Innate Immune Activation in Autoimmune Myopathy

自身免疫性肌病的先天免疫激活

• 批准号: 9286500
• 负责人: DANA P ASCHERMAN
• 金额: $ 38万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-10 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9286500
• 关键词: Adverse effects; Antigens; Assessment tool; Autoantigens; Autoimmune Process; Autoimmunity; B-Lymphocytes; Binding; Biochemical; Biological Assay; Biopsy Specimen; Cell Death; Cell physiology; Cells; Complex; Development; Disease; Fatty acid glycerol esters; Foundations; Functional Imaging; Functional disorder; General Population; Genetic Transcription; Hand Strength; Histidine-tRNA Ligase; Histologic; Human; Idiopathic Inflammatory Myopathies; Immune; Immune Targeting; Immune signaling; Immunization; Immunize; Impairment; In Vitro; Infiltration; Inflammation; Inflammatory; Injury; Innate Immune Response; Interleukin-1; Intramuscular; Ischemia; Knock-out; Knockout Mice; Laboratories; Link; Luciferases; Lymphocyte; Magnetic Resonance Imaging; Mediating; Modeling; Molecular; Morbidity - disease rate; Mus; Muscle; Muscle Cells; Muscle Weakness; Muscular Dystrophies; Myoblasts; Myopathy; Myositis; Natural Immunity; Organ; Pathogenesis; Pathogenicity; Pathologic; Pathology; Pathway interactions; Peptides; Phenotype; Play; Process; Production; Proteins; Receptor Signaling; Recombinants; Recruitment Activity; Role; Secondary to; Sepsis; Series; Signal Pathway; Signal Transduction; System; T-Cell Activation; T-Cell Receptor; T-Lymphocyte; TLR2 gene; TLR4 gene; TNF gene; Therapeutic; Therapeutic Agents; Therapeutic immunosuppression; Tissues; Toll-like receptors; Transgenic Mice; Trauma; Treatment Efficacy; Tumor Necrosis Factor Receptor; Vascular Endothelium; Work; adaptive immune response; base; cell motility; comparative trial; cytokine; human disease; immune activation; in vivo; insight; mortality; muscle degeneration; myogenesis; novel therapeutics; prevent; receptor-mediated signaling; regenerative; systemic autoimmune disease; targeted treatment; therapeutic target; tool; trafficking; transcription factor

PROJECT SUMMARY/ABSTRACT The idiopathic inflammatory myopathies (IIMs) represent a group of systemic autoimmune disorders in which muscle and extra-muscular organs are targeted for immune-mediated destruction. We have previously established a model of histidyl-tRNA synthetase (HRS)-induced myositis that involves MyD88-dependent innate immune signaling pathways featuring Toll-like receptors 2 and 4 (TLR2, TLR4). Given the prominent role of these TLRs in our model of HRS-induced myositis, we hypothesize that heightened activation of the downstream transcription regulator NF-κB is ultimately responsible for various inflammatory cascades as well as non-immune pathways promoting muscle dysfunction in this system—effectively linking HRS-induced myositis/IIM with other disorders (including muscular dystrophy as well as sepsis- and trauma/ischemia- induced myopathies) in which NF-κB dysregulation contributes to muscle inflammation, muscle degeneration, and impaired regenerative potential. Through a series of in vitro culture systems and in vivo immunization strategies involving knockout mice lacking critical components of MyD88-dependent signaling pathways, we will systematically examine the impact of HRS-induced TLR signaling and NF-κB activation on T cell migration, T cell activation, and muscle weakness. While Specific Aim 1 will focus on HRS-induced changes in T cell function and TLR-mediated activation of vascular endothelium (leading to lymphocytic infiltration of target organs), Specific Aim 2 will define direct and indirect pathways of HRS-induced NF-κB activation in muscle tissue through in vitro myoblast stimulation assays as well as additional immunization studies focusing on correlations between muscle inflammation, NF-κB activation, and in vivo/ex vivo parameters of muscle weakness. Complementary in vivo assessment tools including MRI and the use of NF-κB-luciferase transgenic mice will further define the relationship between HRS-mediated NF-κB activation and muscle dysfunction, providing the foundation for experimental trials of comparative NF-κB inhibition in Specific Aim 3. Collectively, these studies will elucidate the contribution of innate immunity to the pathogenesis of IIM, supplementing more traditional paradigms of antigen-specific, adaptive immune recognition and identifying therapeutic targets that are potentially relevant to a range of human inflammatory muscle diseases.

项目概要/摘要 特发性炎症性肌病（IIM）代表一组系统性自身免疫性疾病，其中 肌肉和肌外器官是免疫介导破坏的目标。我们之前有过 建立了组氨酰-tRNA 合成酶 (HRS) 诱导的肌炎模型，该模型涉及 MyD88 依赖性 以 Toll 样受体 2 和 4（TLR2、TLR4）为特征的先天免疫信号传导通路。鉴于突出的 这些 TLR 在我们的 HRS 诱发的肌炎模型中的作用，我们假设增强的 TLR 激活 下游转录调节因子 NF-κB 也最终负责各种炎症级联反应 作为促进该系统中肌肉功能障碍的非免疫途径——有效地将 HRS 诱导的 肌炎/IIM 合并其他疾病（包括肌营养不良以及败血症和创伤/缺血） 诱发性肌病），其中 NF-κB 失调会导致肌肉炎症、肌肉退化、 和再生潜力受损。通过一系列的体外培养系统和体内免疫 涉及缺乏 MyD88 依赖性信号通路关键成分的基因敲除小鼠的策略，我们 将系统地研究 HRS 诱导的 TLR 信号传导和 NF-κB 激活对 T 细胞迁移的影响， T 细胞激活和肌肉无力。具体目标 1 将重点关注 HRS 诱导的 T 细胞变化 功能和 TLR 介导的血管内皮激活（导致靶标淋巴细胞浸润） 器官），具体目标 2 将定义 HRS 诱导肌肉中 NF-κB 激活的直接和间接途径 通过体外成肌细胞刺激测定以及其他免疫研究重点关注组织 肌肉炎症、NF-κB 激活和肌肉体内/离体参数之间的相关性 弱点。补充体内评估工具，包括 MRI 和 NF-κB-荧光素酶转基因的使用 小鼠将进一步明确 HRS 介导的 NF-κB 激活与肌肉功能障碍之间的关系， 为特定目标 3 中比较 NF-κB 抑制的实验试验提供基础。总的来说， 这些研究将阐明先天免疫对 IIM 发病机制的贡献，补充更多 抗原特异性、适应性免疫识别和识别治疗靶标的传统范例 可能与一系列人类炎症性肌肉疾病相关。