急性MCMV感染对小鼠脾Th1/Th2/Th17细胞亚群分化的影响  

Effects of murine cytomegalovirus infection on the polarization of Th1/Th2/Th17 cells

作　　者：李旭芳[1] 刘玲玲[1] 张菊[1] 廖毅[1] 刘杨[1] 于萌[1] 刘兴楼[1] 李革[1] 舒赛男[1] 方峰[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院儿科临床病毒室,武汉430030

出　　处：《中国免疫学杂志》2013年第5期464-467,473,共5页Chinese Journal of Immunology

基　　金：国家自然科学基金资助项目(No.81271807)

摘　　要：目的:在整体水平观察小鼠巨细胞病毒(MCMV)感染对小鼠脾Th1/Th2/Th17细胞亚群分化及其主要的效应性细胞因子(IFN-γ、IL-4、IL-17A)表达的影响。方法:建立MCMV感染模型,8只BALB/c小鼠分别于接种MCMV Smith株后3天和14天各处死4只;另设8只接种唾液腺匀浆的模拟感染小鼠作为对照。用空斑形成试验测定肝、脾和唾液腺组织病毒滴度;流式细胞术检测脾T淋巴细胞中Th1(CD4+IFN-γ+)、Th2(CD4+IL-4+)、Th17(CD4+IL-17A+)细胞比例,双抗体夹心ELISA法检测脾细胞培养上清中病毒特异性IFN-γ、IL-4、IL-17A水平。结果:MCMV感染早期肝、脾和唾液腺组织中病毒呈低水平复制,而感染后14天仅在唾液腺组织呈高水平复制;Th1细胞比例及病毒特异性IFN-γ主要在MCMV感染早期呈显著升高(P<0.01);Th2细胞及IL-4均无明显表达及改变;Th17细胞及病毒特异性IL-17A则主要在感染后14天升高(P<0.05)。结论:MCMV感染早期,机体通过上调Th1细胞分化比例及IFN-γ的表达发挥抗病毒效应,而MCMV诱导Th17细胞分化及IL-17A的高表达可能是MCMV感染致宿主特异性细胞免疫功能失调并逃避机体特异性细胞免疫攻击的原因之一。Objective：To investigate the possible role of murine cytomegalovirus（MCMV） infection in the polarization of Th1/Th2/Th17 cells and the expression of IFN-γ,IL-4 and IL-17A in vivo.Methods： A BALB/c mice model system with MCMV infection was established.Sixteen mice were randomly divided into MCMV infection group（n=8） and control infection group（n=8）.All experimental mice were sacrificed at 3 and 14 days（n=4 at each time point） after MCMV infection.The titer of MCMV was quantified by standard plaque formation assay.The percentages of Th1（CD4^＋IFN-γ^＋）,Th2（CD4^＋IL-4^＋） and Th17（CD4^＋IL-17A^＋） in T lymphocytes of spleen were measured by flow cytometry.Double antibody sandwich ELISA was employed to detect the levels of IFN-γ,IL-4 and IL-17A in spleen cell culture supernatants.Results： Low levels of MCMV replication were seen in liver,spleen and salivary gland on day 3 after MCMV infection and significantly high level was only seen in salivary gland on day 14.The percentage of Th1 cells and the level of MCMV-specific IFN-γ were mainly increased on day 3 after MCMV infection（P〈0.01）,however,the percentage of Th17 cells and the MCMV-specific IL-17A were mainly increased on day 14（P〈0.05）and no detectable Th2 cells and IL-4 was seen all through the experiments.Conclusion： MCMV infection markedly induced the polarization of Th1 cells and the expression of IFN-γ at early time points and significantly induced the polarization of Th17 cells and the expression of IL-17A on day 14.The increase of Th17 cells and IL-17A are likely to suppression the balance of cellular immunity in the infected host and become one of the leading cause of MCMV to escape the specific cellular immune attack so that persistent of latent infection even disease will occur under certain conditions.

关 键 词：TH1细胞 TH2细胞 Th17细胞 鼠巨细胞病毒 

分 类 号：R392[医药卫生—免疫学]