Structure and Function of Human Pemphigus Autoantibodies

人天疱疮自身抗体的结构和功能

• 批准号: 8901389
• 负责人: Aimee S Payne
• 金额: $ 40万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8901389
• 关键词: Adhesions; Affect; Affinity; Allergic; Amino Acid Sequence; Amino Acids; Antibodies; Antibody Formation; Antibody Repertoire; Antigens; Autoantibodies; Autoimmune Diseases; Autoimmune Responses; Autoimmunity; B-Cell Development; B-Lymphocytes; Binding; Biological Assay; Bone Marrow; Bulla; Categories; Cell Adhesion Molecules; Chronic; Chronic Disease; Cloning; Consensus; Data; Development; Disease; Epitope Mapping; Epitopes; Event; Functional disorder; Genes; Goals; HIV; HIV Infections; Health; Human; IgG1; IgG4; Immunoglobulin Class Switching; Immunoglobulin Constant Region; Immunoglobulin G; Immunoglobulin Idiotypes; Immunoglobulin Somatic Hypermutation; Immunoglobulin Switch Recombination; Immunoglobulin Variable Region; Individual; Infection; Influenza; Knowledge; Lead; Mature B-Lymphocyte; Mediating; Molecular; Mucous Membrane; Mutate; Mutation; Pathogenicity; Patients; Pattern; Pemphigus; Pemphigus Vulgaris; Peripheral; Peripheral Blood Lymphocyte; Phage Display; Population; Process; Proteins; Rotavirus; Safety; Serum; Skin; Somatic Mutation; Specificity; Structure; Technology; Testing; United States; V(D)J Recombination; Viral Antigens; Virus Diseases; autoreactivity; constant region gene; cross reactivity; desensitization; design; desmoglein; desmoglein III; improved; mouse model; novel strategies; treatment strategy; vaccination strategy

DESCRIPTION (provided by applicant): Autoimmunity is the third most common category of disease in the United States, affecting 8% of the population. Antibody (Ab) repertoire cloning is a state-of-the-art technology for characterizing Abs produced from peripheral B cells. Studies of human Ab repertoires after HIV or influenza infection have identified Abs that neutralize infection and how they develop. This knowledge was gained from analysis of the VH genes used, patterns of somatic mutation, epitope mapping, and pathogenicity assays, and may ultimately lead to more effective vaccination strategies. We anticipate that these same advancements can be made, and are greatly needed to improve the safety of therapy, in autoAb-mediated diseases. Pemphigus vulgaris (PV) is a potentially fatal autoimmune disease in which Abs against the skin cell adhesion protein desmoglein (Dsg) 3 cause severe blistering of the skin and mucous membranes. It is an ideal disease for Ab repertoire cloning because the antigen is well defined and the disease relevance of cloned Abs can be directly tested by functional assays. Currently, it is unknown how many different anti-Dsg3 Abs exist within a patient, whether anti-Dsg3 Abs are similar among patients, and how they develop. This information is essential to understand the pathophysiology of disease and design safer treatment strategies. Human Abs contain two major structural domains, the variable and constant regions, whose expression is governed by VH-DH-JH and CH gene segment usage, respectively. Neutralizing Abs after viral infection often demonstrate VH gene restriction (such as VH1-46 for rotavirus and HIV, and VH1-69 for influenza), presumably because a limited number of Ab gene segments are optimal for binding specific antigenic epitopes. IgG4 CH restriction is observed in conditions of chronic antigen stimulation, such as individuals undergoing allergic desensitization and beekeepers. Our preliminary data suggest that VH1-46 and IgG4 are predominant in the PV anti-Dsg3 Ab repertoire, an exciting finding because it indicates that there are common features of the autoimmune response among patients. We hypothesize that anti-Dsg Abs use a restricted set of variable and constant region genes, which reflects common mechanisms of autoimmunity in PV. To test this hypothesis we will clone anti-Dsg Ab repertoires from PV patients to determine if the anti-Dsg Ab response is oligoclonal, VH- and IgG4-restricted, and shared among patients. We will define early and late molecular events in B cell development (including formation of the na�ve repertoire by VDJ recombination, somatic hypermutation, and class switch recombination) that contribute to the formation of autoreactive Abs in PV. The proposed studies will identify how autoimmunity to a disease-relevant antigen in humans occurs and may lead to novel strategies for targeting only the disease-specific Abs, sparing the beneficial Abs that protect from infection.

描述（由适用提供）：自身免疫性是美国第三大常见的疾病类别，影响了8％的人口。抗体（AB）曲目克隆是一种最新技术，用于表征由外周B细胞产生的ABS。对HIV或影响力感染后人类AB曲目的研究已经确定了ABS中和感染及其发展方式。从对所使用的VH基因，体细胞突变模式，表位映射和致病性测定的分析中获得了这些知识，并最终可能导致更有效的疫苗策略。我们预计可以在自动介导的疾病中提高这些相同的进步，并且非常需要提高治疗的安全性。 Pemphigus dulgaris（PV）是一种潜在的致命自身免疫性疾病，其中ABS针对皮肤细胞粘附蛋白脱木蛋白（DSG）3引起皮肤和粘膜的严重泡沫。它是AB曲线克隆的理想疾病，因为抗原的定义很好，并且可以通过功能分析直接测试克隆ABS的疾病相关性。目前，尚不清楚患者中存在多少不同的抗DSG3 ABS，患者中是否相似，以及他们的发展方式。该信息对于了解疾病和设计安全治疗策略的病理生理学至关重要。人类ABS包含两个主要的结构域，分别由VH-DH-JH和CH基因段使用的变量和恒定区域。病毒感染后中和ABS经常表现出VH基因限制（例如，轮状病毒和HIV的VH1-46，以及影响的VH1-69），大概是因为有限数量的AB基因段非常适合结合特定的抗原性表位。在慢性抗原刺激的条件下，例如接受过敏性脱敏的个体和养蜂人。我们的初步数据表明，VH1-46和IgG4在PV抗DSG3 AB曲目中占主导地位，这是一个令人兴奋的发现，因为它表明患者自身免疫反应的共同特征。我们假设抗DSG ABS使用一组受限的可变和恒定区域基因，这反映了PV中自身免疫的常见机制。为了检验这一假设，我们将在PV患者中克隆抗DSG AB曲目，以确定抗DSG AB反应是否为寡聚，VH-和IgG4受限并在患者中共享。我们将定义B细胞发育中的早期和晚分子事件（包括通过VDJ重组形成中殿曲目，体细胞超偏变和类开关重组），这有助于PV中自动反应性ABS的形成。拟议的研究将确定人类中与疾病相关的抗原的自身免疫性如何发生，并可能导致仅靶向疾病特异性ABS的新策略，从而避免了保护免受感染的有益ABS。