Figure 1 Reduced Klotho expression was strongly associated with the progression of chronic allograft dysfunction. Renal allografts derived from the rat renal transplant model were harvested and identified by HE staining (A) and Masson trichrome staining (B). The quantitative analysis of fibrosis area is shown in Figure C. Furthermore, distribution and expression of Klotho were examined by immunohistochemistry staining (D), and quantitative analysis showed significantly reduced Klotho expression in the renal tubular area and the interstitial area (E). Fibronectin expression was tested (F) and quantitative analysis indicated the remarkable expression of fibronectin in the Allo group (G). Finally, the total protein and RNA was extracted and we performed western blotting and RT-PCR to examine the protein and mRNA levels of Klotho (H, I) and fibronectin (H, J). *** P<0.001 compared to control group; **** P<0.0001 compared to control group. Each experiment was performed at least 3 times.