原发性胆汁性肝硬化患者共刺激分子B7-H4的检测及临床意义

目的 探讨原发性胆汁性肝硬化(primary biliary cirrhosis,PBC)患者共刺激因子B7-1t4的表达及其与疾病发病机制的关系.方法 分别采用荧光实时定量PCR法(real-time PCR)、酶联免疫吸附试验(ELISA)及流式细胞术(FCM)检测65名PBC患者外周血单个核细胞(PBMC)B7-H4mRNA表达水平、血清IL-2水平以及CD4+、CD8+ T细胞亚群和T细胞表面B7-H4表达百分率,同时监测抗线粒体抗体(anti-mitochondrial antibody,AMA)及临床各项生化指标的关系.结果 (1)PBC患者PBMC B7-144 mRNA水平及T细胞表面B7-H4表达百分率显著低于非PBC肝硬化组及健康对照组(P<0.01).(2)活化72 h后各实验组及对照组IL-2含量及CD4+、CD8+、CD4+ CD8+T淋巴细胞表达水平均低于活化前,以非PBC肝硬化组与健康对照组降低显著(P<0.05);PBC组IL-2含量及CD4+、CD4+ CD8+ T淋巴细胞表达水平高于非PBC肝硬化组与健康对照组(P<0.01).(3)AMA-M2阳性患者血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、碱性磷酸酶(ALP)及γ-谷氨酰转肽酶(GGT)水平升高,其中ALP及GGT升高显著(P<0.05);AMA-M2阳性患者与阴性患者T细胞表面B7-H4表达百分率差异无统计学意义(P>0.05).结论 共刺激因子B7-H4对PBC患者体内T细胞活化增殖及细胞因子分泌的抑制作用减弱,为研究PBC的发生发展和阐明PBC的发病机制提供了试验资料.

Expression of costimulating factor B7-H4 in patients with primary billary cirrhosis

Objective To study the relationship between the expression of eostimulating factor B7-H4 in patients with primary biliary cirrhosis (PBC) and the pathogenesis of PBC. Methods The expression of B7-H4 mRNA on peripheral blood mononuclear cell (PBMC) of 65 patients with PBC was tested by real-time PCR. Serum levels of IL-2 were assayed by ELISA. CD4+, CD8+ T lymphocytes expression level and B7-H4 expression rate before and after activation were measured by three-color flow cytometry (FCM). Re-sults (1) Expression of B7-H4 mRNA and BT-H4 percentage in PBC group were significantly lower than that in none-PBC group and healthy controls(P<0.01);(2)After 72 h activation, the percentage of CD4+, CD8+, and CD4+ CD8+T lymphoeytes and serum levels of IL-2 decreased (P<0.05), and the percentage of CD4+, CD4+ CD8+T lymphocytes and serum levels of IL-2 were significantly higher than that of none-PBC group and healthy controls(P<0.01);(3)Levels of alanine aminotransferase(ALT), aspartate amin-otransferase(AST), alkaline phosphatase(ALP) and γ-glutamyl transpeptidase(GGT) of patients with posi-tive anti-mitochondrial antibody(AMA)-M2 rose. There was no significant difference of B7-H4 expressions on T cells between patients either with or without AMA-M2 antibody. Conclusion The costimulating factor B7-H4 can express on T lymphocytes which is activated by phytohemagglatinin(PHA) aad plays a negative role on T cells responses.