Project 4 - TLR2-mediatecl control of inflammatory arthritis

项目 4 - TLR2 介导炎症性关节炎的控制

• 批准号: 8523931
• 负责人: Karl W Boehme
• 金额: $ 30.1万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8523931
• 关键词: Adjuvant; Affect; Animal Model; Animals; Antigen-Presenting Cells; Antigens; Area; Arkansas; Arthritis; Autoimmune Diseases; Autoimmune Process; B-Lymphocytes; Biochemical; Biological Response Modifier Therapy; Bone Marrow; CD4 Positive T Lymphocytes; Cell Differentiation process; Cells; Chimera organism; Chronic; Collagen Arthritis; Collagen Type II; Data; Dendritic Cells; Development; Disease; Disease Progression; Disease Resistance; Disease remission; Ectopic Expression; Enzyme-Linked Immunosorbent Assay; Event; Flow Cytometry; Freund' s Adjuvant; Future; Goals; Helper-Inducer T-Lymphocyte; Homeostasis; Human; Immune; Immune response; Immune system; Immunization; Immunology; In Vitro; Inflammatory; Inflammatory Response; Interleukin-17; Interleukin-6; Intervention; Lead; Ligands; Longitudinal Studies; Mediating; Medical; Metalloproteases; Modeling; Molecular; Monitor; Mus; Nature; Pathogenesis; Pathway interactions; Patients; Pattern; Phosphopeptides; Phosphoproteins; Play; Population; Process; Production; Property; Protocols documentation; Relative (related person); Research; Resistance; Rheumatoid Arthritis; Role; Science; Signal Transduction; Signaling Molecule; Source; Symptoms; Synovial Cell; T cell response; T-Lymphocyte; Technology; Testing; Tissues; Toll-Like Receptor 2; Toll-like receptors; Tumor Necrosis Factor-alpha; Universities; Viral Tumor Antigens; Wild Type Mouse; bone loss; cell type; chemokine; combat; cytokine; human TNF protein; immunogenic; improved; innovative technologies; lymph nodes; macrophage; microbial; mouse model; mouse toll-like receptor 2; mycobacterial; neutralizing antibody; new technology; new therapeutic target; novel; novel strategies; pathogen; prevent; response

Rheumatoid arthritis (RA) is a debilitating chronic inflammatory disease affecting approximately 1% of the population worldwide. Present understanding of molecular and cellular events involved in RA is limited, though innate immune responses are considered critical to development of chronic joint inflammation and bone loss seen in RA patients. Collagen-induced arthritis (CIA) is one of the most commonly used animal models of RA; better understanding of the immunopathogenesis of CIA has the potential to provide important information on the mechanisms of human RA. The innate immune response is the first-line of defense in which Toll-like receptors (TLRs) recognize distinct pathogen-associated molecular patterns (PAMPs) and exert subsequent immune responses against a variety of pathogens. Indeed, signaling through TLRs on innate immune cells induces the production of critical cytokines responsible for T helper (Th) cell polarization and subsequent adaptive immune responses. Mycobacterial adjuvants used for CIA induction are known to be rich in ligands for these TLRs, particularly TLR2. The overall goal of this project is to better understand the mechanism by which TLR2 contributes to the development of arthritis. During early RA, antigenpresenting cells such as dendritic cells, macrophages, and B cells respond to PAMP-mediated signaling and produce inflammatory cytokines. Clinically, inhibition of these cytokines dramatically improves symptoms and can be effective in preventing RA disease progression. Recently, Th17 cells, which produce the signature cytokine IL-17, have been implicated in the etiopathogenesis of RA. Our preliminary findings show that IL-6 and IL-17 mediate many of the chronic inflammatory changes in CIA including bone loss, and that TLR2- deficient mice (TLR2-K0) are relatively resistant to this process. We hypothesize that TLR2 signaling plays a pivotal role in the immune response activation that triggers CIA pathogenesis leading to joint inflammation and bone loss. We will test this hypothesis via the following Specific Aims: 1) Assess the role of TLR2- dependent induction of IL-17-producing cells in the pathogenesis of CIA using flow cytometry, ImageStream technology, qRT-PCR, and ELISA; 2) Characterize the role of TLR2 expression in synoviocyte responses during the development of CIA; 3) Identify TLR2-dependent phosphoproteins in both bone marrow-derived dendritic cells and synoviocytes (using phosphoproteomics) as a means of identifying host-derived "activators" of CIA. Near term, our study results will broaden understanding of CIA. Long term, studies of this nature will help identify pathways to support development of novel therapies to treat RA.

风湿性关节炎（RA）是一种使人衰弱的慢性炎症性疾病，影响全球约1%的人口。目前对RA中涉及的分子和细胞事件的理解是有限的，尽管先天免疫应答被认为是RA患者中慢性关节炎症和骨丢失发展的关键。胶原诱导性关节炎（CIA）是最常用的类风湿关节炎动物模型之一，深入了解CIA的免疫发病机制将为研究人类类风湿关节炎的发病机制提供重要信息。先天性免疫应答是第一道防线，其中Toll样受体（TLR）识别不同的病原体相关分子模式（PAMP）并对多种病原体施加随后的免疫应答。事实上，通过先天免疫细胞上的TLR的信号传导诱导负责T辅助（Th）细胞极化和随后的适应性免疫应答的关键细胞因子的产生。已知用于CIA诱导的分枝杆菌佐剂富含这些TLR，特别是TLR 2的配体。该项目的总体目标是更好地了解TLR2促进关节炎发展的机制。在早期RA期间，抗原呈递细胞如树突状细胞、巨噬细胞和B细胞响应PAMP介导的信号传导并产生炎性细胞因子。在临床上，抑制这些细胞因子可显著改善症状，并可有效预防RA疾病进展。最近，产生标志性细胞因子IL-17的Th17细胞已被牵连在RA的发病机制中。我们的初步研究结果表明，IL-6和IL-17介导了CIA中的许多慢性炎症变化，包括骨质流失，并且TLR2缺陷小鼠（TLR2-K0）对该过程具有相对抵抗力。我们假设TLR2信号在免疫应答激活中起关键作用，该免疫应答激活触发CIA发病机制，导致关节炎症和骨丢失。我们将通过以下具体目的来验证这一假设：1）使用流式细胞术、ImageStream技术、qRT-PCR和ELISA评估IL-17产生细胞的TLR2依赖性诱导在CIA发病机制中的作用; 2）表征在CIA发展过程中TLR2表达在滑膜细胞反应中的作用; 3）鉴定骨髓来源的树突细胞和滑膜细胞中的TLR 2依赖性磷蛋白（使用磷蛋白质组学）作为鉴定CIA的宿主来源的"激活剂"的手段。从近期来看，我们的研究成果将拓宽对CIA的理解。从长远来看，这种性质的研究将有助于确定支持开发治疗RA的新疗法的途径。