CD8+T细胞通过抑制小胶质细胞抗原提呈对小鼠EAE模型复发期的保护作用  

Protective Effect of CD8+T Cells on Relapse in Mice EAE Model by Inhibiting Microglial Antigen Presentation

作　　者：田会丽 李娜[2] 胡进[1,3] 曹羿堃 周翔鱼 TIAN Huili;LI Na;HU Jin;CAO Yikun;ZHOU Xiangyu(Ningxia Medical University,Yinchuan 750004,China;Shizuishan First People’s Hospital,Shizuishan 753200,China;General Hospital of Ningxia Medical University,Yinchuan 750004,China)

机构地区：[1]宁夏医科大学,银川750004 [2]石嘴山市第一人民医院,石嘴山753200 [3]宁夏医科大学总医院,银川750004

出　　处：《宁夏医科大学学报》2023年第6期565-572,共8页Journal of Ningxia Medical University

基　　金：国家自然科学基金项目(30010505)。

摘　　要：目的探讨CD8+T细胞在小鼠实验性自身免疫性脑脊髓炎(EAE)复发期的部分免疫效应及其作用机制。方法将30只6~8周雌性C57BL/6小鼠随机分为对照组和EAE模型组,每组15只;EAE模型组给予髓鞘少突胶质细胞糖蛋白(MOG35-55)人工被动免疫;免疫当日起进行临床神经功能评分;透射电子显微镜(TEM)观察髓鞘结构变化;流式细胞术检测脾脏T细胞亚群变化;单细胞转录组测序分析中枢神经系统免疫反应表型及相关基因表达差异;微量样本多指标流式(CBA)检测脑组织中细胞因子表达水平;RT-qPCR检测脑组织中主要组织性相容复合物(MHC)分子、Fas、FasL和颗粒酶B基因表达。结果MOG35-55多肽可以成功诱导雌性C57BL/6小鼠EAE缓解—复发模型;EAE模型组小鼠复发期脾脏中T细胞免疫应答较对照组升高(P<0.05);脑组织内出现大量T淋巴细胞浸润,免疫效应以Th1细胞为主;小胶质细胞中MHCⅠ及MHCⅡ类分子基因表达上调(P均<0.05),且诱导表达MHCⅡ类分子的小胶质细胞几乎同时伴随MHCⅠ类分子的共表达,未见MHCⅡ类分子的独立表达;CD8^(+)T细胞杀伤效应相关分子Fas基因、TNF-α基因表达差异均无统计学意义(P均>0.05);颗粒酶B基因表达量增高(P<0.01)。结论CD8+T细胞可能通过颗粒酶B杀伤MHCⅠ类分子和MHCⅡ类分子共表达的小胶质细胞,通过减弱MHCⅡ类分子对CD4^(+)T细胞活化,间接抑制复发期炎性反应,发挥免疫负调节作用。Objective To investigate the partial immune effect and mechanism of CD8+T cells in the relapse of experimental autoimmune encephalomyelitis(EAE)in mice.Methods Thirty female C57BL/6 mice of 6-8 weeks were randomly divided into control group and EAE model group,with 15 mice in each group.The EAE model group was given artificial passive immunization with myelin oligodendrocytes glycoprotein(MOG35-55).Clinical neurological scores were performed from the day of immunization.Transmission electron microscopy(TEM)was used to observe myelin sheath structure changes.The change of spleen T cell subsets was detected by Flow cytometry.Single-cell RNA sequence was used to analyze the differences in immune response phenotype and gene expression in the central nervous system.The expression levels of cytokines in brain tissues were analyzed through Cytometric Bead Array(CBA).RT-qPCR was used to detect the expression of major histocompatibility complex(MHC),Fas,FasL and granzyme B genes in brain tissue.Results MOG35-55 peptide could successfully induce EAE remission-relapse model in female C57BL/6 mice.The immune response of T cells in relapsed spleen in the EAE model group were significantly higher than that in the control group(P<0.05).A large number of T lymphocyte infiltration occurred in brain tissue,and the immune effect was mainly induced by Th1 cells.The gene expression of MHC classⅠand MHC classⅡin microglia was significantly upregulated(P all<0.05),and the microglia that induced the expression of MHC classⅡwere accompanied by the co-expression of MHC classⅠalmost simultaneously,and no independent expression of MHC classⅡmolecules was seen.The expressions of Fas gene and TNF-αgene related to CD8+T cell killing effect were not significantly changed(P all>0.05).The expression of granzyme B gene was significantly increased(P<0.01).Conclusion CD8^(+)T cells may kill microglia co-expressed by MHC classⅠand MHC classⅡby releasing granzyme B,and indirectly inhibit the inflammatory response in the relapse stage by

关 键 词：实验性自身免疫性脑脊髓炎 多发性硬化 CD8+T细胞 

分 类 号：R744.5[医药卫生—神经病学与精神病学]