慢性乙型肝炎肝细胞MHC抗原表达的免疫组化和免疫电镜的研究

IMMUNOHISTOCHEMICAL AND IMMUNOELECTRONMICROSCOPIC STUDY OF MHC ANTIGENS EXPRESSIONON HEPATOCYTES IN CHRONIC HEPATITIS B

应用单克隆抗体和免疫组化技术，对２２例血清ＨＢｅＡｇ阳性的慢性乙型肝炎患者的肝内ＭＨＣ抗原的表达进行了研究。ＭＨＣ－Ⅰ类抗原在２４例ＣＰＨ和１８例ＣＡＨ患者的肝细胞膜上表达。阳性的肝细胞主要分布在碎屑样、桥样和灶性坏死区。ＭＨＣ－Ⅰ类抗原在肝细胞的表达程度和ＣＤ８＋Ｔ淋巴细胞的肝内浸润和肝病变程度有相关关系。免疫电镜显示，表达ＭＨＣ－Ｉ类抗原的肝细胞和穿过血窦的淋巴细胞密切接触。ＭＨＣ－Ⅱ类（ＨＬＡ－ＤＲ）抗原在１１／１８例的ＣＡＨ患者的肝细胞中表达。阳性的肝细胞呈灶性分布，其表达程度低于ＭＨＣ－Ｉ类抗原。上述结果提示，ＭＨＣ抗原在肝细胞的表达可能在乙型肝炎的发病机制中起重要作用。

The intrahepatic MHC antigens expression in 22 patients with serum HBeAg postitivechronic hepatitis B were studied using monoclonal antibodies and ABC immunohistochemicaltechniques. MHC classⅠ(HLA-ABC)antigens were displayed on the plasma membrane ofparenchymal hepatocytes in 2 of 4 CPH patients and in all of 18 CAH patients. The positivehepatocytes were mainly in the areas of piecemeaL necrosis and intralobular focal necrosis.The extent of display of MHC-Ⅰantigens were correlated to the infiltration of CD8-Tlymphocytes and liver cell damage. Immunoelectron microscopy study showed that thepresence of MHC-Ⅰantigens were found on the membrane of hepatocytes and the positivehepatocytes had close contact with lymphocytes which had passed through the sinusoid.Expression of MHC classⅡantigen (DR)on hepatocytes could not be detected in all CPHpatients and were found in 11 of 18 CAH patients. But the DR positive hepatocytes appearedless than the expression of MHC-Ⅰantigens,and were distributed in focal pattern.This studysuggested that the display of MHC antigens may play an important role on the pathogenesisof hepatitis B.