Figure 1. Aged MSCs display increased cellular senescence. (A) Representative images of young and aged MSCs under light microscopy, and quantitative analysis of the cell size of young and aged MSCs. (B) Representative images of SA-β-gal staining, and quantitative analysis of SA-β-gal-positive cells among young and aged MSCs. (C) Western blotting and quantitative analysis of p53 and p21 protein expression in young and aged MSCs. (D) Representative images of Ki-67 staining and quantitative analysis of Ki-67-positive cells among young and aged MSCs. (E) Representative images of the wound healing assay and quantitative analysis of the wound recovery rate in young and aged MSCs. Scale bar=100 μm. Data are expressed as the mean±SEM. n=3. **p<0.01; ***p<0.001.