不同病毒载量慢性乙型肝炎患者树突状细胞B7-H1表达及对免疫功能的影响

The Expression of B7-H1 on Dendritic Cell and its Effects on Immune Functions in Patients with Different HBV DNA Loads

目的:观察慢性乙型肝炎患者外周血树突状细胞表面共刺激分子B7-H1的表达及对免疫功能的影响。方法:检测慢性乙型肝炎患者肝功能、HBV-DNA水平,将患者分为高病毒载量高ALT组(A组)、高病毒载量低ALT组(B组)、低病毒载量组(C组)及正常对照组(D组)。流式细胞术检测各组患者外周血树突状细胞表面HLA-DR、CD80、CD86、CD83、CD1a、B7-H1表达,酶联免疫吸附试验(ELISA)检测DC培养上清液和混合淋巴细胞培养上清液中细胞因子IL-12、IL-10水平。结果:慢性乙肝患者的树突状细胞膜表面分子HLA-DR、CD80、CD86、CD83、CD1a的表达均明显降低(A、B、C组与D组比较分别为42.3±4.9%、46.7±7.0%、52.5±6.3%vs 94.5±3.5%;34.5±5.3%、39.9±6.4%、45.6±5.2%vs 90.6±6.5%;38.2±8.6%、36.1±5.4%、42.5±6.8%vs87.7±5.1%;28.3±6.5%、25.6±3.4%、33.5±4.3%vs 82.6±4.8%;32.3±5.8%、29.3±5.3%、48.3±4.9%vs 68.2±5.2%P<0.05),B7-H1表达水平明显升高(27.48±21.4%、21.83±20.2%、15.43±10.32%vs 4.23±2.2%P<0.05)。B7-H1表达水平与ALT呈正相关,与IL-12水平呈负相关。结论:慢性乙型肝炎患者树突状细胞功能低下,其机制可能与树突状细胞高表达B7-H1有关。B7-H1高表达抑制了淋巴细胞的功能,导致乙型肝炎病毒持续感染。

Objective： To observe the expression of B7-H1 on dendritic cell and its effects on immune functions in patients with chronic hepatitis B. Methods： 60 patients with chronic hepatitis B were enrolled and divided into three groups according to the level of HBV-DNA and ALT. Twenty healthy people were enrolled and served as controls. The expressions of CD80, CD83, CD86, HLA-DR, CDla and B7-H1 on myeloid dendritic cells （mDC） in the peripheral blood were analyzed by flow cytometry. The level ofIL-10, IL-12 in the supernatants of mixed lymphocytes reaction were detected by enzyme linked immunosorbent assay （ELISA）. T-test was used for the statistical analysis. Results： The expressions of CD80, CD83, CD86, HLA-DR, CDla on mDC in CHB patients were significantly lower than those in healthy controls and the B7-H1 expression on mDC were higher than controls. The differences were significant （P〈0.05）. The expression level of B7-H1 was positively correlated with ALT level. Conclusions： The expression of B7-H1 on mDC in CHB patients is higher than those of healthy people and results in immune suppression. It may be one of the reasons for chronic HBV infection.