Mechanism of Humoral Immune Defects in Autoimmune Polyglandular Syndrome Type 1

自身免疫性多腺体综合征1型体液免疫缺陷的机制

• 批准号: 9304961
• 负责人: Kang Chen
• 金额: $ 19.25万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9304961
• 关键词: Address; Antibodies; Antibody Formation; Antibody Repertoire; Antifungal Agents; Autoantibodies; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Avidity; B-Cell Activation; B-Lymphocytes; Biological Assay; Biology; Candida albicans; Candidiasis; Cell Communication; Cells; Cellular Immunity; Chemicals; Chronic Mucocutaneous Candidiasis; Clinical; Clinical Immunology; Complex; Cutaneous; Data; Defect; Disease; Dot Immunoblotting; Effector Cell; Endocrine Glands; Enzyme-Linked Immunosorbent Assay; Enzymes; Exhibits; Eye; Flow Cytometry; Gastrointestinal tract structure; Generations; Genes; Genetic Transcription; Genomics; German population; Goals; Health; Human; Immune; Immune System Diseases; Immune System and Related Disorders; Immune response; Immunity; Immunoglobulin Class Switching; Immunoglobulin G; Immunoglobulin Somatic Hypermutation; Immunoglobulin Switch Recombination; Immunologic Deficiency Syndromes; Immunologics; Impairment; In Vitro; Infection; Interleukin-17; Knowledge; Lymphoid; Lymphoid Tissue; Measures; Mediating; Methodology; Mission; Modeling; Mus; Mutation; Nuclear Localization Signal; Organ; Pathogenesis; Pathogenicity; Patients; Peripheral; Predisposition; Production; Public Health; Regulation; Research; Role; Side; Skin; Structure of germinal center of lymph node; Syndrome; T cell response; T-Lymphocyte; Testing; Therapeutic; Time; United States National Institutes of Health; Uracil; Work; acquired immunodeficiency; activation-induced cytidine deaminase; autoreactive B cell; autoreactivity; base; burden of illness; chromatin immunoprecipitation; congenital immunodeficiency; cytokine; disability; effective therapy; in vivo; innovation; insight; interleukin-22; loss of function mutation; mouse model; mutant; neutralizing antibody; next generation sequencing; novel; response; therapy development

Project Summary Autoimmune Polyglandular Syndrome type 1 (APS-1) is caused by mutations in the Autoimmune Regulator (Aire) gene, which normally promotes central and peripheral T cell tolerance. APS-1 patients exhibit autoimmune disorders in multiple organs and a predisposition to chronic mucocutaneous candidiasis (CMC). A lack of mechanistic under- standing of the basis of candidiasis and its paradoxical association with autoimmunity hampers effective treatment of APS-1. Patients with candidiasis often have defects in cell-mediated immunity. APS-1 patients produce class- switched IgG autoantibodies against T helper 17 (TH17) cytokines, which may neutralize and impair protective anti- fungal immunity. This highlights humoral immune dysfunction as a potentially important contributing factor to CMC in APS-1. Our long-term goal is to understand the immune dysregulation in autoimmune and immunodeficiency disor- ders and to develop mechanism-guided therapeutic strategies. The objective in this application is to elucidate the mechanism of humoral immune defects in APS-1. Our preliminary studies show that AIRE is expressed specifically in human and mouse germinal center (GC) B cells in secondary lymphoid organs in vivo, and in B cells undergoing antibody diversification in vitro. AIRE deficiency in B cells causes elevated class switch recombination (CSR) and somatic hypermutation (SHM). AIRE suppresses CSR when introduced into AIRE-deficient B cells. AIRE interacts in B cells with activation-induced cytidine deaminase (AID), the enzyme essential for SHM and CSR. Aire‒/‒ mice have aberrant expansion of GC B cell and T cell responses in systemic and mucosal lymphoid tissues. These findings support the central hypothesis that APS-1 involves aberrantly increased antibody maturation caused by B cell- intrinsic defects in AIRE-mediated AID regulation and B cell-extrinsic defects in the selection against autoreactive antibodies due to excessive GC response. Our rationale is that the elucidation of the mechanism of humoral immune defects in APS-1 will prompt more specific treatment of APS-1. The hypothesis will be tested by pursing two specific aims. Employing quantitative real-time PCR, flow cytometry, chromatin immunoprecipitation, genomic uracil dot blot and next-generation sequencing, studies in Aim 1 will determine the abnormalities in antibody maturation and the antibody repertoire in APS-1 and the mechanism by which AIRE regulates AID in B cells. Studies in Aim 2 will use competitive ELISA as well as mouse models of cutaneous Candida albicans infection to determine the role of B cell- intrinsic and -extrinsic AIRE deficiency in APS-1-associated candidiasis. This study proposes innovative and cutting- edge methodologies to test novel and mechanistic hypotheses in APS-1 pathogenesis. The work will have sustained and broad impact on the field of basic and clinical immunology, as it will not only advance the understanding of the disease APS-1 and AID-mediated regulation of antibody maturation, but also offer insights into the enigmas of an increasing number of immunodeficiencies that co-present with autoimmunity, thus paving the way to better treat the- se diseases.

项目摘要 自身免疫性综合征1型（APS-1）是由自身免疫调节器（AIRE）突变引起的 基因，通常促进中央和周围T细胞的耐受性。 APS-1患者暴露了自身免疫性疾病 在多个器官和慢性粘膜念珠菌病（CMC）的易感性中。缺乏机械不足 念珠菌病的基础及其与自身免疫的矛盾关联的有效治疗 APS-1。念珠菌病患者通常在细胞介导的免疫力中缺陷。 APS-1患者会产生类 转换针对T辅助17（Th17）细胞因子的IgG自身抗体，可能中和并损害受保护的抗抗抗体 真菌免疫。这强调了体液免疫功能障碍是对CMC的潜在重要因素 APS-1。我们的长期目标是了解自身免疫和免疫缺陷的免疫调节 制定并制定机制引导理论策略。此应用程序的目的是阐明 APS-1中的体液免疫反应机理。我们的初步研究表明，AIRE是专门表达的 在人体和小鼠生发中心（GC）B细胞中，体内的二次淋巴机构中的B细胞以及正在接受的B细胞中 体外抗体多样化。 B细胞中的AIR缺乏会导致升高的类开关重组（CSR）和 躯体超突变（SHM）。当引入AIRE缺陷的B细胞中时，AIR会抑制CSR。 Aire互动 B细胞具有激活诱导的胞苷脱氨酶（AID），该酶是SHM和CSR必不可少的酶。 aire - / - 小鼠具有 全身和粘膜淋巴组织中GC B细胞和T细胞反应的异常扩展。这些发现 支持中心假设，即APS-1涉及由B细胞引起的抗体成熟的异常增加 AIRE介导的辅助调节中的固有缺陷和反应性的选择中的B细胞缺陷 由于GC反应过多而引起的抗体。我们的理由是阐明体液免疫机制 APS-1中的缺陷将促使对APS-1的更具体处理。该假设将通过追求两个特定的检验 目标。采用定量的实时PCR，流式细胞术，染色质免疫沉淀，基因组尿点印迹 和下一代测序，AIM 1的研究将确定抗体成熟和 APS-1中的抗体库以及AIRE调节B细胞帮助的机制。 AIM 2的研究将使用 竞争性ELISA以及白色念珠菌感染的小鼠模型，以确定B细胞的作用 APS-1相关的念珠菌病中的固有和 - 超支AIRE缺乏。这项研究提出了创新和剪裁 在APS-1发病机理中测试新颖和机械假设的边缘方法。这项工作将持续 并对基本和临床免疫学领域的广泛影响，因为它不仅会提高对 疾病APS-1和AID介导的抗体成熟调节 与自身免疫共同存在的免疫缺陷次数增加，从而为更好地治疗这种治疗铺平了道路 SE疾病。

项目成果

Stress Forces First Lineage Differentiation of Mouse Embryonic Stem Cells; Validation of a High-Throughput Screen for Toxicant Stress.

• DOI: 10.1089/scd.2018.0157
• 发表时间: 2019-01
• 期刊: Stem cells and development
• 影响因子: 4
• 作者: Quanwen Li;E. Louden;Jordan Z Zhou;S. Drewlo;Jing Dai;E. Puscheck;Kang Chen;D. Rappolee