视神经脊髓炎(NMO) 和多发性硬化(MS)是两种经典的原发性炎症性脱髓鞘性疾病。Th17细胞激活在两者的发病机制中有重要意义。新发现的CD4+IL-9+Th9细胞与Th17密切相关，已有基础研究提示Th9同样参与NMO和MS的病理过程。申请者的前期临床研究也发现NMO和MS患者复发期外周血Th9亚群比例显著高于正常对照组，提示NMO和MS活动期的Th9激活。因此，Th9可能是继Th17后另一种在NMO和MS发病机制中发挥重要作用的新型细胞亚群。本课题采用动物模型、外周血Naïve CD4＋T细胞极化培养和患者临床标本检测等多种实验方法；同时进行Th9细胞激活和阻断实验，从正反两方面论证课题假设；并进行Th9细胞和其他CD4+T细胞比例、转录因子蛋白和核酸表达、细胞因子水平等多层次检测，从有机整体、细胞、蛋白、核酸等多个层面反复验证Th9细胞在NMO和MS发病机制中的免疫调节作用。

Neuromyelitis optica (NMO) and multiple sclerosis (MS) are two typical inflammatory demyelinating diseases of the central nervous system (CNS), and share many similarities. Th17 cells have emerged as a key player in the pathogenesis of NMO and MS. CD4+IL-9+Th9 cells are newly discoverd CD4+T cells subtype in recently years, which have a close relationship with Th17 cells. Simultaneously, growing evidence in base research suggests that Th9 cells are involved in the pathogenetic mechanisms of NMO and MS. In our previous study, the percentage of peripheral blood Th17 cells in patients with NMO or MS during relapse was markedly higher than that in the healthy control participants. This result demonstrated that Th9 cells were activated in patients with NMO and MS. Therefore, Th9 may be anther CD4+T cells subtype which are of great significance in the pathogenesis of NMO and MS besides Th17 cells. In the present study, we adopt experimental method such as animal models, cell culture in vitro and clinical sample detection. We also investigate our hypothesis through Th9 cells activation and inhibition. And prove our theory in multistrata including organic whole, cell, protein and nucleic acid.