Toll-Like Receptors Expressed by Synovial Fibroblasts Perpetuate Th1 and Th17 Cell Responses in Rheu

• 作 者: Fanlei Hu Yingni Li Li Zheng Lianjie Shi Honcgjiang Liu Xuewu Zhang Huaqun Zhu Sumei Tang Lei Zhu Liling Xu Yuqin Yang Zhanguo Li
• 机 构: Department of Rheumatology and Immunology, Peking University People's Hospital, Beijing, China
• 出 处: 第七届类风湿关节炎国际论坛
• 发表日期: 2015年4期

　　Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial fibroblast hyperplasia and bone and cartilage erosion.Synovial fibroblast-and T cell-mediated inflammation plays crucial roles in the pathogenesis of RA.However how this inflammation is initiated, propagated, and maintained remains controversial Here, we systemically examined the contribution of toll-like receptors (TLRs) to the inflammatory mediator production as well as Th1 and Th17 cell hyperactivity in RA.Our results show that rheumatoid arthritis synovial fibroblasts (RASF) express a series of TLRs, including TLR2, TLR3, TLR4, and TLR9, with the predominant expression of TLR3.Moreover, the expression levels of these TLRs were higher than those in osteoarthritis synovial fibroblasts (OASF).Ligation of TLR3, as well as TLR2 and TLR4, resulted in vigorous production of inflammatory cytokines, matrix metalloproteinases (MMPs), and vascular endothelial growth factor (VEGF) in RASF, with activation of the NF-Κb, MAPK, and IRF3 pathways.More important, activation of these TLRs expressed by RASF exacerbated inflammatory Th1 and Th17 cell expansion both in cell-cell contact-dependent and inflammatory cytokine-dependent manners, which induced more IFN-γ and IL-17 accumulation.Targeting TLRs may modulate the inflammation in RA and provide new therapeutic strategies for overcoming this persistent disease.