肝内IFN-γ及其分泌细胞在乙型慢加急性肝衰竭发病机制中的作用

目的通过研究肝内促炎细胞因子IFN-γ的表达及IFN-γ的分泌细胞——T淋巴细胞的数量，以明确二者在乙型慢加急性肝衰竭（acute—on—chronic liver failure，ACLF）发病机制中的作用。方法采用免疫组化方法，分析乙型ACLF患者、慢性乙型肝炎（乙肝）患者及正常对照组肝内IFN-γ的原位表达以及其分泌细胞CD4^＋T淋巴细胞与CD8^＋T淋巴细胞的数量。结果①乙型ACLF患者IFN-γ阳性分泌细胞数均明显高于慢性乙肝患者及正常对照组，差异有统计学意义（P均〈0．001），慢性乙肝患者IFN-γ阳性分泌细胞数明显高于正常对照组，差异有统计学意义（P〈0．001）；②乙型ACLF患者肝内CD4^＋和CD8^＋T淋巴细胞数量较慢性乙肝及正常对照组明显增加（P均〈0．001），慢性乙肝患者肝内CD4^＋和CD8^＋T淋巴细胞数量较正常对照组明显增加（P均〈0．001）；③肝内IFN-γ阳性分泌细胞数量与CD4＋T淋巴细胞和CD8^＋T淋巴细胞数量均具有明显的相关性（r=-0．896和0．885，P均〈0．001）。结论乙型ACLF患者肝内CD4^＋T淋巴细胞、CD8^＋T淋巴细胞数量的增加，其分泌的IFN-γ的增加可能参与了ACLF的发病过程。

Roles of intrahepatic expression of interferon gamma and expression of its secreting cells in the pathogenesis of HBV-related acute-on-chronic liver failure

Objective To determine the roles of the expression of intrahepatic proinflammatory interferon γ （IFN-γ ） and the number of T cells, which secreted IFN-γ , in the pathogenesis of HBV-related acute-on-chronic liver failure （ACLF）. Methods Immunohistochemistry was used to analyze in situ expressions of IFN- γ and the expression of CD4^＋ and CD8^＋ T lymphocytes in the livers of patients with ACLF, of patients with chronic hepatitis B （CHB） and of normal controls （NC）. Results （1） The number of IFN- γ -positive lymphocytes found in ACLF patients was significantly higher than that found in CHB patients and NC（both P〈 0.001 ）. The number of IFN-γ -positive lymphocytes found in CHB patients was significantly higher than that found in NC （P〈0.001）. （2） HBV-related ACLF patients exhibited a significant increase in the number of CD4^＋and CD8^＋ T lymphocytes compared with CHB and NC groups （all P〈0.001）. The number of CD4^＋ and CD8^＋ T lymphocytes found in CHB patients was also significantly higher than that found in NC （both P〈 0.001）. （3）The number of intrahepatic IFN- γ -positive cells was significantly correlated to the number of CD4^＋ and CD8^＋ T lymphocytes （r = 0.896 and 0.885, respectively, both P〈0.001）. Conclusions The increase in the expression of proinflammatory IFN-γ and the number of CD4^＋ and CD8^＋ T lymphocytes in the livers of patients with HBV-related ACLF may contribute to the pathogenesis of ACLF.