Qian Zhiyong, Bai Yating, Zhou Jin, Li Linhao, Na Jing, Fan Yubo, Guo Ximin, Liu Haifeng

A moisturizing chitosan-silk fibroin dressing with silver nanoparticles-adsorbed exosomes for repairing infected wounds

Extracellular Vesicles
/References

Refractory wounds caused by microbial infection impede wound healing, vascular regeneration, nerve system repair and the regeneration of other skin appendages. In addition, large-area infected wounds cause the appearance of multidrug-resistant (MDR) bacterial strains, which pose a major challenge both in clinical and scientific research. Although many stem cell-derived exosomes have been demonstrated to promote skin repair and regeneration, exosomes are seldom applied in the treatment of infective wounds due to the lack of antimicrobial function. In this study, we fabricated an asymmetric wettable dressing with a composite of exosomes and silver nanoparticles (CTS-SF/SA/Ag-Exo dressing) for promoting angiogenesis, nerve repair and infected wound healing. The CTS-SF/SA/Ag-Exo dressing possesses multifunctional properties including broad-spectrum antimicrobial activity, promoting wound healing, retaining moisture and maintaining electrolyte balance. It can effectively inhibit the growth of bacterial and promote the proliferation of human fibroblasts in vitro. Moreover, the in vivo results show that the CTS-SF/SA/Ag-Exo dressing enhanced wound healing by accelerating collagen deposition, angiogenesis and nerve repair in a P. aeruginosa infected mouse skin wound defect model. We hope that this dressing will provide a solution for the repair of infected wounds for treatments in the clinic.

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Background Previous studies found that cigarette smoke (CS) exposure could induce NSCLC malignancy and miRNA dysregulation. Yet, the association of CS-induced miRNA dysregulation and NSCLC malignancy has not been clearly understood. This study aimed to evaluate the effect of CS exposure in smokers on the expression of miR-10b-5p and miR-320b in extracellular vesicles (EVs) from NSCLC patients. Material and methods Bioinformatic analysis was conducted to validate miRNA candidates. Blood and tissue samples were collected from NSCLC patients (n = 21) with smoking and non-smoking history. EVs were isolated from plasma and miRNAs were extracted from the isolated EVs. The miRNAs relative expression was analyzed and compared. Results In silico analysis identified miR-320b and miR-10b-5p as potential biomarkers for diagnosing NSCLC in smokers. Experimental analysis revealed differential expression of EVs-associated miRNAs in NSCLC patients with smoking and non-smoking histories. EVs-associated miR-10b-5p was significantly overexpressed in smoker NSCLC patients (p = 0.000), while miR-320b expression was significantly lower in this group (p = 0.018). Additionally, smoking intensity influenced miRNA expression, with higher smoking intensity correlating with increased miR-10b-5p expression and decreased miR-320b expression. ROC analysis demonstrated that EVs were a superior source of miRNAs compared to plasma for NSCLC diagnostics. miR-10b-5p and miR-320b in EVs showed higher diagnostic performance (AUC 0.878; 0.739) compared to plasma (AUC 0.628; 0.559). Conclusion CS exposure induces different expression of miR-10b-5p and miR-320b in EVs of NSCLC patients with smoking history. EV-related miR-10b-5p and miR-320b showed potential to be utilized as prognostic biomarker for smokers NSCLC patients.

2025

Extracellular vesicles (EVs) have emerged as promising therapeutics with broad clinical applications as diagnostic biomarkers and therapeutic drug delivery systems. Yet, these biopharmaceuticals pose a challenge in terms of manufacturing due to their complexity and heterogeneity. Despite advancements in the field, current purification technologies lack scalability and/or selectivity. Affinity chromatography (AC) − coupling unmatched specificity and scalability − could be used to simplify purification processing and generate clinical-grade EVs with higher titers and purity. In the present work, we report the implementation of an immuno-AC resin to capture and purify EVs directly from clarified cellular feedstocks. Firstly, to guide and support marker selection, vesicle phenotype characterization was conducted using single particle interferometric reflectance image sensing (SP-IRIS) coupled with immunofluorescence. CD81 was the marker which shown to be more present and more likely to have the other markers (CD63 and CD9). Thus, anti-CD81 VHH ligand was generated and evaluated towards recombinant CD81 protein and CD81 bearing EV particles using surface plasmon resonance (SPR). Different chromatographic studies with Anti-CD81 ligand immobilized onto agarose beads resin were conducted to optimize the process parameters (residence time, dynamic binding capacity and impurity clearance). At residence time of 2 min, on average 40 % of pure triple tetraspanin-positive EV fraction was recovered. The enrichment in EV particles herein obtained, based on scale-up calculations, it would be possible to produce 1 × 1013 EVs from a 1L cell culture, while meeting impurity requirements in a single-step purification process (impurity removal over 2 log reduction value). A single-step purification process is possible, enabling the successful isolation of homogeneous EVs population, counting with a final HCP titer of 60 ng/mL and 9 ng/mL of dsDNA impurities. EV’s morphological integrity and internalization ability were also demonstrated, showcasing elution’s efficiency under mild conditions. Overall, this work contributes to the development of a novel, highly specific, AC technology using a camelid-derived affinity ligand which, bridging the scalability requirements demanded of large-scale production, could potentiate the advent of EV-based therapies.

2025

Extracellular vesicles (EVs) have emerged as promising therapeutics with broad clinical applications as diagnostic biomarkers and therapeutic drug delivery systems. Yet, these biopharmaceuticals pose a challenge in terms of manufacturing due to their complexity and heterogeneity. Despite advancements in the field, current purification technologies lack scalability and/or selectivity. Affinity chromatography (AC) − coupling unmatched specificity and scalability − could be used to simplify purification processing and generate clinical-grade EVs with higher titers and purity. In the present work, we report the implementation of an immuno-AC resin to capture and purify EVs directly from clarified cellular feedstocks. Firstly, to guide and support marker selection, vesicle phenotype characterization was conducted using single particle interferometric reflectance image sensing (SP-IRIS) coupled with immunofluorescence. CD81 was the marker which shown to be more present and more likely to have the other markers (CD63 and CD9). Thus, anti-CD81 VHH ligand was generated and evaluated towards recombinant CD81 protein and CD81 bearing EV particles using surface plasmon resonance (SPR). Different chromatographic studies with Anti-CD81 ligand immobilized onto agarose beads resin were conducted to optimize the process parameters (residence time, dynamic binding capacity and impurity clearance). At residence time of 2 min, on average 40 % of pure triple tetraspanin-positive EV fraction was recovered. The enrichment in EV particles herein obtained, based on scale-up calculations, it would be possible to produce 1 × 1013 EVs from a 1L cell culture, while meeting impurity requirements in a single-step purification process (impurity removal over 2 log reduction value). A single-step purification process is possible, enabling the successful isolation of homogeneous EVs population, counting with a final HCP titer of 60 ng/mL and 9 ng/mL of dsDNA impurities. EV’s morphological integrity and internalization ability were also demonstrated, showcasing elution’s efficiency under mild conditions. Overall, this work contributes to the development of a novel, highly specific, AC technology using a camelid-derived affinity ligand which, bridging the scalability requirements demanded of large-scale production, could potentiate the advent of EV-based therapies.

2025
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