IMMUNOPATHOGENESIS OF BULLOUS PEMPHIGOID

大疱性类天疱疮(BP)和妊娠疱疹(HG)是威胁生命的起泡性疾病，其特征是产生针对半染色体蛋白BPl80和BP230的自身抗体，并形成表皮下水泡。这个项目的总体目标是促进我们对这些疾病的免疫病理机制的理解。本提案的主要焦点是验证这样一种假设，即真皮-表皮连接处的破坏是由浸润性炎症细胞释放的溶乳酶引起的。具体目标1和2是进一步剖析中性粒细胞募集和激活的机制(即细胞黏附分子和细胞表面受体的作用)，并探讨嗜酸性粒细胞在真皮下水泡中的可能作用。致病性抗BP180抗体的被动转移实验将在缺乏促炎细胞因子、中性粒细胞迁移相关整合素或激活相关Fc受体的小鼠身上进行。嗜酸性粒细胞的作用将通过耗竭和重建实验来研究。具体目标3旨在确定蛋白水解酶和活性氧化剂在实验性BP和HG中的作用，并验证BPl80降解产物具有趋化性的假设。缺乏这些蛋白水解酶的小鼠将被注射致病免疫球蛋白。BPl80片段的趋化活性将通过体外和体内趋化试验进行测试。具体目的4是利用被动转运实验和药理学方法研究抗炎药物在皮下水泡中的作用和作用机制。具体目的5是开发一种新的系统，直接检测BP和HG患者血清中自身抗体的致病活性。这些自身抗体将被注射到在基底角质形成细胞中表达人BPl80的新生转基因小鼠中。针对人BPl80上特定抗原位点的亲和纯化自身抗体也将用于这一领域(在Viva系统中用于绘制致病表位图)。这些研究的结果将对BP和HG以及其他相关疾病的患者的护理具有深远的临床意义。

Bullous Pemphigoid (BP) and herpes gestationis (HG) are life-threatening blistering diseases that are characterized by the production of autoantibodies directed against the hemidesmosomal proteins, BPl80 and BP230, and by itie formation of subepidermal vesicles. The overall goal of this project is to advance our understanding of the immunopathological mechanisms operating in these diseases. The major focus of the present proposal is to test the hypothesis that the destruction of the dermal-epidermal junction is caused by proleolytic enzymes released from infiltrating inflammatory cells. Specific aims 1 and 2 are to further dissect the mechanism of recruitment and activation of neutrophils (i.e. the role of cell adhesion molecules and cell surface receptors) and investigate the possible role of eosinophils in subepidermal blistering. Passive transfer experiments with pathogenic anti-BP180 IgG will be performed on mice deficient in proinflammatory cytokines, neutrophil migration-related integrins or activation-related Fc receptors. The role of eosinophils will be investigated by depletion and reconstitution experiments. Specific aim 3 is designed to determine the role of proteolytic enzymes and the reactive oxidants in experimental BP and HG and test the hypothesis that degradation products of BPl80 are chemotactic. Mice deficient in these proteinases will be injected with pathogenic IgG. The chemotactic activity of the BPl80 fragments will be tested by in vitro and in vivo chemotaxis assays. Specific aim 4 is to study effects and mechanisms of action of anti-inflammatory drugs in subepidermal blistering using passive transfer experiments and pharmacologic approaches. Specific aim 5 is to develop a novel system to directly test the pathogenic activity of autoantibodies from BP and HG patients' sera. These autoantibodies will be injected into neonatal transgenic mice expressing human BPl80 in the basal keratinocytes. Affinity-purified autoantibodies against specific antigenic sites on human BPl80 will also be used in this in viva system to map the pathogenic epitopes). The results from these studies will have profound clinical implications in the care of patients with BP and HG and other related diseases.