原发性胆汁性肝硬化患者外周血CD4^＋CD25^＋T细胞的定量及其功能分析

目的检测原发性胆汁性肝硬化（PBC）患者外周血CD4^＋CD25^＋免疫调节性T细胞（Tregs）数量及其对T效应细胞（Treps）增殖的抑制作用。方法流式细胞仪定量检测PBC患者及对照组外周血中Tregs细胞百分比。统计无症状期、症状期、肝硬化期3组患者Tregs细胞百分比。免疫磁珠分离Tregs，检测CD62L、T淋巴细胞相关抗原-4（CTLA-4）、糖皮质激素诱导的肿瘤坏死因子受体（GITR）的表达。体外细胞培养，^3H-胸腺嘧啶掺入法测定Tregs对Treps的免疫抑制功能。结果PBC患者外周血CD4^＋T细胞中的Tregs3．63±0．92）％]明显低于健康对照组（7．42±1．09）％，P〈0．01）]。无症状期、症状期、肝硬化期各组Tregs细胞分别为（3．93±0．71）％、（3．64±0．83）％、（3．52±0．95）％，均明显低于健康对照组，但3组之间差异无统计学意义。Tregs细胞高表达CD62L、CTLA-4、GITR分子。PBC患者Treps的体外增殖可以被自身Tregs所抑制，1：1、1：2、1：4、0：1的比例平均抑制率分别为（78．2±4．9）％、（51．6±7．1）％、（21．7±5．6）％、0，健康对照分别为（75．1±5．3）％、（54．5±6．4）％、（27．6±6．3）％、0，两组相比差异无统计学意义。结论PBC患者Tregs数量的降低可能是PBC的致病机制之一。

Quantitation and functional analysis of CD4+ CD25+ T regulatory cells in patients with primary biliary cirrhosis

Objective To determine the percentage of CD4^＋ CD25^＋ T regulatory cells （Tregs） in peripheral blood from patients with primary biliary cirrhosis （ PBC ） and analyze the suppression function of Tregs to T responder cells （Treps）. Methods Tregs were detected in fresh peripheral blood from patients with PBC and controls by flow-cytome-try analysis. The percentages of Tregs of patients with namely symptomless, symptom and liver cirrhosis were analyzed. Tregs were isolated by immunomagnetic beads and the expression of CD62L, cytotoxic T lymphocyte associated antigen-4 （CTLA-4） and glucocorticoid-induced tumor necrosisfactor receptor （GITR） on Tregs was detected. The isolated Tregs was cultured and suppression function was deteeted by ^3H-thymidine experiment. Results The percentages of Tregs in patients with PBC and controls were （3.63±0.92） % and （7.42±1.09） % respectively, which had statistical significance （P 〈 0.01 ）. The percentages of Tregs of patients with namely symptomless, symptom and liver cirrhosis were （3.93±0.71 ） %, （3.64±0.83 ） % and （3.52±0.95） % respectively, which had not statistical significance. The expression of CD62L, CTLA-4 and GITR on Tregs was higher than on Treps. The proliferation of Treps in patients with PBC was suppressed by the autochthonous Tregs. The average percentages of suppression proliferation of different ratios TregsandTreps （1： 1,1：2,1：4,0： 1）inpatients with PBC and controls were （78.2 ±4.9）% vs（75.1±5.3）%, （51.6±7.1）% vs（54.5±6.4）%,（21.7±5.6）% vs（27.6±6.3）%, 0 vs0, which had not statistical significance. Conclusions The change of percentage of Tregs may play an important role in the pathogenesis of PBC.