Enhancing epithelial regeneration with gelatin methacryloyl hydrogel loaded with extracellular vesicles derived from adipose mesenchymal stem cells for decellularized tracheal patching.

Patch tracheoplasty offers an alternative approach to repairing congenital tracheal stenosis without tension but poses a higher risk of restenosis, granulation tissue formation, and tracheal collapse. The use of tissue-engineered patches for tracheoplasty has been proposed as a solution. Studies suggest that decellularization methods are effective in preparing tracheal patches; however, further research is necessary to improve their efficiency and safety. This study introduces a novel decellularization method using 3-[(3Cholamidopropyl)dimethylammonio]propanesulfonate (CHAPS) and DNase to create a biocompatible tracheal matrix. To enhance the regeneration of epithelial regions within decellularized tracheal scaffolds, this study conducted experimental validations at various levels, both in vivo and in vitro, by introducing extracellular vesicles derived from adipose mesenchymal stem cells as an intervention measure. The ability to promote epithelial regeneration was validated both in vitro and in vivo by incorporating a GelMA hydrogel loaded with adipose-derived mesenchymal stem cell extracellular vesicles (ADMSC-EVs). Evaluation of HBE cell proliferation on tracheal patches treated with varying concentrations of ADMSC-EVs, along with migration and invasion experiments on ADMSC-EV-treated HBE cells, demonstrated enhanced epithelialization in vitro. The inflammatory response and vascular regeneration were assessed via subcutaneous implantation in rats for two weeks. In a rabbit tracheal defect model, the hydrogel loaded with ADMSC-EVs accelerated re-epithelialization in the patch area. This approach shows promise as a novel material for tracheal patching in clinical applications.