Therapeutic effects of granulation tissue-derived cells on combined radiation and skin wound injury. Granulation tissue-derived cells (GTCs), 1 × 106 per mouse in 0.2 ml phosphate-buffered saline (PBS), were injected around the skin wound margins post 6 Gy total body radiation combined skin wound injury. PBS (0.2 ml per mouse) served as control. (A) Representative wounds injected with PBS (control) or GTCs. (B) Wound residual rates of the GTC-treated group and the control group are presented as mean ± standard deviation (n = 6 mice per group). (C) The fibrotic tissue depths were quantified in serial sections in the center of day 15 wounds treated with PBS or GTCs. (D) Results of the fibrotic tissue depths presented as mean ± standard deviation (n = 6). (E) Representative photomicrographs of Sirius Red-stained sections from day 15 wounds injected with PBS or GTCs. (F) Immunostaining for the classical myofibroblast-specific marker alpha smooth muscle actin (α-SMA) of wound sections derived from day 15 wounds injected with PBS or GTCs. Scale bars = 500 μm. d, days; DAPI, 4′,6-diamidino-2-phenylindole. **P <0.01, *P <0.05.