Desmoglein 2 Function in Cell Adhesion and Pemphigus

桥粒芯糖蛋白 2 在细胞粘附和天疱疮中的作用

• 批准号: 6368667
• 负责人: My Georgia Mahoney
• 金额: $ 7.62万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-28 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6368667
• 关键词: age difference; autoantibody; blister; cell adhesion; cell adhesion molecules; cell growth regulation; epithelium; genetically modified animals; immunologic assay /test; intercellular connection; keratinization; laboratory mouse; laboratory rabbit; pemphigus; protein isoforms; skin; western blottings

DESCRIPTION (provided by applicant): Epidermal keratinocytes are held together by intercellular junctions called desmosomes, which are critical for the maintenance of cell-cell adhesion, tissue integrity, and organ function. Desmogleins (Dsg) are the transmembrane adhesive components of the desmosomes. In the epidermis, Dsg2 and Dsg3 are expressed in the proliferative basal keratinocytes while Dsgl is expressed in the upper differentiated cells. There is compelling evidence that desmogleins mediate cell-cell adhesion. In the human autoimmune blistering disease pemphigus, antibodies directed against Dsg1 and Dsg3 induce blister formation in the epidermis and oral mucosa. In mouse, ablation of the Dsg3 gene results in blister formation similar to that observed in pemphigus vulgaris. However, forced expression of Dsg3 in superficial epidermis where Dsg1 is expressed prevents blister formation by pemphigus foliaceus anti-Dsg1 antibodies. These data demonstrate that Dsg1 and Dsg3 play a pivotal role in epithelial cell adhesion and that one desmoglein can compensate the loss of another. The role of Dsg2 in the epidermis remains elusive in part due to its weak expression. The overall goal of this project is to elucidate the function of Dsg2 in cell adhesion in the skin. The following specific aims are proposed: 1) demonstration of pathogenic pemphigus antibodies that recognize unique epitopes on Dsg2, 2) disruption of the normal expression of Dsg2 in the epidermis, and 3) determining whether Dsg2 can compensate for the loss of Dsg1 and Dsg3. To achieve these specific aims, GST-fusion proteins of the extracellular domains of Dsg2,A,ill be used to characterize pemphigus sera by immunoblotting analysis. In addition, affinity purified Dsg2-specific pemphigus antibodies will be tested to determine specificity in relation to Dsg1 and Dsg3. Dsg2-adsorbed pemphigus antibodies will be tested by passive transfer assays for pathogenicity in neonatal mice. The function of Dsg2 in the epidermis will be studied using transgenic mice expressing Dsg2 in the superficial epidermis under control of the involucrin promoter, which has activity in cells undergoing differentiation. Such mice would provide valuable insights into the biological function of Dsg2 in the development of a functional epidermis with respect to cellular proliferation, differentiation, adhesion and bar-her functions. Finally passive transfer studies will be performed with pemphigus IgG to determine if Dsg2 can protect against anti-Dsg1 -and/or anti -Dsg3 -induced cellular acantholysis. To this end, the ultimate goal is to find a means to upregulate Dsg2 in the epidermis as a therapeutic approach to pemphigus.

描述（由申请人提供）：表皮角质形成细胞合在一起 通过称为脱发的细胞间连接体，这对于 维持细胞 - 细胞粘附，组织完整性和器官功能。 脱木蛋白（DSG）是脱胚体的跨膜粘合剂成分。 在表皮中，DSG2和DSG3在增殖基础上表达 角质形成细胞虽然DSGL在上部分化细胞中表达。那里 令人信服的证据表明脱木素介导细胞 - 细胞粘附。在 人类自身免疫性泡沫疾病Pemphigus，针对DSG1的抗体 DSG3在表皮和口服粘膜中诱导水泡形成。在鼠标中， DSG3基因的消融导致泡出色的形成与观察到的相似 在Pemphigus dulgaris中。但是，浅表中的强迫表达DSG3 表达DSG1的表皮可防止启发 叶状抗DSG1抗体。这些数据表明DSG1和DSG3播放 在上皮细胞粘附中的关键作用，一个脱木蛋白可以 补偿另一个人的损失。 DSG2在表皮中的作用仍然存在 难以捉摸的部分原因是它的表达较弱。这个项目的总体目标是 阐明DSG2在皮肤中细胞粘附中的功能。下列 提出了具体目的：1）病原性Pemphigus抗体的演示 识别DSG2上的独特表位，2）正常表达的破坏 表皮中的DSG2，以及3）确定DSG2是否可以补偿 DSG1和DSG3的损失。为了实现这些特定目的，GST融合蛋白 DSG2的细胞外结构域，a，可用于表征Pemphigus 通过免疫印迹分析通过血清。另外，亲和力纯化的DSG2特异性 将测试Pemphigus抗体，以确定与 DSG1和DSG3。 DSG2吸附的Pemphigus抗体将通过被动测试 新生儿小鼠致病性的转移测定法。 DSG2在 将使用表达DSG2的转基因小鼠研究表皮 浅表表皮受到依象蛋白启动子的控制，其具有 在经历分化的细胞中活性。这样的老鼠会提供有价值的 洞悉DSG2在开发中的生物学功能 功能表皮相对于细胞增殖，分化， 粘附和bar骨功能。最后，被动转移研究将是 用pemphigus igG执行以确定DSG2是否可以预防抗DSG1 - 和/或抗-DSG3诱导的细胞acantholysy。为此，最终 目标是找到一种在表皮中上调DSG2作为治疗的方法 Pemphigus的方法。