调节性B细胞在特发性视神经炎发病机制中作用的研究

Regulatory B-cells (Bregs) are a novelly discovered B cell subset, which mediate immune tolerance through producing immune regulatory cytokines such as interleukin (IL)-10 or interacting with other immunocytes. The findings of recent studies suggest that Bregs, which suppress deleterious autoimmuno-inflammatory response, possess immune-regulatory properties in pathological processes of multiple sclerosis (MS) or neuromyelitis optica (NMO) and contribute to the recovery of diseases. In addition, there is a difference in the expression of Bregs between MS and NMO patients. Idiopathic optic neuritis (ION) is the most common type of optic neuritis (ON), and is one of the leading causes of rapid vision loss in young people. Since the pathogenesis and prognosis of ION have close relationship with MS or NMO, we propose the hypothesis that Bregs are closely related to the pathogenesis of ION, and we can predict the outcome of ION by monitoring Bregs. To verify this hypothesis, we will detect the frequency and function of Bregs in peripheral blood from ION patients, and that will be analysed and compared with MS or NMO patients and multiple risk factors for theirs realtionships. Our study aims at revealling the value of Bregs in the pathogenesis and prognosis of ION, and lay the foundation of therapeutic approaches targeting Bregs for ION .

调节性B细胞（Bregs）是新发现的一群通过分泌白介素10等抑制性细胞因子或与其他免疫细胞相互作用来介导免疫耐受的B细胞亚群。近年研究表明Bregs在多发性硬化（MS）或视神经脊髓炎（NMO）发病中发挥着免疫负性调节作用，抑制有害的免疫炎症反应，利于病情的恢复；并且Bregs表达在MS和NMO间存在差异。特发性视神经炎（ION）是视神经炎最常见类型，是造成中青年人视力急剧丧失主要原因，ION发生机制和病情转归与MS或NMO密切相关。我们由此提出科学假说：Bregs与ION发病机制间存在着密切关系，检测Bregs可以预测ION转归。为验证该假说，我们采用流式细胞仪技术对ION患者外周血Bregs表达水平及功能进行检测，并与MS和NMO患者及多种高危转化因子进行相关分析，以揭示Bregs在ION发病机制和预测疾病转归上的意义。本研究结果可能为以Bregs为靶点新的ION治疗方法的研究奠定基础。

(一)目的探讨Bregs在特发性视神经炎(ION)发病机制及ION患者IVMP治疗中的作用.方法研究纳入ION患者30例, HC组30例;未使用IVMP治疗的ION患者25例,采集ION组、HC组及未治ION患者治疗前后外周血分离PBMC,流式细胞术检测两组PBMC中Bregs细胞CD19+CD24hiCD27+细胞及CD19intCD27hiCD38hiCD180-细胞比例;检测CD69CD80BAFF-R在Bregs表达百分比.分析各组间差异及其治疗前后有无差异;结果ION组Bregs表达低于HC,CD19intCD27hiCD38hiCD180-细胞表达高于HC; ION组CD69表达低于HC组. ION患者治疗后Bregs,CD19intCD27hiCD38hiCD180-细胞较治疗前降低，CD69治疗后降低;GS患者Bregs占比变化程度高于GR患者,CD19intCD27hiCD38hiCD180-B细胞占比变化高于GR患者,结论ION患者中Bregs受损，CD19intCD27hiCD38hiCD180-细胞可能促进ION的发病；IVMP治疗对患者Bregs,CD19intCD27hiCD38hiCD180-B细胞具有抑制作用.(一)目的进一步探究Bregs及Tregs,Th1、Th17细胞在ION患者IVMP抵抗中作用.方法纳入ION患者45例,于IVMP治疗前后取外周静脉血分离PBMC,流式细胞术检测患者Bregs,CD3+CD4+CD25+CD127-Tregs及CD3+CD4+IFN-ƴ+Th1细胞CD3+CD4+IL-17+Th17细胞比例,检测胞内因子IL-10,IFN-ƴ,IL-17表达水平;ELISA法检测患者外周血AQP4-IgG,MOG-IgG水平,依患者前后视力变化将患者分为激素敏感组(GS)及激素抵抗组(GR),分别比较各组上述细胞及细胞因子表达水平变化;结果AQP4-IgG+患者治疗前Bregs高于MOG-IgG+患者, AQP4-IgG+患者治疗后Bregs较治疗前下降,MOG-IgG+患者治疗后增加,治疗后GS组Th17细胞下降,GR组上升,GR组Th1比例减少;结论MOG-IgG+患者Bregs损伤较AQP4+患者严重,且GS患者Th17细胞对激素更加敏感,Th1及Th17细胞或可作为提示激素敏感性的指标之一.