Sequential Release of Small Extracellular Vesicles from Bilayered Thiolated Alginate/Polyethylene Glycol Diacrylate Hydrogels for Scarless Wound Healing

• DOI: 10.1021/acsnano.0c07714
• Publication Date: 2021-03-16T23:59:25Z
• Authors: Yifan Shen; Guanzhe Xu; Huanxuan Huang; Kaiyang Wang; Hui Wang; Meidong Lang; Hong Gao; Shichang Zhao
• Keywords: Skin repair

Excessive scar formation has adverse physiological and psychological effects on patients; therefore, a therapeutic strategy for rapid wound healing reduced is urgently needed. Herein, bilayered thiolated alginate/PEG diacrylate (BSSPD) hydrogels were fabricated sequential release of small extracellular vesicles (sEVs), which acted in different phases, to achieve scarless healing. The sEVs secreted by bone marrow derived mesenchymal stem cells (B-sEVs) released from the lower layer promote angiogenesis collagen deposition accelerating fibroblast endothelial cell proliferation migration during early inflammation while miR-29b-3p-enriched upper suppressed excessive capillary late maturation phases. In full-thickness skin defect model rats rabbit ears, repair rate, angiogenesis, evaluated at time points after treatment with BSSPD loaded B-sEVs. Interestingly, end phase vivo model, tissues groups treated (SR-sEVs@BSSPD) exhibited more uniform vascular structure distribution, regular arrangement, volume hyperplastic tissue than other groups. Hence, SR-sEVs@BSSPD based phases was successfully designed considerable potential as cell-free therapy