T细胞凋亡受体和共刺激分子的表达变化与终末期肾功能衰竭患者细胞免疫功能的关系研究

目的：探究终末期肾功能衰竭患者T细胞亚群的凋亡受体CD95分子与共刺激分子CD28、CDl52（CTLA-4）的表达与细胞免疫功能的关系。方法：采用流式细胞术检测外周血T细胞的凋亡受体CD95（Fas）与共刺激分子CD28／CDl52表达。结果：终末期肾功能衰竭患者CD3^＋T细胞和CD4^＋T细胞比例明显高于健康对照组，CD4／CD8比值增加（P=0．008），CD4^＋T细胞和CD8^＋T细胞上CD95分子表达均上调（P=0．001），以CD8^＋T细胞上CD95分子增加更为明显；CD28和CD152分子在不同T细胞亚群上的表达均上调（P〈0．05），然而，CD4^＋T细胞以CD28分子表达增加为主，而CD8^＋T细胞则CD152分子表达增加为主。结论：终末期肾功能衰竭患者的细胞亚群失衡，共刺激分子CD28和CD152表达异常增加，提示T细胞活化与抑制性调节发生紊乱。T细胞亚群上凋亡受体CD95分子表达增加，以CD8^＋T细胞为主，说明终末期肾功能衰竭者淋巴细胞的减少可能通过两种途径——受体配体途径和负性共刺激分子CD152抑制信号途径，其中以CD8^＋T细胞减少为主，造成患者细胞免疫缺陷。

Relationship of apoptosis and costimulators of T lymphocytes with cellular immune function in patients with end-stage renal failure

Objective:To explore the relationship of expressions of apoptotic receptor CD95 and costimulators of CD28/CD152 (CTLA-4) on T lymphocytic subpopulations with cellular immune in patients with end-stage renal failure(ESRF). Methods:To apply flow cytometry to determine expressions of CD95 and CD28/CD152( CTLA-4) on T cell subsets in patients with ESRF. Results:In comparison between patients group and control group,CD3+T cells and CD4+T cells strikingly increase in patients,the ratio of CD4 and CD8 is increasing(P =0.008) expressions of CD95 on both of CD4+ and CD8+T cells are increasing(P = 0. 001) .however,CD95 is expressed more dominantly on CD8+T cells than on CD4+ T cells; expressions of costimulators on T cell subsets are increasing (P < 0.05) ,in which CD4+CD28+T cells and CD8+CD152+T cells are dominant. Conclusion:Imbalanced T lymphocytic subpopulations and the abnormal expressions of CD28/CD152 in patients with ESRF suggest that activated and suppressed regulations of T cells are disturbed,and expressions of CD95 are more dominant on CD8+T cells,which indicates lymphocytes decrease in patients possibly mainly by two pathways--death receptor-ligand pathway and the suppressed signal induced by negative costimulator CD152, so that the striking reduce of CD8+T cells leads to the defect of cellular immune in patients.