移植肾排异反应中肾小管上皮细胞的表型转化

目的 观察人移植肾肾穿刺标本不同排异反应病变中肾小管上皮细胞表型转化状态，探讨排异反应与肾小管上皮细胞表型转化的相关性。 方法 免疫组织化学SP法检测55例移植肾穿刺不同病变组中肾小管上皮细胞α平滑肌肌动蛋白（α-SMA）的表达。 结果 各组萎缩病变的肾小管上皮细胞均有α-SMA阳性表达，表现为近基底膜处胞质阳性染色，提示出现了表型转化。在无萎缩病变的肾小管中，仍有部分肾小管细胞呈α-SMA阳性染色。7例基本正常病例组均无肾小管上皮细胞的表型转化。28例急性T细胞介导排异 IA级病例组中，1例肾小管上皮细胞α-SMA阳性表达率为25%~50%，3例为10%~25%。14例排异反应IB 级中，1例α-SMA阳性表达率达50%以上，2例25%~50%，2例10%~25%。 结论 随着急性T细胞介导性排异反应加重，肾小管上皮细胞发生表型转化的现象明显增强。

Renal tubular epithelial phenotypic transdifferentiation in renal allograft rejection

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.