ABSTRACT
Objective To observe the transdifferentiation of renal tubular epithelial phenotype in allograft biopsy samples of patients with various rejections,and to analyze the association between rejection and transdifferentiation.Method Immunohistochemistry (SP method) was applied to detect α-SMA expression in tubular epithelial cells from 55 renal allograft biopsy samples with various rejection.Results Positive α-SMA expression was found in all the atrophic tubular epithelial cells adjacent to cytoplasm of basement membrane,which indicated the atrophic renal tubular epithelial cells appeared the phenotypic transdifferentiation.Positive α-SMA was also detected in some renal epithelial cells without atrophy.No phenotypic change was found in 7 cases without obviously rejection.Among 28 cases of acute T-cell-mediated rejection IA grade,α-SMA positive expression rate of non-atrophy renal epithelial cells was 25％-50％ in 1 case and 10％-25％ in 3 cases.Among 14 cases of more severe acute rejection group IB grade,α-SMA positive expression rate was over 50％ in 1 case,25％-50％ in 2 cases and 10％-25％ in 2 cases.Conclusion When acute T-cell-mediated rejection becomes more serious in renal allograft,the phenotype transdifferentiation aggravates in renal tubular epithelial cells.