Figure 4. P16 expression in rabbit AFSCs cultured in growth medium with five different conditions for 6 days and stained by immunostaining. (A, F) Growth medium only (Control); (B, G) bleomycin 10 μg/ml (Bleo-10); (C, H) bleomycin 50 μg/ml (Bleo-50). (D, I) Bleomycin 50 μg/ml and rapamycin 25 nM (Bleo-50 + Rapa-25); (E, J) Bleomycin 50 μg/ml and rapamycin 50 nM (Bleo-50 + Rapa-50); (L) Semi-quantification of positive stained AF cells grown in five different concentrations for 6 days. The images of F, G, H, I, J were enlarged areas of the boxes in images of A, B, C, D, E. The results indicated that bleomycin treatment increased the expression of P16 in AF cells which was stained by red fluorescence. Rapamycin decreased P16 expression induced by bleomycin. White bars: 100 μm, Yellow bars: 50 μm. *p<0.05 compared to control, #P<0.05 compared to the cells treated with 50 μg/ml of bleomycin.