Project 4 - TLR2-mediatecl control of inflammatory arthritis

项目 4 - TLR2 介导控制炎症性关节炎

• 批准号: 8652487
• 负责人: Karl W Boehme
• 金额: $ 31.19万
• 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/8652487
• 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.

类风湿性关节炎 (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。目前对与 RA 相关的分子和细胞事件的了解有限，尽管先天免疫反应被认为对于 RA 患者出现慢性关节炎症和骨质流失至关重要。胶原诱导性关节炎（CIA）是最常用的 RA 动物模型之一；更好地了解 CIA 的免疫发病机制有可能为人类 RA 的机制提供重要信息。先天免疫反应是第一道防线，其中 Toll 样受体 (TLR) 识别不同的病原体相关分子模式 (PAMP)，并对多种病原体产生后续免疫反应。事实上，先天免疫细胞上的 TLR 信号传导会诱导关键细胞因子的产生，这些细胞因子负责 T 辅助细胞 (Th) 细胞极化和随后的适应性免疫反应。已知用于 CIA 诱导的分枝杆菌佐剂富含这些 TLR，特别是 TLR2 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，树突状细胞、巨噬细胞和 B 细胞等抗原呈递细胞对 PAMP 介导的信号传导作出反应并产生炎症细胞因子。临床上，抑制这些细胞因子可显着改善症状，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 细胞与 RA 的发病机制有关。我们的初步研究结果表明，IL-6 和 IL-17 介导 CIA 的许多慢性炎症变化，包括骨质流失，并且 TLR2 缺陷小鼠 (TLR2-K0) 对这一过程相对有抵抗力。我们假设 TLR2 信号传导在免疫反应激活中发挥关键作用，从而触发 CIA 发病机制，导致关节炎症和骨质流失。我们将通过以下具体目标检验这一假设： 1) 使用流式细胞术、ImageStream 技术、qRT-PCR 和 ELISA 评估 TLR2 依赖性诱导产生 IL-17 的细胞在 CIA 发病机制中的作用； 2）表征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状细胞和滑膜细胞中的 TLR2 依赖性磷酸蛋白（使用磷酸蛋白质组学），作为鉴定宿主来源的 CIA“激活剂”的方法。短期内，我们的研究结果将拓宽对中央情报局的了解。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 新疗法的途径。