To investigate the physicochemical properties of silk fibroin （SF）-modified sheep acellular dermal matrix （SADM），and the repair effect and mechanism of its composite system with human adipose-derived mesenchymal stem cell （hADSCs） membranes on full-thickness skin defect wounds in mice.

Microporous SADM was prepared by combining pancrease-ribozyme digestion with repeated freeze-thaw. SF-SADM was obtained by impregnation with 5.0% SF solution. Changes in SADM pore structure before and after modification were observed under scanning electron microscopy and porosity was measured. The degradation profiles of SADM before and after modification were evaluated via in vitro degradation experiments. The hADSCs were isolated and cultured from discarded adipose tissue obtained from plastic surgery. Following characterization，the hADSCs were subjected to sheet culture and subsequently co-cultured with SADM and SF-SADM to establish the SADM-hADSCs and SF-SADM-hADSCs composite system. MTS assay were used to compare cell proliferation activity before and after SF modification，fluorescence labeling was used to observe the adhesion of cell membranes to scaffolds，and laser confocal microscopy was used to observe cell migration ability on scaffolds. Thirty-six healthy Kunming mice were selected and approximately 1 cm diameter circular full-thickness skin defect model was established at the mid-dorsal area. The mice were divided into SADM，SADM-hADSCs，and SF-SADM-hADSCs groups，with 12 mice in each group. The wounds in each group were covered with the corresponding membrane. Wound healing，histological changes，and angiogenesis were observed at 3，7，and 14 days postoperatively，and one-way ANOVA and t-test were performed on the data.

After SF modification，SADM porosity was significantly improved （P<0.05）. SF delayed the enzymatic hydrolysis process to some extent，making the degradation more controllable. The cell proliferation activity of SF-SADM-hADSCs was significantly higher than that of SADM-hADSCs （P<0.05）. In vivo healing promoter experiments，the wound healing rate at 14 days after surgery in the SF-SADM-hADSCs group reached 96.3%±2.1%，significantly higher than 72.4%±4.2% in the SADM group and 85.7%±3.5% in the SADM-hADSCs group （P values all <0.05）, with essentially achieved re-epithelialization and good vascularization.

5.0% SF solution can optimize the physicochemical properties of SADM，making it more bioactive. The SF-SADM-hADSCs composite system can accelerate high-quality healing of full-thickness skin defect wounds in mice by promoting re-epithelialization and angiogenesis.