IL-36β激活JAK/STAT通路对Tfh细胞分化的影响在系统性红斑狼疮致病机制中的作用

SLE is a kind of autoimmune disease, cause serious damage to the reproductive health of women.We found that in patients with SLE, IL-36 beta and IL-36 R expression enhancement and associated with disease activity. However, IL-36 beta signal transmission mechanism by which lead to SLE has not been reported. Tfh cells differentiation play an important role in the development of systemic lupus erythematosus.We hypothesized that IL-36 beta may result in SLE pathogenesis via regulating Tfh cells differentiation. This topic is proposed to separate patients with SLE blood lymphocytes, build the Tfh cells differentiation model, using IL-36 beta and Physiological saline; By using of flow cytometry, iTRAQ combined biological information analysis, immune coprecipitation, chromosome coprecipitation,cytokines chip, Realtime PCR and immunohistochemical techniques. From cells, animal and clinical comprehensive in-depth study on three layers induced IL-36 beta Tfh cells differentiation mechanism and cause of SLE pathogenesis.The results not only can improve the immunological IL-36 beta to regulate the molecular mechanism of Tfh cells differentiation, It will facilitate to comprehensively elucidate the pathogenic mechanism of SLE, play theoretical foundation for Tfh cells targeted therapy in the SLE. Moreover, it is expected to develop new targeted biological agents instead of corticosteroids in the treatment of autoimmune diseases.

SLE严重危害健康，我们既往国金项目研究已证实IL-36β激活JAK/STAT参与SLE发病，而SLE患者存在Tfh细胞分化异常。我们推测IL-36β激活JAK/STAT可导致Tfh细胞分化异常并合成大量自身免疫复合物致SLE发病。本课题拟分离SLE患者血淋巴细胞，构建Tfh细胞分化模型，采用流式细胞术、iTRAQ联合生物信息分析、免疫共沉淀、染色体共沉淀、细胞因子芯片、Realtime PCR、免疫组化等技术。从细胞、动物、临床三个层次上全面深入研究IL-36β激活JAK/STAT对Tfh细胞分化的影响、明确其调控Tfh细胞分化的分子机制、揭示其在SLE致病中的作用。旨在完善IL-36β调控Tfh细胞分化的分子机制，全面阐明SLE致病机制，为Tfh细胞靶向治疗SLE提供实验依据，并有望开发出新的高效靶向生物制剂替代激素治疗自身免疫病。

系统性红斑狼疮（Systemic lupus erythematosus, SLE）是一种病因不明的慢性多系统损害自身免疫性疾病严重危害健康，潜在发病机制包括免疫细胞异常及细胞因子失衡引起大量自身抗体产生、免疫复合物沉积及补体激活。我们既往国金项目研究已证实IL-36β激活JAK/STAT参与SLE发病，而SLE患者存在Tfh细胞分化异常。我们研究发现IL-36β可上调C57小鼠脾单个核细胞中Tfh细胞标记物IL-21、CXCR5、PD-1、BCL-6、ICOS、TLR7、OX40LmRNA的表达及相关炎症因子IL-21、IL-12、IL-23表达；IL-36β可以时间依赖方式上调C57小鼠脾单个核细胞中Tfh细胞关键转录因子及通路蛋白p-JAK2、p-STAT3、BCL-6的表达，下调BCL-6拮抗分子Blimp-1的表达，且激活的BCL-6的表达可被STAT3抑制剂抑制；IL-36β体外诱导刺激C57小鼠、MRL/lpr狼疮鼠脾单个核细胞脾及naiveCD4+T细胞可上调CXCR5+PD-1+Tfh/CD4+T%细胞比率；我们动物实验不仅证实IL-36β尾静脉注射可以使MRL/lpr小鼠脾脏中Tfh细胞升高，Tfh/Tfr比例失衡，从而加重狼疮皮肤损害和肾脏损害而且IL-36Ra尾静脉注射未能通过抑制Tfh分化从而减轻狼疮症状，提示JKA1抑制剂及IL-36Ra有望成为治疗SLE生物制剂。再者我们研究还发现IL-36β可能通过JAK1/STAT1通路促进TLR7、Blimp-1、XBP-1，抑制BCL-6的生成来促进B细胞向浆细胞分化；表明IL-36β能促进TLR7的胞内运输IL-36β能促进B细胞的活化、抑制其凋亡。总之，我们研究从细胞学、动物层面研究了IL-36β在SLE中的致病机制及并采用临床标本层面较好地验证了上述理论，SLE研究及治疗提供了新思路。