overall exosomes have the iv ability to be chemically modified in a variety of ways, opening a door to a new approach to nanoparticle drug delivery and targeted imaging.
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2021
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Circulating Extracellular Vesicle Cargo as Bioinformants of 'at-risk'Carotid Artery Stenosis
Objectives Carotid artery atherosclerosis is a major cause of ischemic stroke. Managing patients with asymptomatic disease remains challenging, given the lack of reliable tests to identify the subgroup of patients prone to plaque progression and stroke. Given the functional and diagnostic roles of extracellular vesicle (EV) contents, we hypothesized that plasma EV-derived microRNA (miRNA) differs between symptomatic and asymptomatic patients. Methods EVs were isolated via serial centrifugation followed by enrichment using size exclusion chromatography (SEC) (qEVoriginal columns 70 nm; Izon Science Ltd). EV isolation was confirmed according to MISEV 2018 guidelines: Western blot analysis of common EV markers (CD63, CD81, Alix), nanoparticle tracking analysis (NTA), and cryogenic transmission electron microscopy (Cryo-TEM). Lipoprotein contamination was assessed via enzyme-linked immunosorbent assay of individual SEC fractions (R&D Systems; DAPA10, DAPB00). Next-generation sequencing was performed on EVs (HTG Molecular Diagnostics, Inc.), and differential miRNA expression evaluated using Partek Genomics Suite software (version 8.0). Results Twelve patient plasma samples were collected (n = 6 symptomatic; n = 6 asymptomatic). The average age of the cohort was 70.0 ± 5.7 years (asymptomatic, 67.0 ± 5.5 vs symptomatic, 72.5 ± 5.5 years). All patients had severe stenoses with similar peak systolic velocity (asymptomatic 403.2 ± 84.43 vs symptomatic 371.6 ± 175.25; P = .50) and internal carotid artery (ICA):common carotid artery (CCA) ratios (asymptomatic, 5.36 ± 1.07 vs symptomatic, 7.3 ± 5.00; P = .50). CD63 expression confirmed EV enrichment in fractions 7 to 10, with minimal lipoprotein contamination. EV isolation was further confirmed by CD81 and Alix expression (n = 3 patient samples per group). Cryo-TEM identified EVs as bi-layered nanoparticles with electron dense cores (Fig 1). NTA revealed no significant differences in EV concentration or size between groups (n = 3; P > .05). Principal component and heatmap analysis of miRNA sequencing data revealed symptomatic carotid plasma samples clustered together, whereas asymptomatic samples were either starkly different (n = 5) or approximated the symptomatic profiles (n = 1), suggesting a disease gradient (Fig 2). When symptomatic carotid plasma EV-miRNA profiles were compared with asymptomatic specimens, 190 miRNAs were differentially expressed, with miRNA-654-5p and miRNA-127-3p being the most upregulated, and downregulated, respectively (P < .05, fold-change −2< or >2, excluding miRNA with counts <100). Gene set enrichment identified regulation of protein metabolic processes, and negative regulation of cell communication, signaling, and signal transduction as predicted targets of differentially expressed EV-miRNA (P-value < .05). Conclusions Plasma EV-miRNA profiles may differentiate symptomatic vs asymptomatic carotid stenosis and, together with clinical characteristics, may be used in risk stratification of asymptomatic patients.
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2021
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Circulating extracellular vesicles from patients with acute chest syndrome disrupt adherens junctions between endothelial cells
Background Small cell-derived extracellular vesicles (EVs) can affect endothelial function. We previously found that patients with sickle cell disease (SCD) have greater numbers of circulating EVs than subjects without the disease, and the EVs differentially disrupt endothelial integrity in vitro. Because endothelial disruption is a critical component of acute chest syndrome (ACS), we hypothesized that EVs isolated during ACS would induce greater endothelial damage than those isolated at baseline. Methods Nine pediatric subjects had plasma isolated at baseline and during ACS from which EVs were isolated. Cultured microvascular endothelial cells were treated with EVs and then studied by immunofluorescence microscopy to localize VE-cadherin and F-actin. Results The EVs had a diameter of 95 nm. They contained CD63 and flotillin-1, which were increased in SCD patients (5–13-fold compared to control) and further increased between baseline and ACS (24–57%). The EVs contained hemoglobin, glycophorin A, and ferritin. Treatment with baseline EVs caused modest separation of endothelial cells, while ACS EVs caused substantial disruptions of the endothelial cell monolayers. EVs from subjects with ACS also caused a 50% decrease in protein levels of VE-cadherin. Conclusions These results suggest that circulating EVs can modulate endothelial integrity contributing to the development of ACS in SCD patients by altering cadherin-containing intercellular junctions. Impact - Sickle cell disease patients have circulating extracellular vesicles (EVs) that modulate endothelial integrity by altering cadherin-containing intercellular junctions. - - Disruption is more severe by EVs obtained during acute chest syndrome (ACS). - - These results expand our knowledge of the pathophysiology of acute chest syndrome and the vasculopathies of sickle cell disease.
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2021
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Circulating Serum Exosomal Long Non-Coding RNAs FOXD2-AS1, NRIR, and XLOC_009459 as Diagnostic Biomarkers for Colorectal Cancer
Background: Exosomes derived from cancer cells encapsulate various kinds of tumor-specific molecules and thus can interact with adjacent or distant cells to mediate information exchange. Long non-coding RNAs (lncRNAs) in exosomes have the potential as diagnostic and prognostic biomarkers in different types of cancers. The current study was aimed to identify circulating exosomal lncRNAs for the diagnosis of colorectal cancer (CRC). Methods: Exosomes were isolated from the serum by ultracentrifugation and verified by transmission electron microscope (TEM), qNano, and immunoblotting. Exosomal lncRNAs FOXD2-AS1, NRIR, and XLOC_009459 were selected by lncRNA microarray and validated by qPCR in 203 CRC patients and 201 healthy donors. The receiver operating characteristic curve (ROC) was used to assess the diagnostic efficiency of serum exosomal lncRNAs. Results: Exosomal FOXD2-AS1, NRIR, and XLOC_009459 (TCONS_00020073) levels were significantly upregulated in 203 CRC patients and 80 early-stage CRC patients compared to 201 healthy donors, possessing the area under the curve (AUC) of 0.728, 0.660, and 0.682 for CRC, as well as 0.743, 0.660, and 0.689 for early-stage CRC, respectively. Notably, their combination demonstrated the markedly elevated AUC of 0.736 for CRC and 0.758 for early-stage CRC, indicating their potential as diagnostic biomarkers for CRC. Conclusions: Our data suggested that exosomal lncRNAs FOXD2-AS1, NRIR, and XLOC_009459 act as the promising biomarkers for the diagnostics of CRC and early-stage CRC.
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2021
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Comparative proteome profiling in exosomes derived from porcine colostrum versus mature milk reveals distinct functional proteomes
Exosomes are membranous vesicles of endocytic origin, recently been considered as major players in cell-cell communication. Milk is highly complex, and diverse biocomponents provide adequate nutrition, transfer immunity, and promote adequate neonate development. Milk exosomes are suggested to have a key role in these processes, yet to be further explored, and the alteration of the exosomes' cargo in different stages of lactation stages is important for understanding the factors relevant in nursing and also for improving milk replacer products both for humans and animals. We isolated exosomes from porcine milk in different lactation stages and analyzed their content using a TMT-based high-resolution quantitative proteomic approach. Exosomes were isolated using ultracentrifugation coupled with size exclusion chromatography to enrich milk-derived exosomes in samples obtained at day 0, 7, and 14 after parturition, and characterized by nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. Quantitative proteomics analysis revealed different proteome profiles for colostrum exosomes and milk exosomes. The functional analysis highlighted pathways related to the regulation of homeostasis to be upregulated in colostrum exosomes, and pathways such as endothelial cell development and lipid metabolism to be upregulated in mature milk exosomes. This study endorses the importance of exosomes as active biocomponents of milk and provides knowledge for future studies exploring their role in the regulation of immunity and growth of the newborn.
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2021
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Comparative study of commercial protocols for high recovery of high-purity mesenchymal stem cell-derived extracellular vesicle isolation and their efficient labeling with fluorescent dyes
The extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can be used as carriers for therapeutic molecules and drugs to target disordered tissues. This aimed to compare the protocols used for isolation of MSC-derived EVs by comparing EV collection conditions and three commercial purification kits. We also determined appropriate fluorescent dyes for labeling EVs. MSC-derived EVs were efficiently secreted during cell growth and highly purified by the phosphatidyl serine-based affinity kit. Although the EV membrane was more efficiently labeled with the fluorescent dye PKH67 compared to other probes, the efficiency was not enough to accurately analyze the endothelial cellular uptake of EVs. Results verified the easy protocol for isolating and fluorescently labeling EVs with commercial reagents and kits, but meanwhile, further modification of the protocol is required in order to scale up the amount of EVs derived from MSCs using fluorescent probes. Graphical Abstract The extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can be used as carriers for therapeutic molecules and drugs. This aimed to compare the protocols used for isolation of EVs by comparing EV collection conditions and three commercial purification kits. MSC-derived EVs were efficiently secreted during cell growth and highly purified by the phosphatidyl serine-based affinity kit. Results verified the easy protocol for isolating and fluorescently labeling EVs with commercial reagents and kits, but meanwhile, further modification of the protocol is required in order to scale up the amount of EVs derived from MSCs using fluorescent probes.
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2021
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Comparison and optimization of nanoscale extracellular vesicle imaging by scanning electron microscopy for accurate size-based profiling and morphological analysis
Nanosized extracellular vesicles (EVs) have been found to play a key role in intercellular communication, offering opportunities for both disease diagnostics and therapeutics. However, lying below the diffraction limit and also being highly heterogeneous in their size, morphology and abundance, these vesicles pose significant challenges for physical characterization. Here, we present a direct visual approach for their accurate morphological and size-based profiling by using scanning electron microscopy (SEM). To achieve that, we methodically examined various process steps and developed a protocol to improve the throughput, conformity and image quality while preserving the shape of EVs. The study was performed with small EVs (sEVs) isolated from a non-small-cell lung cancer (NSCLC) cell line as well as from human serum, and the results were compared with those obtained from nanoparticle tracking analysis (NTA). While the comparison of the sEV size distributions showed good agreement between the two methods for large sEVs (diameter > 70 nm), the microscopy based approach showed a better capacity for analyses of smaller vesicles, with higher sEV counts compared to NTA. In addition, we demonstrated the possibility of identifying non-EV particles based on size and morphological features. The study also showed process steps that can generate artifacts bearing resemblance with sEVs. The results therefore present a simple way to use a widely available microscopy tool for accurate and high throughput physical characterization of EVs.
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2021
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Comparison of extracellular vesicle isolation and storage methods using high-sensitivity flow cytometry
Extracellular vesicles (EVs) are of interest for a wide variety of biomedical applications. A major limitation for the clinical use of EVs is the lack of standardized methods for the fast and reproducible separation and subsequent detection of EV subpopulations from biofluids, as well as their storage. To advance this application area, fluorescence-based characterization technologies with single-EV resolution, such as high-sensitivity flow cytometry (HS-FCM), are powerful to allow assessment of EV fractionation methods and storage conditions. Furthermore, the use of HS-FCM and fluorescent labeling of EV subsets is expanding due to the potential of high-throughput, multiplex analysis, but requires further method development to enhance the reproducibility of measurements. In this study, we have applied HS-FCM measurements next to standard EV characterization techniques, including nanoparticle tracking analysis, to compare the yield and purity of EV fractions obtained from lipopolysaccharide-stimulated monocytic THP-1 cells by two EV isolation methods, differential centrifugation followed by ultracentrifugation and the exoEasy membrane affinity spin column purification. We observed differences in EV yield and purity. In addition, we have investigated the influence of EV storage at 4°C or -80°C for up to one month on the EV concentration and the stability of EV-associated fluorescent labels. The concentration of the in vitro cell derived EV fractions was shown to remain stable under the tested storage conditions, however, the fluorescence intensity of labeled EV stored at 4°C started to decline within one day.
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2021
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Comparison of isolation methods using commercially available kits for obtaining extracellular vesicles from cow milk
Extracellular vesicles (EV) are important for delivering biologically active substances to facilitate cell-to-cell communication. Milk-derived EV are widely known because of their potential for immune enhancement. However, procedures for isolating milk-derived EV have not been fully established. To obtain pure milk-derived EV and accurately reveal their function, such procedures must be established. The aim of the present study was to compare methods using commercially available kits for isolating milk-derived EV. Initially, we investigated procedures to remove casein, which is the major obstacle in determining milk-derived EV purity. We separated whey using centrifugation only, acetic acid precipitation, and EDTA precipitation. Then, we isolated milk-derived EV by ultracentrifugation, membrane affinity column, size exclusion chromatography (SEC), polymer-based isolation, or phosphatidylserine-affinity isolation. Using EV count per milligram of protein, which is a good indicator of purity, we determined that acetic acid precipitation was the best method for removing casein. Using nanoparticle tracking analysis, protein quantity analysis, and RNA quantity analysis, we comprehensively compared each isolation method for its purity and yield. We found that SEC-based qEV column (Izon Science) could collect purer milk-derived EV at higher quantities. Thus, a combination of acetic acid precipitation and qEV can effectively isolate high amounts of pure extracellular vesicles from bovine milk.
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2021
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Comparison of Syringes With Intravitreal Anti-VEGF Drugs: Particle Burden and Protein Aggregates in Brolucizumab, Aflibercept and Bevacizumab
Purpose: In a benchwork particle counting analytical evaluation, the number and type of particles in intravitreal injection formulations of three different agents against vascular endothelial growth factor were investigated. Methods: Commercially available ready-to-use aflibercept and brolucizumab glass syringes, vials containing bevacizumab (off-label use in ophthalmology), and repackaged ready-to-use plastic syringes containing bevacizumab were tested without filtration. Total visible, subvisible, and nanoparticles numbers and size distributions were quantified using light obscuration, flow imaging, resonant mass measurement (RMM), tunable resistive pulse sensing, and dynamic light scattering. Results: Repackaged bevacizumab showed overall low particle numbers, aflibercept showed high numbers of micrometer sized particles but low nanoparticle numbers, brolucizumab showed low to moderate numbers of micrometer sized particles but high nanoparticle numbers. RMM measurements identified particles in the nanometer range as either proteinaceous or silicon oil; the nature of the other particles was not further evaluated. Conclusions: Repackaged bevacizumab shows no inferior particle quality compared to ready-to-use products. It is relevant to study nanoparticle load of the products as the micrometer-sized particle numbers do not in all cases correlate to nanoparticle counts. Particularly for the high concentration product Beovu (brolucizumab), high nanoparticle numbers were found despite low numbers of micrometer sized particles. Silicone oil droplets did not account for high particle numbers as the measured numbers were low. Translational Relevance: Different side effects are registered in different frequencies with different intravitreal anti-VEGF-drugs and syringes, which are applied by injection by small 30G needles through the sclera directly to the intravitreal cavity. The study of nanoparticles and silicone oil droplets may be able to contribute to narrowing down the causes.
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2021
ev vr
Comprehensive analysis and comparison of proteins in salivary exosomes of climacteric and adolescent females
Currently, it is difficult to extract exosomes with stable physicochemical properties from saliva. Furthermore, due to inadequate availability of basic data, the application of salivary exosomes as a diagnostic material is limited. In this study, we aimed to investigate an easier method for extraction of exosomes from whole saliva and compared proteins in salivary exosomes derived from subjects of two age groups. Salivary exosomes were extracted from nine females (56.7 ± 1.17 years old; climacteric or 19.9 ± 0.20 years old; adolescent) using commercial reagents and kits and detected using western blotting with anti-exosome marker antibodies. Exosome particle size and exosome-containing proteins were identified using NanoSight® and liquid chromatography with tandem mass spectrometry, respectively. In addition, an efficient method of exosome extraction from saliva using a reagent and without the use of an ultracentrifuge was shown. Our results showed a higher total protein content and larger particle size in climacteric exosomes than in adolescent exosomes. However, adolescent exosomes showed a larger variety of proteins (780 proteins) than the climacteric exosomes (573 proteins). Altogether, 893 proteins were identified in the salivary exosomes. Although viral process-, ribosome- and structural molecule-related proteins were higher in the adolescent exosomes, the levels of major salivary proteins such as immunoglobulins and amylase, were higher in the climacteric exosomes than in the adolescent exosomes. The data presented, which show the fundamental protein composition of salivary exosomes and the changes that occur with age, are beneficial in both diagnostic and biotechnological applications.
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2021
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Dancing with Trojan horses: an interplay between the extracellular vesicles and viruses
Extracellular vesicles (EVs) are membrane-encapsulated particles released by eukaryotic and prokaryotic cells into the extracellular environment. Depending on their origin, size, and composition, EVs are grouped in several classes, with one of them being exosomes, which are small EVs (SEVs) generated within the endosomal compartment of eukaryotic cells via the unique multivesicular body pathway. Being able to deliver their content (proteins, lipids, small molecules, and nucleic acids) to other cells, exosomes/SEVs are considered as bioactive vesicles with multiple biological functions. Importantly, the composition of exosomes/SEVs depends on the cell and tissue of origin including a set of specific proteins. However, the pathological conditions may lead to the appearance of diseases-specific exosomes/SEVs containing pathology-specific cargoes utilized in the malicious cell-cell communication and spread of malady. Viruses demonstrate complex ‘dancing’ around the exosome biogenesis system, being able to hijack the host systems responsible for the exosome biogenesis. They use the exosome biogenesis system to promote packaging of their capsids, regulate virion production, and virus secretion. They also utilize a Trojan horse stratagem to place virions inside the SEVs and thereby to spread beyond their normal range of cell hosts using the normal EV uptake process. Another illustration of the virus-based utilization of Trojan horse strategy is given by the ability of human viruses to use exosomes/SEVs as carriers of their exogenous miRNA or viral proteins to the non-infected cells. Taken together, these strategies of dancing with Trojan horses can help viruses to fight with the host defense and to spread the infection.
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2021
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Deciphering the Structure and Chemical Composition of Drug Nanocarriers: From Bulk Approaches to Individual Nanoparticle Characterization
Drug nanocarriers (NCs) with sizes usually below 200 nm are gaining increasing interest in the treatment of severe diseases such as cancer and infections. Characterization methods to investigate the morphology and physicochemical properties of multifunctional NCs are key in their optimization and in the study of their in vitro and in vivo fate. Whereas a variety of methods has been developed to characterize “bulk” NCs in suspension, the scope of this review is to describe the different approaches for the NC characterization on an individual basis, for which fewer techniques are available. The accent is put on methods devoid of labelling, which could lead to artefacts. For each characterization method, the principles and approaches to analyze the data are presented in an accessible manner. Aspects related to sample preparation to avoid artefacts are indicated, and emphasis is put on examples of applications. NC characterization on an individual basis allows gaining invaluable information in terms of quality control, on: i) NC localization and fate in biological samples; ii) NC morphology and crystallinity; iii) distribution of the NC components (drugs, shells), and iv) quantification of NCs’ chemical composition. The individual characterization approaches are expected to gain increasing interest in the near future.
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2021
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Defining candidate mRNA and protein EV biomarkers to discriminate ccRCC and pRCC from non-malignant renal cells in vitro
Renal cell carcinoma (RCC) accounts for over 400,000 new cases and 175,000 deaths annually. Diagnostic RCC biomarkers may prevent overtreatment in patients with early disease. Extracellular vesicles (EVs) are a promising source of RCC biomarkers because EVs carry proteins and messenger RNA (mRNA) among other biomolecules. We aimed to identify biomarkers and assess biological functions of EV cargo from clear cell RCC (ccRCC), papillary RCC (pRCC), and benign kidney cell lines. EVs were enriched from conditioned cell media by size exclusion chromatography. The EV proteome was assessed using Tandem Mass Tag mass spectrometry (TMT-MS) and NanoString nCounter technology was used to profile 770 cancer-related mRNA present in EVs. The heterogeneity of protein and mRNA abundance and identification highlighted the heterogeneity of EV cargo, even between cell lines of a similar pathological group (e.g., ccRCC or pRCC). Overall, 1726 proteins were quantified across all EV samples, including 181 proteins that were detected in all samples. In the targeted profiling of mRNA by NanoString, 461 mRNAs were detected in EVs from at least one cell line, including 159 that were present in EVs from all cell lines. In addition to a shared EV cargo signature, pRCC, ccRCC, and/or benign renal cell lines also showed unique signatures. Using this multi-omics approach, we identified 34 protein candidate pRCC EV biomarkers and 20 protein and 8 mRNA candidate ccRCC EV biomarkers for clinical validation.
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2021
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Detection of Tumor-Associated Membrane Receptors on Extracellular Vesicles from Non-Small Cell Lung Cancer Patients via Immuno-PCR
Precision cancer medicine for non-small-cell lung cancer (NSCLC) has increased patient survival. Nevertheless, targeted agents towards tumor-associated membrane receptors only result in partial remission for a limited time, calling for approaches which allow longitudinal treatment monitoring. Rebiopsy of tumors in the lung is challenging, and metastatic lesions may have heterogeneous signaling. One way ahead is to use liquid biopsies such as circulating tumor DNA or small extracellular vesicles (sEVs) secreted by the tumor into blood or other body fluids. Herein, an immuno-PCR-based detection of the tumor-associated membrane receptors EGFR, HER2, and IGF-1R on CD9-positive sEVs from NSCLC cells and pleural effusion fluid (PE) of NSCLC patients is developed utilizing DNA conjugates of antibody mimetics and affibodies, as detection agents. Results on sEVs purified from culture media of NSCLC cells treated with anti-EGFR siRNA, showed that the reduction of EGFR expression can be detected via immuno-PCR. Protein profiling of sEVs from NSCLC patient PE samples revealed the capacity to monitor EGFR, HER2, and IGF-1R with the immuno-PCR method. We detected a significantly higher EGFR level in sEVs derived from a PE sample of a patient with an EGFR-driven NSCLC adenocarcinoma than in sEVs from PE samples of non-EGFR driven adenocarcinoma patients or in samples from patients with benign lung disease. In summary, we have developed a diagnostic method for sEVs in liquid biopsies of cancer patients which may be used for longitudinal treatment monitoring to detect emerging bypassing resistance mechanisms in a noninvasive way.
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2021
ev nm vr
Development of a new methodology to determine size differences of nanoparticles with nanoparticle tracking analysis
The current frontiers in Biology thus in Medicine and Pharmacy are at the nanoscale. Indeed, this is the relevant scale for extracting or synthetizing, visualizing, counting, characterizing and/or modifying nanoparticles. Nanoparticles are highly diverse including: extracellular vesicles (e.g.: exosomes), proteins, viruses and nanovectors or drug delivery systems for instance. To quantify the concentration of nano-sized objects, a growing number of size-tracking instruments is being developed. However, to date, the generated data is only used to provide a concentration measurement. The objective of this study was to determine which sizes of nanoparticles are statistically significant between 2 groups of samples. Using different samples (in silico data; calibrated beads; various biological samples), an approach that statistically compares 2 groups of samples was developed and validated. The proof of concept of the proposed approach was illustrated with applications in the field of Biology, Medicine and Pharmacy using liposomes and extracellular vesicles. For the first time to our knowledge, our results suggest that the presented approach enables comparing different groups of biological samples. It may be extended to situations such as batch 1 versus batch 2; healthy versus disease or non-treated versus treated.
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2021
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Development of fast, reliable and automated isolation and fractionation methods for nanosized subpopulations of human biomacromolecules
This doctoral thesis describes the development of fast, reliable and automated isolation and fractionation methods for nanosized subpopulations of human biomacromolecules. The focus of the study was on subpopulations of lipoproteins and extracellular vesicles (EVs) that are important in the detection of different diseases, such as atherosclerotic cardiovascular diseases and cancer, and may even possess therapeutic potential. In the thesis, immunoaffinity chromatography (IAC) with selective antibodies immobilized on the monolithic disk columns were utilized for the selective isolation of biomacromolecules from human plasma, while asymmetrical flow field-flow fractionation (AsFlFFF or AF4) was able to fractionate relevant subpopulations of biomacromolecules (e.g., small dense low-density lipoproteins, exomeres, and exosomes) from the isolates. Continuous flow quartz crystal microbalance (QCM) and partial filling affinity capillary electrophoresis (PF-ACE) were employed to study the affinity of the interactions between the antibody and lipoproteins. The first step was to develop a method to study interactions between antibody and lipoproteins to select a high affinity antibody useful for the isolation of lipoprotein subpopulations by IAC. The interaction data obtained with PF-ACE was analyzed to determine the heterogeneity of the interactions with adsorption energy distribution calculations, while the QCM data was processed with interaction maps. The affinity constants obtained with QCM and PF-ACE agreed well with each other. Next, the IAC methods were developed to capture EVs of different cellular origins from human plasma using anti-CD9 monoclonal antibody (mAb), while anti-CD61 mAb was exploited to capture platelet-derived EVs. The anti-apolipoprotein B-100 (anti-apoB-100) mAb was exploited to immunocapture apoB-100 containing lipoproteins. The anti-apoB-100 mAb was also characterized by the PF-ACE and QCM studies. Appropriate elution conditions were found for the IAC methods, which has often been an issue with magnetic beads-based immunoaffinity methods. Since IAC allowed selective isolation of EVs and lipoproteins, a size-based separation to their subpopulations with AsFlFFF was introduced as a successive step. This enabled additional characterization of subpopulations by nanoparticle tracking analysis, western blotting, electron microscopy, capillary electrophoresis coupled with laser-induced fluorescent detection, zeta potential measurements, as well as free amino acids and glucose analysis with hydrophilic interaction liquid chromatography-tandem mass spectrometry. Finally, IAC was successfully on-line coupled to AsFlFFF, resulting in quick and automated isolation and fractionation of the subpopulations of EVs and lipoproteins. The constructed IAC-AsFlFFF system was able to process reliably 18–38 samples in 24 h with only minor operator involvement, resulting in highly reproducible and gentle fractionation of EV subpopulations in the size range of exomeres and exosomes. Polymeric monolithic disk columns were utilized for the first time for the IAC-based isolation of EVs and their subpopulations from human plasma, and for the detection of exomeres in CD9+ EVs and CD61+ platelet-derived EVs from human plasma samples. The results demonstrated that CD61+ EVs are potentially taking part in gluconeogenesis based on free amino acids and glucose present as cargo.
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2021
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Diagnostic potential of extracellular vesicle‑associated microRNA‑10b and tumor markers for lung adenocarcinoma
MicroRNAs (miRNAs/miRs) in extracellular vesicles (EVs) are potential diagnostic markers. The purpose of the present study was to investigate potential EV miRNA biomarkers for lung adenocarcinoma (LUAD). Potential miRNAs were identified by searching public databases and verified by examining clinical samples. The diagnostic value of EV‑associated miR‑10b, plasma miR‑10b and tumor markers (TMs), including α‑fetoprotein (AFP), neuron‑specific enolase, carcinoembryonic antigen (CEA), cytokeratin 19 fragment 21‑1 (CYFRA211), pro‑gastrin‑releasing‑peptide, carbohydrate antigen (CA)125, CA153, CA199 and CA724, was evaluated via receiver operating characteristic curve analysis. By searching the Gene Expression Omnibus and The Cancer Genome Atlas databases, miR‑10b was identified as a potential biomarker. The analysis of clinical samples suggested that EV‑associated miR‑10b from plasma was significantly differentially expressed between LUAD and control samples. EV‑associated miR‑10b could function as a diagnostic marker for LUAD, with an AUC of 0.998, which was higher than the AUCs for TMs such as AFP, CEA, CYFRA211, CA125, CA153, CA199, CA724, pro‑gastrin‑releasing‑peptide and neuron‑specific enolase. In conclusion, EV‑associated miR‑10b may be a potential diagnostic biomarker for LUAD that is superior to plasma miR‑10b and TMs.
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2021
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Dually targeted bioinspired nanovesicle delays advanced prostate cancer tumour growth in vivo
Prostate cancer (PC) is second-leading cancer in men, with limited treatment options available for men with advanced and metastatic PC. Prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) have been exploited as therapeutic targets in PC due to their upregulation in the advanced stages of the disease. To date, several PSA- and PSMA-activatable prodrugs have been developed to reduce the systemic toxicity of existing chemotherapeutics. Bioinspired nanovesicles have been exploited in drug delivery, offering prolonged drug blood circulation and higher tumour accumulation. For the first time, this study describes the engineering of dually targeted PSA/PSMA nanovesicles for advanced PC. PSMA-targeted bioinspired hybrids were prepared by hydrating a lipid film with anti-PSMA-U937 cell membranes and DOX-PSA prodrug, followed by extrusion. The bioinspired hybrids were characterised using dynamic light scattering, transmission electron microscopy, Dot blot, flow cytometry and Western blot. Cellular binding and toxicity studies in PC cancer cell lines were carried out using flow cytometry, confocal microscopy, and resazurin assay. Finally, tumour targeting and therapeutic efficacy studies were performed in solid and metastatic C4-2B-tumor-bearing mice. Interestingly, our PSMA-targeted hybrids demonstrated high cell uptake in PSMA-expressing cells with significant accumulation in solid and metastatic C4-2B tumour tissues following intravenous administration. More promisingly, our dually targeted PSA/PSMA hybrid significantly slowed down the C4-2B tumour growth in vivo, compared to free DOX-PSA and non-targeted PSA-hybrid. Our PSA/PSMA bioinspired hybrid could offer a highly selective treatment for advanced PC with lower side effects. Statement of significance This study investigates a new approach to treat prostate cancer using dually targeted bioinspired nanovesicle . Our bioinspired vesicles are made mainly of a human blood cell membrane with a ligand recognising a specific marker (PSMA) on the surface of the prostate cancer cells. The present work describes the successful loading of a doxorubicin prodrug linked to a PSA- activatable peptide into these targeted bioinspired nanovesicle , where the active PSA enzyme presents in these cells converts the drug to its active form. Our dually targeted PSA/PSMA hybrid vesicles has successfully improved site-specific prodrug delivery to tackle advanced prostate cancer, offering a novel and effective prostate cancer treatment.
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2021
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Effects of endurance racing on horse plasma extracellular particle miRNA
Background Physical exercise is an essential factor in preventing and treating metabolic diseases by promoting systemic benefits throughout the body. The molecular factors involved in this process are poorly understood. Micro RNAs (miRNAs) are small non‐coding RNAs that inhibit mRNA transcription. MiRNAs, which can participate in the benefits of exercise to health, circulate in plasma in extracellular particles (EP). Horses that undergo endurance racing are an excellent model to study the impact of long‐duration/low intensity exercise in plasma EP miRNAs. Objectives To evaluate the effects of 160 km endurance racing on horse plasma extracellular particles and their miRNA population. Study design Cohort study. Methods We collected plasma from 5 Arabian horses during five time‐points of an endurance ride. Extracellular particles were purified from plasma and characterised by electron microscopy, resistive pulse sensing (qNano), and western blotting. Small RNAs were purified from horse plasma EP, and sequencing was performed. Results Endurance racing increased EP concentration and average diameter compared to before the race. Western blotting showed a high concentration of extracellular vesicles proteins 2 h after the race, which returned to baseline 15 h after the race. MicroRNA differential expression analysis revealed increasing levels of eca‐miR‐486‐5p during and after the race, and decreasing levels of eca‐miR‐9083 after the end. Conclusions This study adds new data about the variation in plasma EP concentrations after long‐distance exercise and brings new insights about the roles of exercise‐derived EP miRNAs during low‐intensity endurance exercise.
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2021
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Effects of exercise on exosome release and cargo in in vivo and ex vivo models: A systematic review
Exercise-released exosomes have been identified as novel players to mediate cell-to-cell communication in promoting systemic beneficial effects. This review aimed to systematically investigate the effects of exercise on exosome release and cargo, as well as provide an overview of their physiological implications. Among the 436 articles obtained in the database search (WOS, Scopus, and PubMed), 19 articles were included based on eligibility criteria. Results indicate that exercise promotes the release of exosomes without modification of its vesicle size. The literature has primarily shown an exercise-driven increase in exosome markers (Alix, CD63, CD81, and Flot-1), along with other exosome-carried proteins, into circulation. However, exosome isolation, characterization, and phenotyping methodology, as well as timing of sample recovery following exercise can influence the analysis and interpretation of findings. Moreover, a large number of exosome-carried microRNAs (miRNAs), including miR-1, miR-133a, miR-133b, miR-206, and miR-486, in response to exercise are involved in the modulation of proliferation and differentiation of skeletal muscle tissue, although antigen-presenting cells, leukocytes, endothelial cells, and platelets are the main sources of exosome release into the circulation. Collectively, with the physiological implications as evidenced by the ex vivo trials, the release of exercise-promoted exosomes and their cargo could provide the potential therapeutic applications via the role of intercellular communication.
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2021
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Effects of exosomes derived from human umbilical vein endothelial cells on apoptosis of pre-chondrogenic cells stimulated by inflammatory factors
·To investigate the effect of exosomes derived from umbilical vein endothelial cells (HUVECs) on apoptosis of murine pre-chondrogenic cell line ATDC5 cells under inflammatory stimulation. ·The exosomes derived from HUVECs were isolated by using an exosome isolation kit. Western blotting was used to detect the exosome marker proteins, including tumor susceptibility gene 101 (Tsg101), cluster differentiation 9 (CD9) and apoptosis linked gene-2-interacting protein X (Alix). The morphology of exosomes was observed by transmission electron microscope, and the size of exosomes was identified by particle size detection. Fluorescence microscope was used to observe the ATDC5 cell uptake of exosomes and the production of reactive oxygen species (ROS). TUNEL staining and flow cytometry were used to examine the effect of exosomes on ATDC5 cell apoptosis stimulated by interleukin-1β (IL-1β). Western blotting was used to detect the effect of exosomes on the expression levels of ATDC5 apoptosis-related proteins such as B-cell lymphoma/leukemia 2 (Bcl-2), Bcl-2 associated X protein (Bax), cleaved caspase-3 (c-caspase-3) and anti-oxidative stress-related proteins such as nuclear factor E2 related factor 2 (Nrf-2), Kelch-like ECH-associated protein 1 (Keap-1), heme oxygenase 1 (HO-1) and NADPH quinone oxidoreductase-like protein 1 (NQO-1) under IL-1β stimulation. ·Under the transmission electron microscope, the HUVEC-derived exosomes were oval, hollow, double-layered, and positively expressed exosome markers CD9, Alix and Tsg101. Compared with the ATDC5 cells stimulated by IL-1β, ATDC5 cells stimulated by IL-1β incubated with exosomes had higher level of ROS (P=0.000) and higher apoptosis rate (P=0.000). The expression of Bax, c-caspase-3 and Keap-1 increased, and the expression of Bcl-2, Nrf-2, HO-1 and NQO-1 decreased in ATDC5 cells exposed to IL-1β and exosomes compared to ATDC5 cells only exposed to IL-1β. ·HUVEC-derived exosomes may promote ATDC5 cells apoptosis under the stimulation of IL-1β by inhibiting the ability of ATDC5 cell to resist oxidative stress.
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2021
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Effects of Solidification Conditions on Grain Refinement Capacity of TiC in Directionally Solidified Ti6Al4V Alloy
In this study, the effects of solidification conditions on the grain refinement capacity of heterogeneous nuclei TiC in directionally solidified Ti6Al4V alloy were investigated using experimental and numerical approaches. Ti6Al4V powder with and without TiC particles in a Ti6Al4V sheath was melted and directionally solidified at various solidification rates via the floating zone melting method. In addition, by using the phase field method, the microstructural evolution of directionally solidified Ti6Al4V was simulated by varying the temperature gradient G and solidification rate V. As the solidification rate increased, the increment of the prior β grain number by TiC addition also increased. There are two reasons for this: first, the amount of residual potent heterogeneous nuclei TiC is larger. Second, the amount of TiC particles that can nucleate becomes larger. This is because increasing the constitutional undercooling ΔTc leads to the activation of a smaller radius of heterogeneous nuclei and a higher nucleation probability from each radius. At a cooling rate R higher than that in the floating zone melting experiment (R = 3 to 1000 K/s), the maximum degree of constitutional undercooling ΔTc,Max has a peak value, which suggests that constitutional undercooling ΔTc has a smaller contribution at higher cooling rates, such as those that occur during electron beam melting (EBM), including laser powder bed fusion (LPBF).
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2021
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Embryonic stem cell-derived exosomes attenuate transverse aortic constriction induced heart failure by increasing angiogenesis
Background: Although there are concerns regarding their clinical use, embryonic stem cells (ESCs) hold a great promise for cardiac repair. Exosomes deriving from ESCs constitute a promising alternative for heart restoration. However, their effects in hypertension-induced heart failure are still unknown. Objective and Methods: To investigate the effects of ESCs-derived exosomes on hypertension-induced heart failure and the underlying mechanisms, sustained transverse aortic constriction (TAC) was performed on 8-week-old C57BL/6 male mice. After 1 months, ESCs-derived exosomes were isolated and injected intravenously once a week for 6 weeks. Echocardiography, wheat germ agglutinin (WGA), Masson staining, immunohistochemistry, and tube formation assays were all involved in our study. Results: Proteomics analyses revealed that ESC-derived exosomes contain FGF2 protein. Tube formation induced by these exosomes could be inhibited by FGF2R siRNA interference. ESCs-derived exosomes evidently attenuated TAC-induced heart failure, improving cardiac function and promoting myocardial angiogenesis which can be attenuated by selective FGF2 inhibitor AZD4547. Conclusions: ESC-derived exosomes attenuate TAC-induced heart failure mostly by promoting myocardial angiogenesis. FGF2 signaling plays a vital role in the myocardial angiogenesis induced by ESC-derived exosomes. Keywords: embryonic stem cells, exosomes, angiogenesis, transverse aortic constriction, heart failure
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2021
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Endothelial Progenitor Cell-Derived Extracellular Vesicles: Potential Therapeutic Application in Tissue Repair and Regeneration
Recently, many studies investigated the role of a specific type of stem cell named the endothelial progenitor cell (EPC) in tissue regeneration and repair. EPCs represent a heterogeneous population of mononuclear cells resident in the adult bone marrow. EPCs can migrate and differentiate in injured sites or act in a paracrine way. Among the EPCs’ secretome, extracellular vesicles (EVs) gained relevance due to their possible use for cell-free biological therapy. They are more biocompatible, less immunogenic, and present a lower oncological risk compared to cell-based options. EVs can efficiently pass the pulmonary filter and deliver to target tissues different molecules, such as micro-RNA, growth factors, cytokines, chemokines, and non-coding RNAs. Their effects are often analogous to their cellular counterparts, and EPC-derived EVs have been tested in vitro and on animal models to treat several medical conditions, including ischemic stroke, myocardial infarction, diabetes, and acute kidney injury. EPC-derived EVs have also been studied for bone, brain, and lung regeneration and as carriers for drug delivery. This review will discuss the pre-clinical evidence regarding EPC-derived EVs in the different disease models and regenerative settings. Moreover, we will discuss the translation of their use into clinical practice and the possible limitations of this process.
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2021
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Enhancing the Stabilization Potential of Lyophilization for Extracellular Vesicles
Extracellular vesicles (EV) are an emerging technology as immune therapeutics and drug delivery vehicles. However, EVs are usually stored at −80 °C which limits potential clinical applicability. Freeze-drying of EVs striving for long-term stable formulations is therefore studied. The most appropriate formulation parameters are identified in freeze-thawing studies with two different EV types. After a freeze-drying feasibility study, four lyophilized EV formulations are tested for storage stability for up to 6 months. Freeze-thawing studies revealed improved colloidal EV stability in presence of sucrose or potassium phosphate buffer instead of sodium phosphate buffer or phosphate-buffered saline. Less aggregation and/or vesicle fusion occurred at neutral pH compared to slightly acidic or alkaline pH. EVs colloidal stability can be most effectively preserved by addition of low amounts of poloxamer 188. Polyvinyl pyrrolidone failed to preserve EVs upon freeze-drying. Particle size and concentration of EVs are retained over 6 months at 40 °C in lyophilizates containing 10 mm K- or Na-phosphate buffer, 0.02% poloxamer 188, and 5% sucrose. The biological activity of associated beta-glucuronidase is maintained for 1 month, but decreased after 6 months. Here optimized parameters for lyophilization of EVs that contribute to generate long-term stable EV formulations are presented.
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2021
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Enzymatically active apurinic/apyrimidinic endodeoxyribonuclease 1 is released by mammalian cells through exosomes
The apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1), the main AP-endonuclease of the DNA base excision repair pathway, is a key molecule of interest to researchers due to its unsuspected roles in different nonrepair activities, such as: i) adaptive cell response to genotoxic stress, ii) regulation of gene expression, and iii) processing of microRNAs, which make it an excellent drug target for cancer treatment. We and others recently demonstrated that APE1 can be secreted in the extracellular environment and that serum APE1 may represent a novel prognostic biomarker in hepatocellular and non-small-cell lung cancers. However, the mechanism by which APE1 is released extracellularly was not described before. Here, using three different approaches for exosomes isolation: commercial kit, nickel-based isolation, and ultracentrifugation methods and various mammalian cell lines, we elucidated the mechanisms responsible for APE1 secretion. We demonstrated that APE1 p37 and p33 forms are actively secreted through extracellular vesicles (EVs), including exosomes from different mammalian cell lines. We then observed that APE1 p33 form is generated by proteasomal-mediated degradation and is enzymatically active in EVs. Finally, we revealed that the p33 form of APE1 accumulates in EVs upon genotoxic treatment by cisplatin and doxorubicin, compounds commonly found in chemotherapy pharmacological treatments. Taken together, these findings provide for the first time evidence that a functional Base Excision Repair protein is delivered through exosomes in response to genotoxic stresses, shedding new light into the complex noncanonical biological functions of APE1 and opening new intriguing perspectives on its role in cancer biology.
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2021
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Estradiol driven metabolism in transwomen associates with reduced circulating extracellular vesicle microRNA-224/452
Objective Sex steroid hormones like estrogens have a key role in the regulation of energy homeostasis and metabolism. In transwomen, gender-affirming hormone therapy like estradiol (in combination with antiandrogenic compounds) could affect metabolism as well. Given that the underlying pathophysiological mechanisms are not fully understood, this study assessed circulating estradiol-driven microRNAs (miRs) in transwomen and their regulation of genes involved in metabolism in mice. Methods Following plasma miR-sequencing (seq) in a transwomen discovery (n = 20) and validation cohort (n = 30), we identified miR-224 and miR-452. Subsequent systemic silencing of these miRs in male C57Bl/6 J mice (n = 10) was followed by RNA-seq-based gene expression analysis of brown and white adipose tissue in conjunction with mechanistic studies in cultured adipocytes. Results Estradiol in transwomen lowered plasma miR-224 and -452 carried in extracellular vesicles (EVs) while their systemic silencing in mice and cultured adipocytes increased lipogenesis (white adipose) but reduced glucose uptake and mitochondrial respiration (brown adipose). In white and brown adipose tissue, differentially expressed (miR target) genes are associated with lipogenesis (white adipose) and mitochondrial respiration and glucose uptake (brown adipose). Conclusion This study identified an estradiol-drive post-transcriptional network that could potentially offer a mechanistic understanding of metabolism following gender-affirming estradiol therapy.
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2021
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Evaluating comparative β-glucan production aptitude of Saccharomyces cerevisiae, Aspergillus oryzae, Xanthomonas campestris, and Bacillus natto
β-glucan is a natural polysaccharide derivative composed of a group of glucose monomers with β-glycoside bonds that can be synthesized intra- or extra-cellular by various microorganisms such as yeasts, bacteria, and moulds. The study aimed to discover the potential of various microorganisms such as Saccharomyces cerevisiae, Aspergillus oryzae, Xanthomonas campestris, and Bacillus natto in producing β-glucan. The experimental method used and the data were analyzed descriptively. The four microorganisms above were cultured under a submerged state in Yeast glucose (YG) broth for 120 h at 30 °C with 200 rpm agitation. During the growth, several parameters were examined including total population by optical density, the pH, and glucose contents of growth media. β-glucan was extracted using acid-alkaline methods from the growth media then the weight was measured. The results showed that S. cerevisiae, A. oryzae X. campestris, and B. natto were prospective for β-glucans production in submerged fermentation up to 120 h. The highest β-glucans yield was shown by B. natto (20.38%) with the β-glucans mass of 1.345 ± 0.08 mg and globular diameter of 600 μm. The highest β-glucan mass was achieved by A. oryzae of 82.5 ± 0.03 mg with the total population in optical density of 0.1246, a final glucose level of 769 ppm, the pH of 6.67, and yield of 13.97% with a globular diameter of 1400 μm.
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2021
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Evidence of Immune Modulators in the Secretome of the Equine Tapeworm Anoplocephala perfoliata
Anoplocephala perfoliata is a neglected gastro-intestinal tapeworm, commonly infecting horses worldwide. Molecular investigation of A. perfoliata is hampered by a lack of tools to better understand the host–parasite interface. This interface is likely influenced by parasite derived immune modulators released in the secretome as free proteins or components of extracellular vesicles (EVs). Therefore, adult RNA was sequenced and de novo assembled to generate the first A. perfoliata transcriptome. In addition, excretory secretory products (ESP) from adult A. perfoliata were collected and EVs isolated using size exclusion chromatography, prior to proteomic analysis of the EVs, the EV surface and EV depleted ESP. Transcriptome analysis revealed 454 sequences homologous to known helminth immune modulators including two novel Sigma class GSTs, five α-HSP90s, and three α-enolases with isoforms of all three observed within the proteomic analysis of the secretome. Furthermore, secretome proteomics identified common helminth proteins across each sample with known EV markers, such as annexins and tetraspanins, observed in EV fractions. Importantly, 49 of the 454 putative immune modulators were identified across the secretome proteomics contained within and on the surface of EVs in addition to those identified in free ESP. This work provides the molecular tools for A. perfoliata to reveal key players in the host–parasite interaction within the horse host.
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2021
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Evidence of Immune Modulators in the Secretome of the Equine Tapeworm Anoplocephala perfoliata. Pathogens 2021, 10, 912
Anoplocephala perfoliata is a neglected gastro-intestinal tapeworm, commonly infecting horses worldwide. Molecular investigation of A. perfoliata is hampered by a lack of tools to better understand the host–parasite interface. This interface is likely influenced by parasite derived immune modulators released in the secretome as free proteins or components of extracellular vesicles (EVs). Therefore, adult RNA was sequenced and de novo assembled to generate the first A. perfoliata transcriptome. In addition, excretory secretory products (ESP) from adult A. perfoliata were collected and EVs isolated using size exclusion chromatography, prior to proteomic analysis of the EVs, the EV surface and EV depleted ESP. Transcriptome analysis revealed 454 sequences homologous to known helminth immune modulators including two novel Sigma class GSTs, five α-HSP90s, and three α-enolases with isoforms of all three observed within the proteomic analysis of the secretome. Furthermore, secretome proteomics identified common helminth proteins across each sample with known EV markers, such as annexins and tetraspanins, observed in EV fractions. Importantly, 49 of the 454 putative immune modulators were identified across the secretome proteomics contained within and on the surface of EVs in addition to those identified in free ESP. This work provides the molecular tools for A. perfoliata to reveal key players in the host–parasite interaction within the horse host.
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2021
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Exosomal CD47 plays an essential role in immune evasion in ovarian cancer
Ovarian cancer is largely diagnosed at advanced stages upon detection of multiple peritoneal dissemination, resulting in poor outcomes. CD47 is overexpressed in tumors, facilitates tumor immune evasion, and is located on exosomes. We aimed to investigate the role of exosomal CD47 in ovarian cancer progression. Prognostic significance of CD47 expression in ovarian cancer was examined using a public database including 1,435 patients and validated with 26 patients at our institution. CD47 expression was associated with poor progression-free survival and inversely correlated with macrophage infiltration in ovarian cancer tissues. Exosomes were collected from ovarian cancer cell lines, and CD47 expression on exosomes was confirmed via flow cytometry. Inhibition of exosome secretion with GW4869 and exosome uptake with 5-(N-ethyl-N-isopropyl)-amiloride inhibited the surface CD47 expression on ovarian cancer cells and promoted phagocytosis by macrophages. RAB27A (a key regulator of exosome release) knockdown inhibited exosome secretion and led to CD47 downregulation in ovarian cancer cells. In a xenograft mouse model, suppression of the release of tumor-derived exosomes by GW4869 or RAB27A knockdown suppressed tumor progression and enhanced M1 macrophage phagocytosis in cancer tissues. Collectively, CD47 expression was correlated with poor prognoses in patients with ovarian cancer, suggesting the importance of immune evasion. CD47 was expressed on exosomes and the inhibition of exosome secretion and/or uptake enhanced cancer cell phagocytosis by macrophages, and thus, suppressed peritoneal dissemination. This suggests the potential of a novel immune checkpoint therapeutic agent that focuses on exosomes. Implications: Mechanistic insight from the current study suggests that exosomal CD47 may be an advantageous therapeutic target in ovarian cancer.
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2021
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Exosome-Depleted Excretory-Secretory Products of the Fourth-Stage Larval Angiostrongylus cantonensis Promotes Alternative Activation of Macrophages Through Metabolic Reprogramming by the PI3K-Akt Pathway
Angiostrongylus cantonensis (AC), which parasitizes in the brain of the non-permissive host, such as mouse and human, is an etiologic agent of eosinophilic meningitis. Excretory-secretory (ES) products play an important role in the interaction between parasites and hosts’ immune responses. Inflammatory macrophages are responsible for eosinophilic meningitis induced by AC, and the soluble antigens of Angiostrongylus cantonensis fourth stage larva (AC L4), a mimic of dead AC L4, aggravate eosinophilic meningitis in AC-infected mice model via promoting alternative activation of macrophages. In this study, we investigated the key molecules in the ES products of AC L4 on macrophages and observed the relationship between metabolic reprogramming and the PI3K-Akt pathway. First, a co-culture system of macrophage and AC L4 was established to define the role of AC L4 ES products on macrophage polarization. Then, AC L4 exosome and exosome-depleted excretory-secretory products (exofree) were separated from AC L4 ES products using differential centrifugation, and their distinct roles on macrophage polarization were confirmed using qPCR and ELISA experiments. Moreover, AC L4 exofree induced alternative activation of macrophages, which is partially associated with metabolic reprogramming by the PI3K-Akt pathway. Next, lectin blot and deglycosylation assay were done, suggesting the key role of N-linked glycoproteins in exofree. Then, glycoproteomic analysis of exofree and RNA-seq analysis of exofree-treated macrophage were performed. Bi-layer PPI network analysis based on these results identified macrophage-related protein Hexa as a key molecule in inducing alternative activation of macrophages. Our results indicate a great value for research of helminth-derived immunoregulatory molecules, which might contribute to drug development for immune-related diseases. Keywords: Angiostrongylus cantonensis, exosome-depleted excretory-secretory products, N-linked glycoproteins, macrophage polarization, mechanism
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2021
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Exosome-mediated mRNA delivery for SARS-CoV-2 vaccination
Background In less than a year from its zoonotic entry into the human population, SARS-CoV-2 has infected more than 45 million people, caused 1.2 million deaths, and induced widespread societal disruption. Leading SARS-CoV-2 vaccine candidates immunize with the viral spike protein delivered on viral vectors, encoded by injected mRNAs, or as purified protein. Here we describe a different approach to SARS-CoV-2 vaccine development that uses exosomes to deliver mRNAs that encode antigens from multiple SARS-CoV-2 structural proteins. Approach Exosomes were purified and loaded with mRNAs designed to express (i) an artificial fusion protein, LSNME, that contains portions of the viral spike, nucleocapsid, membrane, and envelope proteins, and (ii) a functional form of spike. The resulting combinatorial vaccine, LSNME/SW1, was injected into thirteen weeks-old, male C57BL/6J mice, followed by interrogation of humoral and cellular immune responses to the SARS-CoV-2 nucleocapsid and spike proteins, as well as hematological and histological analysis to interrogate animals for possible adverse effects. Results Immunized mice developed CD4+, and CD8+ T-cell reactivities that respond to both the SARS-CoV-2 nucelocapsid protein and the SARS-CoV-2 spike protein. These responses were apparent nearly two months after the conclusion of vaccination, as expected for a durable response to vaccination. In addition, the spike-reactive CD4+ T-cells response was associated with elevated expression of interferon gamma, indicative of a Th1 response, and a lesser induction of interleukin 4, a Th2-associated cytokine. Vaccinated mice showed no sign of altered growth, injection-site hypersensitivity, change in white blood cell profiles, or alterations in organ morphology. Consistent with these results, we also detected moderate but sustained anti-nucleocapsid and anti-spike antibodies in the plasma of vaccinated animals. Conclusion Taken together, these results validate the use of exosomes for delivering functional mRNAs into target cells in vitro and in vivo, and more specifically, establish that the LSNME/SW1 vaccine induced broad immunity to multiple SARS-CoV-2 proteins. Competing Interest Statement S.J.G is a paid consultant for Capricor, holds equity in Capricor, and is co-inventor of intellectual property licensed by Capricor. S.J.T. is co-inventor of intellectual property licensed by Capricor. C.G. is co-inventor of intellectual property licensed by Capricor. N.A. is an employee of Capricor.
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2021
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Exosomes for Wound Treatment: Purification Optimization, Bioactive Components Identification and Drug Loading
The application of exosomes as therapeutic agents and drug delivery systems has gained increasing popularity over the last decades owing to their natural functions in intercellular communication processes. Exosomes are nanosized membrane vesicles of endosomal origin, which are constitutively released by cells into the extracellular space. They consist of functional proteins, nucleic acids and lipids, which enable them to imitate the biological functions of their producing parent cells. While proteins and nucleic acids have been identified as key players in the biological activity of exosomes, potential contributions of constitutional lipids to these effects remain largely unknown. Moreover, the purification process of exosomes continues to be a critical issue in exosome research since the definition of standardized exosome purification conditions is still pending. Several isolation methods are currently available, yet their potential impact on the exosome functionality has been rarely assessed in sufficient detail. Finally, when investigated as drug delivery platforms, mostly hydrophobic drugs have been loaded into exosomes, therefore leaving the loading capacity of current processes for hydrophilic classical drugs largely unaddressed. Furthermore, the impact of the loading methods on the exosome integrity and intrinsic bioactivity remains incompletely understood as the vesicle characterization is often restricted to analyzing their basic physicochemical properties and cellular uptake as well as monitoring the drug response. This thesis is aimed at addressing central questions related to the characterization of stem cell-derived exosomes as therapeutic entities and drug carriers, mainly in the context of wound healing. The major objectives specifically encompass 1) the optimization of exosome production and purification parameters, and an investigation of their effect on the exosome properties, 2) the identification of the role of selected exosomal components in processes required for wound healing, and 3) a comprehensive appraisal of the impact of several drug loading methods on the exosome integrity and functionality. Chapter 1 introduces the research field of exosomes and presents currently available purification methods. Moreover, the therapeutic applications of stem cell-derived exosomes are portrayed, focusing on their potential use in wound healing. Chapter 2 presents a synopsis of currently available synthetic carriers and exosomes as drug delivery platforms. In addition, drug encapsulation techniques for exosomes are presented and discussed. In Chapter 3, a standardized exosome preparation protocol is described. Special attention was paid to the interplay between production/purification conditions and exosome 2 characteristics to ultimately establish the optimal conditions delivering a high yield of bioactive exosomes. Subsequently, the activity of stem cell-derived exosomes in skin wound healing was assessed both in vitro and in vivo. The potential involvement of the transmembrane enzyme CD73 and exosomal lipids in the wound healing-promoting effects of stem cell exosomes was reported. It was found that the extent of the different exosome components’ activities was dependent on the target cell type. Specifically, CD73 contributed significantly to the in vitro migratory/mitogenic activity of stem cell exosomes on keratinocytes, but had no effect on endothelial cells. Exosomal lipids, on the other hand, were involved in the in vitro and in vivo activity of stem cell exosomes in blood vessel formation and maturation, but did not promote proliferation/migration of keratinocytes or fibroblasts in vitro. Chapter 4 explores processes for the encapsulation of non-membrane permeable hydrophilic low molecular weight compounds (i.e. pyranine and pentoxifylline) into exosomes. The loading efficiency of several methods was compared, and the osmotic shock procedure was identified as the most efficient one. Subsequently, the potential impact of the loading processes on the functionality of stem cell-derived exosomes was assessed using physicochemical characterization and biological activity methods. Only two out of five tested encapsulation processes (i.e. freeze-thawing and osmotic shock) preserved the structural and biological integrity of stem cell exosomes. In Chapter 5, the main findings of the current work are recapitulated and discussed. In addition, an outlook on yet unsolved challenges in the exosome research area is provided.
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2021
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Exosomes released by imatinib‑resistant K562 cells contain specific membrane markers, IFITM3, CD146 and CD36 and increase the survival of imatinib‑sensitive cells in the presence of imatinib
Chronic myeloid leukemia (CML) is a malignant hematopoietic disorder distinguished by the presence of a BCR‑ABL1 fused oncogene with constitutive kinase activity. Targeted CML therapy by specific tyrosine kinase inhibitors (TKIs) leads to a marked improvement in the survival of the patients and their quality of life. However, the development of resistance to TKIs remains a critical issue for a subset of patients. The most common cause of resistance are numerous point mutations in the BCR‑ABL1 gene, followed by less common mutations and multiple mutation-independent mechanisms. Recently, exosomes, which are extracellular vesicles excreted from normal and tumor cells, have been associated with drug resistance and cancer progression. The aim of the present study was to characterize the exosomes released by imatinib‑resistant K562 (K562IR) cells. The K562IR‑derived exosomes were internalized by imatinib‑sensitive K562 cells, which thereby increased their survival in the presence of 2 µM imatinib. The exosomal cargo was subsequently analyzed to identify resistance‑associated markers using a deep label‑free quantification proteomic analysis. There were >3,000 exosomal proteins identified of which, 35 were found to be differentially expressed. From this, a total of 3, namely the membrane proteins, interferon‑induced transmembrane protein 3, CD146 and CD36, were markedly upregulated in the exosomes derived from the K562IR cells, and exhibited surface localization. The upregulation of these proteins was verified in the K562IR exosomes, and also in the K562IR cells. Using flow cytometric analysis, it was possible to further demonstrate the potential of CD146 as a cell surface marker associated with imatinib resistance in K562 cells. Taken together, these results suggested that exosomes and their respective candidate surface proteins could be potential diagnostic markers of TKI drug resistance in CML therapy.
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2021
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Exosomes‐mediated transfer of long noncoding RNA LINC01133 represses bladder cancer progression via regulating the Wnt signaling pathway
Bladder cancer (BC), as one of the most common malignant cancers of the urinary system, has a high incidence and mortality rates. Recently, increasing studies have indicated that exosomes can mediate cellular communication in assorted cancers, including BC. Long noncoding RNAs (lncRNAs) have also been confirmed to take part in the regulation of many cancers. Long intergenic non-protein coding RNA 1133 (LINC01133) is an lncRNA and its roles in several cancers have been revealed. However, the functions of exosomes and LINC01133 in BC are still not elucidated. In our research, functional assays were conducted to evaluate the function of LINC01133, as well as the influence of exosomes and LINC01133 on BC cells. Western blot assay, immunofluorescence assay, electron microscope, and nanoparticle tracking analysis were applied for detecting the characteristics of exosomes. Bioinformatics tools and quantitative reverse-transcription polymerase chain reaction were performed to test the expression of LINC01133 in BC cells and exosomes of the immortalized human uroepithelial cell line (SV-HUC-1). Luciferase reporter assay was performed to measure the activity of the Wnt pathway. We discovered that LINC01133 expression was high in exosomes of SV-HUC-1 and low in that of BC cells. Additionally, exosomes restrained cell viability, proliferation, migration, and invasion. Similarly, LINC01133 exerted the same function on BC cells. In addition, the Wnt signaling pathway could be inactivated by LINC01133. Finally, in vivo experiments demonstrated that cell growth could be suppressed by overexpressed LINC01133. In short, exosomes-mediated transfer of lncRNA LINC01133 repressed BC progression via regulating the Wnt signaling pathway.
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2021
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