MOLECULES AND GENES INVOLVED IN TYPE I DIABETES

我们对自身免疫性疾病的免疫学理解的最大差距 疾病是定义抗原的性质，涉及他们的 发病机制尽管抗体和T细胞克隆能够对 自身决定因素的特点是在不同的自身免疫性 疾病，包括糖尿病。到目前为止，很难确定一个 针对每种病理状况的单一主导靶抗原。 研究的最终目的是确定最重要的 环境因素参与了胰岛素依赖型糖尿病的发病机制。我们最近 胰腺浸润性T细胞库的研究 糖尿病患者在胰岛素依赖型糖尿病发病提供了令人信服的证据， “超抗原”作为关键环境因子的可能候选者 参与了胰岛素依赖型糖尿病的发病机制。这一新证据将一系列 从如此不同的领域产生的数据中存在明显的不一致 病毒学遗传学免疫学和流行病学调查人员正在 在进一步研究这一假设方面处于相当有利的地位， 从死亡的病人身上分离出人类胰岛细胞 一个戏剧性的糖尿病发作是提供给他们在一个相对较大的 数量。此外，他们已经产生了61个独立的T细胞， 来自这些胰岛的浸润淋巴细胞的克隆， 开始了他们的性格。最后，现有的各种专业知识 在T细胞克隆领域的团队成员中， 和Vbeta库测试，病毒RNA检测和表征， 人和小鼠抗胰岛单克隆抗体生产、产生和 用特异性抗体筛选cDNA表达文库，和 从杆状病毒系统获得的基因产物的分析，保证 该项目将迅速进行，以实现以下目标 具体目的：a）表征浸润胰腺癌的T细胞， 为了更精确地检测在胰岛素依赖型糖尿病发病时死亡的患者的胰岛， 确定它们在免疫过程中发挥的作用， 胰腺β细胞的破坏这种特性将 包括对来自新鲜组织总mRNA中细胞因子表达的分析 含有浸润性T细胞的分离的胰岛以及来自 T细胞克隆来自这些胰岛。B）确定是否存在 病毒转录物或病毒产物在胰腺细胞中的表达 使用分子策略，包括R-U 5， PCR和通过PCR的mRNA差异显示。（c）确定和 从人胰岛细胞膜中生化分离蛋白质 特异性激活任何T细胞克隆的提取物。最后，d） 从分离的胰腺癌细胞中筛选cDNA表达文库， 从这些胰岛素依赖型糖尿病患者的胰岛，以确定和表征 相关抗原编码基因。这些研究将使更多的 全面了解胰岛素依赖型糖尿病的病因，反过来， 为新的预防或免疫方法提供基础， 这种疾病的治疗。

The largest gap in our understanding of the immunology of autoimmune diseases is defining the nature of the antigen involved in their pathogenesis. Although antibodies and T cell clones able to react against self determinants have been characterized in different autoimmune diseases, including IDDM. It has been difficult thus far to identify a single prevailing target antigen for each pathologic condition.The ultimate aim of the research is to determine the most important environmental factors involved in the pathogenesis of IDDM. Our recent studies on the repertoire of the T cells infiltrating the pancreata of diabetic patients at the onset of IDDM provide compelling evidence for a "superantigen" as a likely candidate for the critical environmental factor involved in the pathogenesis of IDDM. This new evidence unifies a number of apparent inconsistencies in the data generated from such diverse fields as virology, genetics, immunology and epidemiology. The investigators are in a quite favorable position to further investigate this hypothesis since isolated human pancreatic islet cells from patients who died as a result of a dramatic diabetic onset are available to them in a relatively large quantity. Further, they have already generated 61 independent T cell clones derived from the infiltrating lymphocytes from such islets and have begun their characterization. Finally, the variety of expertise available among the members of the team in the areas of T cell cloning, TCR Valpha and Vbeta repertoire testing, viral RNA detection and characterization, human and mouse anti-islet monoclonal antibody production, generation and screening of cDNA expression libraries with specific antibodies, and analysis of gene products obtained from the Baculovirus system, guarantees that this project will quickly proceed to the fulfillment of the following specific aims: a) To characterize the T cells infiltrating the pancreatic islets of patients who died at onset of IDDM in order to more precisely determine the role they play in the immunologic process that results in the destruction of the pancreatic beta cells. This characterization will include an analysis of cytokine expression in total mRNA from freshly isolated islets containing infiltrating T cells as well as in mRNA from the T cell clones derived from these islets. b) To determine the presence of viral transcripts or viral products in the cells of the pancreatic islets from the IDDM patients using molecular strategies, including R-U5 PCR and differential display of mRNAs by PCR. c) To identify and biochemically isolate proteins from human pancreatic islet cell membrane extracts that specifically activate any of the T cell clones. Finally, d) To screen cDNA expression libraries generated from the isolated pancreatic islets from those IDDM patients in order to identify and characterize the relevant antigen-encoding genes. These studies will allow a more comprehensive understanding of the etiology of IDDM which will, in turn, provide the basis for new preventive or immunotherapeutic approaches to the treatment of this disease.