Structure-Function Relationships in the IL-17 Receptor

IL-17 受体的结构-功能关系

• 批准号: 7463535
• 负责人: Sarah L Gaffen
• 金额: $ 34.78万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2013-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7463535
• 关键词: Adverse effects; Animal Model; Anti-Cytokine Therapy; Applications Grants; Arthritis; Attention; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Binding; Biochemical; C-terminal; CCAAT-Enhancer-Binding Proteins; CD4 Positive T Lymphocytes; Candida; Candida albicans; Cell Line; Cells; Colitis; Collagen Arthritis; Complex; Condition; Crohn' s disease; Cytoplasmic Tail; Data; Development; Disease; Drug Design; Etanercept; Etiology; Exhibits; Experimental Autoimmune Encephalomyelitis; Extracellular Domain; Family; Family member; Fibroblasts; Fluorescence Resonance Energy Transfer; Gel Chromatography; Gene Activation; Gene Expression; Glutathione S-Transferase; Goals; Helper-Inducer T-Lymphocyte; Hormones; Host Defense; Hybrids; Immune; Immune system; Immunity; Immunoprecipitation; Individual; Infection; Infectious Agent; Inflammation; Inflammatory; Integral Membrane Protein; Interleukin-1; Interleukin-12; Interleukin-17; Interleukins; Knowledge; Ligand Binding; Ligand Binding Domain; Ligands; Maps; Mass Spectrum Analysis; Mediating; Membrane; Molecular; Molecular Conformation; Molecular and Cellular Biology; Mus; Mycoses; Nature; Opportunistic Infections; Oral; Oral candidiasis; Pathology; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphorylation; Phosphotransferases; Play; Population; Predisposition; Production; Psoriasis; Public Health; RNA Splicing; Reporting; Rheumatoid Arthritis; Role; Signal Pathway; Signal Transduction; Site; Small Interfering RNA; Structure; Structure-Activity Relationship; System; Systemic Lupus Erythematosus; TNF gene; Tail; Tertiary Protein Structure; Th2 Cells; Therapeutic; Toll-like receptors; Tumor Necrosis Factor Receptor; Ursidae Family; Western Blotting; Work; Yeasts; anakinra; base; cytokine; defined contribution; design; extracellular; in vivo; inhibitor/antagonist; member; mouse model; mutant; novel; novel strategies; oral fungal; pathogen; pre-clinical; receptor; size; stoichiometry; thrush (bird); transcription factor

DESCRIPTION (provided by applicant): Drugs that block pro-inflammatory cytokines or their receptors such as Enbrel (a soluble TNF1 receptor) or Anakinra (a soluble IL-1 receptor antagonist) have been highly successful in treating autoimmune and inflammatory diseases such as rheumatoid arthritis (RA). However, many patients fail to respond to these therapies, and thus new approaches are still needed. A compelling new target is interleukin (IL)-17, the founding member of a novel family of inflammatory cytokines. The IL-17 family has strikingly little structural homology to better-known inflammatory cytokines such as TNF1 or IL-12. The IL-17 family has recently received considerable attention, because IL-17 and a close family member IL-17F are the hallmark cytokines of a newly-discovered T helper cell subset, Th17, that is distinct in lineage and function from the classic Th1 and Th2 cell populations. There is mounting evidence that Th17 cells cause pathology in autoimmune disease, including RA, EAE and colitis. IL-17 and IL-17F deliver signals through a ubiquitous, multimeric receptor complex composed of two IL-17 receptor superfamily members, IL-17RA and IL-17RC. Rational drug design requires a detailed understanding of the target molecule or pathway, but very little is known about the molecular nature of the IL-17R complex or its downstream signaling cascades. Therefore, the overall goal of this proposal is to achieve a detailed understanding of structure-function relationships in the IL-17R complex. To achieve this goal, we will probe the structure and function of the extracellular (Aims 1-2) and cytoplasmic domains (Aims 3-4) of individual subunits within the IL-17R complex. Aim 1: We recently reported that IL-17RA, the first known receptor subunit for IL-17, forms a multimeric complex that is pre-assembled in the membrane prior to ligand binding. This finding suggests that IL-17RA contains a pre-ligand binding assembly domain (PLAD), analogous to a similar domain in the TNF receptor superfamily. Building on preliminary data, we will delineate the IL-17RA PLAD in molecular detail (Aim 1A). Importantly, a soluble TNFR-PLAD serves as an effective inhibitor of arthritis in animal models. Therefore, we will evaluate whether an isolated IL-17RA-PLAD has similar pre-clinical potential as an inhibitor of IL-17 in vivo (Aim 1B). Lastly, we will evaluate the consequences of IL-17R blockade on oral thrush, a common opportunistic infection (Aim 1C). Aim 2: The composition of the IL-17R is surprisingly poorly defined. IL-17RC was recently shown to be a vital component of the IL-17R. We will define the stoichiometry of the IL-17R complex (Aim 2A) and evaluate interactions between IL-17RA and IL-17RC with or without ligand (Aim 2B). Aim 3: The mechanisms by which the IL-17R mediates signaling are largely unknown. However, we found that IL-17RA activates C/EBP transcription factors, which are necessary for target gene expression. We recently showed that IL-17 induces rapid phosphorylation of C/EBP2 on at least two sites. Aim 3 will focus on IL-17-induced pathways leading to C/EBP activation, by (i) defining regions in the IL-17RA tail required for activation of C/EBP (Aim 3A), and (ii) identifying kinases involved in C/EBP2 phosphorylation. Aim 4: The role of IL-17RC in signaling is undefined, and we will use our unique systems to define contributions of IL-17RC to signaling (Aim 4). Collectively, we will define the nature of the IL-17R, with the long-term goal of exploiting this knowledge for therapeutic benefit. PUBLIC HEALTH RELEVANCE The etiology of autoimmunity is poorly understood, but recent advances have discovered a secreted immune hormone (cytokine) termed IL-17 that appears to be responsible for causing many of the pathological effects of autoimmune diseases such as rheumatoid arthritis, psoriasis, systemic lupus erythematosis (SLE) and Crohn's disease. However, surprisingly little is known about how IL-17 causes these effects. This grant application is designed to understand the fundamental molecular biology of the cellular receptor for IL-17, which mediates all the effects of this cytokine on its target cells. Moreover, using that information, we aim to design specific blockers of the IL-17 receptor that might ultimately be used therapeutically to treat autoimmune conditions.

描述（由申请人提供）：阻断促炎细胞因子或其受体(如Enbrel（可溶性TNF1受体）或Anakinra（可溶性IL-1受体拮抗剂）的药物在治疗自身免疫性和炎症性疾病（如类风湿关节炎（RA））方面非常成功。然而，许多患者对这些疗法没有反应，因此仍然需要新的方法。一个引人注目的新靶点是白细胞介素(IL)-17，一个新的炎症细胞因子家族的创始成员。IL-17家族与众所周知的炎性细胞因子如TNF1或IL-12在结构上几乎没有同源性。IL-17家族最近受到了相当大的关注，因为IL-17和一个密切的家族成员IL-17F是新发现的T辅助细胞亚群Th17的标志性细胞因子，Th17在谱系和功能上与经典的Th1和Th2细胞群不同。越来越多的证据表明，Th17细胞引起自身免疫性疾病的病理，包括RA、EAE和结肠炎。IL-17和IL-17F通过一个无处不在的多聚受体复合物传递信号，该复合物由两个IL-17受体超家族成员IL-17RA和IL-17RC组成。合理的药物设计需要详细了解靶分子或途径，但对IL-17R复合物或其下游信号级联的分子性质知之甚少。因此，本提案的总体目标是详细了解IL-17R复合体的结构-功能关系。为了实现这一目标，我们将探讨IL-17R复合体中单个亚基的胞外结构域（Aims 1-2）和胞质结构域（Aims 3-4）的结构和功能。目的1：我们最近报道了IL-17RA， IL-17的第一个已知受体亚基，形成一个多聚体复合物，在配体结合之前预先组装在膜上。这一发现表明IL-17RA含有一个预配体结合组装结构域（PLAD），类似于TNF受体超家族中的一个类似结构域。在初步数据的基础上，我们将描述IL-17RA PLAD的分子细节（Aim 1A）。重要的是，在动物模型中，可溶性TNFR-PLAD可作为有效的关节炎抑制剂。因此，我们将评估分离的IL-17RA-PLAD是否具有与体内IL-17抑制剂相似的临床前潜力（Aim 1B）。最后，我们将评估IL-17R阻断对鹅口疮（一种常见的机会性感染）的影响（Aim 1C）。目标2:IL-17R的组成令人惊讶地不明确。IL-17RC最近被证明是IL-17R的重要组成部分。我们将定义IL-17R复合物的化学计量学（Aim 2A），并评估IL-17RA和IL-17RC与配体或不配体之间的相互作用（Aim 2B）。目的3:IL-17R介导信号传导的机制在很大程度上是未知的。然而，我们发现IL-17RA激活了C/EBP转录因子，这是靶基因表达所必需的。我们最近发现IL-17至少在两个位点诱导C/EBP2的快速磷酸化。Aim 3将重点关注il -17诱导的导致C/EBP激活的途径，通过(i)定义C/EBP激活所需的IL-17RA尾巴区域（Aim 3A），以及（ii）识别参与C/EBP磷酸化的激酶。目标4:IL-17RC在信号传导中的作用尚不明确，我们将使用我们独特的系统来定义IL-17RC对信号传导的贡献（目标4）。总的来说，我们将定义IL-17R的性质，并以利用这一知识获得治疗效益的长期目标。