Fig. 9

dMSC-sEVs enhanced diabetic wound healing. a Representative photographs of healing progression from day 0 to day 28. The statistical analysis of wound area in the dMSC-sEVs and PBS groups (n = 5). b, c Representative photographs of scar widths and the statistical analysis of the scar widths (n = 5), scale bar = 1 mm. d Masson’s trichrome staining at day 7 and day 21 post- wounding. The collagen fiber was stained in blue. × 200, scale bar = 500 μm. × 400, scale bar = 200 μm. e Representative immunofluorescence images of PCNA, CXCR4, α-SMA, and p21 staining. Scale bar = 50 μm. *p < 0.05, **p < 0.01, ***p < 0.001