Structure-Function Relationships in the IL-17 Receptor

IL-17 受体的结构-功能关系

• 批准号: 8105688
• 负责人: Sarah L Gaffen
• 金额: $ 2.63万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 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/8105688
• 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; 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; 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; 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; public health relevance; receptor; stoichiometry; 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）：阻断促炎性细胞因子或其受体（例如ENBREL（可溶性TNF1受体）或Anakinra（可溶性IL-1受体拮抗剂）的药物，在治疗自身免疫性疾病和炎症性疾病（例如鼻炎）方面已经非常成功。但是，许多患者无法对这些疗法做出反应，因此仍然需要新的方法。引人注目的新目标是白介素（IL）-17，它是新型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）的结构同源很少。 IL-17家族最近受到了广泛的关注，因为IL-17和一个亲密的家庭成员IL-17F是新发现的T辅助细胞子集的标志性细胞因子Th17，其谱系与经典TH1和TH2细胞群在谱系和功能上不同。有越来越多的证据表明，TH17细胞在自身免疫性疾病中引起病理，包括RA，EAE和结肠炎。 IL-17和IL-17F通过普遍存在的多聚体受体复合物传递信号，由两个IL-17受体超家族成员IL-17RA和IL-17RC组成。理性药物设计需要对靶分子或途径有详细的了解，但是关于IL-17R复合物或其下游信号级联的分子性质知之甚少。因此，该提案的总体目标是对IL-17R复合物中的结构 - 功能关系进行详细的了解。为了实现这一目标，我们将探测IL-17R复合物中各个亚基的细胞外（目标1-2）和细胞质结构域（目标3-4）的结构和功能。 AIM 1：我们最近报道说，IL-17RA是IL-17的第一个已知受体亚基，形成了一种多聚体络合物，在配体结合之前预组装在膜上。这一发现表明，IL-17RA包含一个前配体结合结构域（PLAD），类似于TNF受体超家族中的类似结构域。在初步数据的基础上，我们将以分子细节（AIM 1A）描述IL-17RA plad。重要的是，可溶性TNFR-Plad是动物模型中关节炎的有效抑制剂。因此，我们将评估孤立的IL-17RA-PLAD是否具有与体内IL-17的抑制剂相似的临床前潜力（AIM 1B）。最后，我们将评估IL-17R封锁对口服鹅口疮的后果，这是一种常见的机会性感染（AIM 1C）。 AIM 2：IL-17R的组成的定义较差。 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（AIM 2A）的化学计量法，并使用或不使用配体的IL-17RA和IL-17RC之间的相互作用（AIM 2B）。 AIM 3：IL-17R介导信号传导的机制在很大程度上未知。但是，我们发现IL-17RA激活了靶基因表达所必需的C/EBP转录因子。我们最近表明，IL-17至少在两个位点诱导C/EBP2的快速磷酸化。 AIM 3通过（i）定义激活C/EBP（AIM 3A）所需的IL-17RA尾巴中的区域（II）（II）识别参与C/EBP2磷酸化的激酶的IL-17RA尾巴中的区域，将重点放在IL-17诱导的途径上，导致C/EBP激活。 AIM 4：IL-17RC在信号传导中的作用是不确定的，我们将使用独特的系统来定义IL-17RC对信号传导的贡献（AIM 4）。总的来说，我们将定义IL-17R的性质，其长期目标是利用这些知识以获得治疗益处。 公共卫生相关性的自身免疫性病因知之甚少，但是最近的进步发现了一种分泌的免疫激素（Cytokine），称为IL-17，该激素似乎是造成自身免疫性疾病的许多病理影响，例如，类风湿性关节炎，牛皮癣，全身性脂肪症和Crothempersosis和Crotheposis和Crothesiss和Crohes sleans and and sle）但是，关于IL-17如何引起这些效果的知之甚少。该赠款的应用旨在了解IL-17细胞受体的基本分子生物学，从而介导该细胞因子对其靶细胞的所有作用。此外，使用这些信息，我们旨在设计IL-17受体的特定阻滞剂，这些阻滞剂最终可以用治疗来治疗自身免疫性疾病。