HUMAN T CELL REACTIVITY TO GAD AND ITS ROLE IN IDDM

人们对早期临床试验的热情日益高涨 对临床前IDDM患者进行干预以停止或减缓 自体免疫攻击时出现的β细胞功能的下降。 这样的试验产生了对两种表型标记的需求。第一, 需要能够预测谁将发展的标记物 在IDDM发病率较低的普通人群中传播疾病。 这种性质的可靠、特定的标记将允许 必要的干预试验以证明拟议的 治疗方法要减少。第二，在临床干预试验中 糖尿病患者目前考虑的治疗效果主要是 根据患者是否在3-5年内患上糖尿病来确定， 或者更多。还有对代理标记的额外迫切需求。 这将比那更早地反映治疗效果。在这 项目中，我们假设谷氨酸的细胞免疫 脱羧酶(GMD)可能是IDDM进展的重要预测因子。 一种有限稀释法将用于测量T细胞的频率 系列外周血淋巴细胞中对GMD反应的细胞 来自糖尿病前期患者(基于多个标志物的积极定义)和人类白细胞抗原 配对的对照组。GMD T细胞前体将进行频率测试， 多肽特异性和细胞因子(IL-2与IL-4)分泌 纵向的。对GMD表位有反应的T细胞将通过 几种方法，包括一种新的分子方法。最后，TCR的使用情况 在这些克隆中将进行检测，并将进行原位PCR/FACS分析 用于检测携带GMD反应性TCR的T细胞的频率 来自糖尿病前期患者和对照组的系列PBL样本。这些项目的目标是 建立和验证GMD AS细胞免疫检测方法的研究 IDDM进展的新预测工具。 这是一个跨学科糖尿病研究项目的2号项目。AS 这样，它受益于并有助于许多协作和 IDDM发病机制中早期免疫事件的交互研究。为 例如，这个项目将严重依赖于临床核心(A)到 为研究提供具有良好特征的患者材料，并将依赖于 关于鉴定与GMD结合的多肽的其他项目 至DQ3.2(项目1)，优先处理的多肽和 由不同类型的抗原提呈细胞提出(项目#3和 #4)。反过来，该项目将提供重组人GMD和GMD 反应性T细胞到其他项目，并作为试验场 从这些数据中得出的预测和治疗作用 项目。

There is increasing enthusiasm for clinical trials aimed at early intervention in the pre-clinical IDDM patient in order to halt or slow the decline in beta cell function that occurs with autoimmune attack. Such trials generate a need for two kinds of phenotypic markers. First, there is a need for markers that allow prediction of who will develop disease in the general population where the incidence of IDDM is low. Reliable, specific markers of this nature would allow the size of intervention trials necessary to demonstrate the efficacy of proposed therapies to be reduced. Second, in clinical intervention trials of pre- diabetics as currently contemplated, therapeutic efficacy is mainly determined by whether or not the patient becomes diabetic over 3-5 years, or more. There is an additional critical need for surrogate markers. which will reflect therapeutic efficacy sooner than that. In this project, we hypothesize that cellular immunity to glutamic acid decarboxylase (GMD) may be an important predictor of progression to IDDM. A limiting dilution assay will be used to measure the frequencies of T cells reactive to GMD in serial samples of peripheral blood lymphocytes from prediabetics (defined based on multiple marker positively) and HLA matched controls. GMD T cell precursors will tested for their frequency, peptide specificity, and cytokine (IL-2 vs. IL-4) secretion longitudinally. T cells reactive to GMD epitopes will be cloned by several methods including a novel molecular approach. Finally, TCR usage in these clones will be determined and an in situ PCR/FACS assay will be used to measure the frequencies of GMD reactive TCR bearing T cells in the serial PBL samples from prediabetics and controls. The goal of these studies to develop and validate assays for cellular immunity to GMD as new predictive tools for IDDM progression. This is Project #2 of an interdisciplinary diabetes research program. As such it benefits from, and contributes to, a number of collaborative and interactive studies of early immunologic events in IDDM pathogenesis. For example, this project will rely heavily on the clinical core (A) to provide well characterized patient material for study, and will depend on the other projects for the identification of GMD peptides that bind to DQ3.2 (project #1), and peptides preferentially processed and presented by different types of antigen presenting cells (projects #3 and #4). In turn, this project will provide recombinant human GMD and GMD reactive T cells to the other projects and serve as a testing ground for the predictive and therapeutic utility of data derived from those projects.