Fig. 1

Tubule cells from passage 6 exhibit an obvious senescence phenotype. a Primary PTEC was identified by immunofluorescence of CK18. b β-galactosidase staining was performed to detect senescence. Nearly all tubule cells from the passage 6 (P6) group stained positive for β-galactosidase. c Senescence biomarkers including p53, p21, and p16 were detected by Western blot and upregulated in the P6 group compared to P3 cells. d EdU staining results showed that there was lower positive rate in the P6 group than P3 group