FUNCTION OF DESMOGLEIN1/PEMPHIGUS FOLIACEUS ANTIGEN

桥粒糖蛋白1/天疱疮叶状体抗原的功能

• 批准号: 2406206
• 负责人: Kathleen Janee Green
• 金额: $ 21.29万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2406206
• 关键词: autoantibody; autoantigens; cadherins; cell adhesion; cell adhesion molecules; clone cells; conformation; fibroblasts; gene expression; human tissue; intercellular connection; keratinocyte; pathologic process; pemphigus; protein sequence; protein structure function; stoichiometry; tissue /cell culture

Patients with the blistering disease pemphigus foliaceus (PF) have circulating autoantibodies whose antigenic target is a transmembrane desmosomal cadherin called desmoglein 1 (Dsg1). It has been hypothesized that PF IgG might directly inhibit cell adhesion by binding to the extracellular domain of Dsg1 antibodies directly cause PF blisters, nor had Dsg1's role in adhesion been investigated. Over the last funding period substantial progress has been made to define specific epitopes against which PF antibodies are directed, to determine that binding of PF antibodies to these epitopes is dependent on their correct conformation and to demonstrate that anti-Dsg1 antibodies are pathogenic in the disease. However, the precise mechanism by which anti-Dsg1 results in acantholysis is not known. Elucidating this process will depend on first understanding how the desmosomal cadherin adhesive complex is assembled, maintained and regulated. Our aims for the next five years are: 1. To define the contribution of Dsg1 and other desmosomal cadherins to cell-cell adhesion in a fibroblast reconstitution system and to test the hypothesis that the cytoskeletal linker, desmoplakin, is required for desmosomal cadherin-mediated adhesion. 2. To establish the organization of the desmosomal cadherin extracellular domains at the adhesive interface of desmosomes by cross-linking keratinocyte cell surface molecules and analyzing cross-links by peptide sequencing. 3. To investigate the basis and biological significance of the unusual 6:1 stoichiometry exhibited by the plakoglobin:Dsg1 complex and whether plakoglobin:Dsg1 interactions are regulated by phosphorylation of the Dsg1 cytoplasmic tail, and 4. To examine the consequences of ectopically expressing Dsg1 or dominant negative plakoglobin mutants on adhesion, stratification and keratinocyte differention in organotypic raft cultures.

患有叶状天疱疮(PF)的患者有 以跨膜为抗原靶点的循环自身抗体 桥粒钙粘附素称为桥粒蛋白1(DSG1)。一直以来 推测PF-IgG可能通过以下途径直接抑制细胞黏附 直接与DSG1抗体的胞外区结合 引起肺泡，DSG1的S在粘连中的作用也没有得到研究 调查过了。在上一个供资期间，取得了重大进展 被用来定义针对PF抗体的特定表位 目的是确定PF抗体与这些细胞的结合 表位依赖于它们的正确构象，并且 证明抗DSG1抗体在疾病中是致病的。 然而，抗DSG1抗体导致 棘层松解症尚不清楚。要阐明这一过程将取决于 初步了解桥粒钙粘附素黏附复合体是如何 被组装、维护和管理。我们未来五年的目标 年份是：1.界定DSG1和其他 成纤维细胞中桥粒钙粘附素对细胞-细胞黏附的影响 重建系统，并检验细胞骨架的假设 桥粒钙粘附素介导的连接物桥粒粘附素是必需的 粘附力。2.建立桥粒的组织结构 钙粘附素胞外区在细胞间黏附界面的表达 角质形成细胞表面分子交联型桥粒 多肽测序分析交联物。3.调查 不寻常的6：1的基础和生物学意义 白蛋白：DSG1复合体和DSG1复合体 白蛋白：DSG1相互作用是否受 DSG1胞质尾部的磷酸化，以及4.检测 异位表达DSG1或显性基因的后果 白蛋白阴性突变体对黏附、层积和 器官型移植物培养中角质形成细胞的分化。