Fas/FasL expression and apoptosis in the human allografted kidney with acute rejection

Objective To investigate the effect of Fas/Fas ligand (FasL) expression and apoptosis in human allografted kidney with acute rejection (AR) and the clinical implication.Methods Paraffin embedded sections from 26 patients with AR of allografted kidney were conducted to examine the apoptosis and Fas/FasL expression by using the terminal deoxynucleotidyl transferase (TdT) mediated dUTP biotin nick end labeling (TUNEL) method and immunohistochemistry respectively.Results The apoptotic cells detected by TUNEL staining and Fas/FasL expression were mainly observed at the tubular epithelia in AR. The apoptotic index and the degree of Fas/FasL expression were in correspondence with the degree of histopathologic damage in AR, and were significantly higher than normal control and stable grafts ( P 0.01 ). Conclusion The apoptosis of tubular epithelia might play an important role in renal allograft lesions induced by AR, and Fas/FasL might participate in acute renal allograft rejection, which are thought to be mainly responsible for induction of apoptosis in AR. Detection of apoptosis by TUNEL might be an important parameter to evaluate the pathological changes and prognosis in the renal allograft.