Fig 3.

Local injection of MSCs improves skin wound healing without transdifferentiation. (A) Full-thickness biopsies were created on the dorsal surface of mice previously exposed to IR or not, and the effect of intradermal injection of PBS, MSCs or MSCs exposed to 8 Gy IR in vitro (S-MSC), four injection sites per wound (1 × 10⁶ cells total), on wound healing were analysed. Shown are the proportions of wounds over 90% closed at day 13. (B) Absence of colocalization signal between cytokeratin (in red) and MSCs expressing EGFP (in green) in newly formed epithelium collected 11 days after wounding. Cryosections were stained with DAPI (in blue). Scale bar = 250 μm. (C)–(D) Higher magnification images of epidermis and dermis stained as in (B), respectively. Scale bar = 100 μm, 250 μm.