Figure 4.

MSC-exos rescue G2/M arrest and promote proliferation of TECs in vivo and in vitro. (A) Representative confocal images of Ki-67⁺ and p-H3⁺ cells. Scale bars, 50 µm. (B) The quantification of Ki-67⁺ TECs and the proportion of p-H3⁺ cells/Ki-67⁺ cells (n = 5). (C) The cell cycle distribution of renal tubular cell suspension. (D) The proportion of renal tubular cells in different phases of cell cycle (n = 5). (E) Western blotting analysis of p53, PCNA, CDK1, and Cyclin B1 in kidney tissues (n = 4). (F) Representative optical micrograph of HK-2 cells in H/R and MSC-exos treated group. Scale bars, 25 µm. (G) Quantification of HK-2 cell counts per HPF (magnified 400×) (n = 10). (H) Representative images of Brdu+ cells. Scale bars, 100 µm. (I) Quantification of Brdu⁺ cells per HPF (magnified 400×) (n = 10). (J) The cell cycle distribution of HK-2 cells in different treatments. (K) The percentage of HK-2 cells in different phase of cell cycle (n = 4). (L) Western blotting of p53, CDK1, and Cyclin B1 in HK-2 cells (n = 4). Data are presented as mean ± SD, *p < 0.05, **p < 0.01, ***p < 0.001 vs. sham group or control group, ^#p < 0.05, ^##p < 0.01, ^###p < 0.001, two-tailed independent Student's t-test or one-way ANOVA.