AUTOANTIBODY ANALYSIS FOR A BETTER PREDICTION OF IDDM

1型糖尿病（T1 D）是通过针对65 kD同种型的自身抗体（Ab）预测的。 谷氨酸脱羧酶（GAD 65）、IA-2（一种蛋白酪氨酸磷酸酶样分子）和胰岛素。目的是揭示GAD 65，IA-2和胰岛素自身抗体预测T1 D的机制。总体假设是抗体亲合力和表位特异性两者随着个体朝向反映抗原驱动过程的TED进展而成熟。目标是：1.检验GAD 65、IA-2和胰岛素的亚型和同种型自身抗体单独或联合预测胰岛自身免疫进展为T1 D的假设。针对GAD 65、IA-2和胰岛素的特异性亚型和同种型自身抗体将作为T1 D进展或非进展的函数进行分析。2.检验T1 D进展与针对特异性自身抗原表位的自身抗体成熟相关的假设。使用GAD 65/67杂合蛋白和竞争性表位特异性重组Fab的同种型和亚型特异性测定，将检测自身抗体成熟至特异性表位。 作为进展或不进展为T1 D的函数。3.检验T1 D进展与表位特异性自身抗体的亲合力相关的假设。将在重组Fab与GAD 65和胰岛素的独特表位的竞争测定中检查滴度和自身抗体亲和力成熟。自身抗体亲合力和亲和力常数的测量将用于区分T1 D的非进展者和进展者。项目2将与a）项目1合作，研究非进展者、进展者和新发T1 D患者以及与自身抗体特征相关的CD 4 T细胞谱; B）项目3，与1.5型糖尿病受试者相比，新发典型T1 D患者和T细胞增殖为多种胰岛细胞蛋白和细胞因子分泌模式，以及HLA遗传因素在T1 D风险的一般人群受试者中的作用一直持续到胰岛自身免疫和T1 D。核心B将有助于对从产生抗GAD 65、IA 2和胰岛素的单克隆抗体的杂交瘤细胞系克隆的Fab B cDNA进行测序。我们希望发现，自身抗体成熟的措施将预测进展为糖尿病比单纯的自身抗体阳性。

Type 1 diabetes (T1D) is predicted by autoantibodies (Ab) directed against the 65kD isoform of glutamic acid decarboxylase (GAD65), IA-2, -a protein tyrosine phosphatase-like molecule-, and insulin. The objective is to uncover the mechanisms by which GAD65, IA-2, and insulin autoantibodies predict T1D. The overall hypothesis is that both antibody avidity and epitope specificity mature as an individual progresses towards TED reflecting antigen-driven processes. The aims are: 1. To test the hypothesis that subtype and isotype autoantibodies to GAD65, IA-2, and insulin, alone or in combination predict progression from islet autoimmunity to T1D. Specific subtype and isotype autoantibodies against GAD65, IA-2, and insulin will be analyzed as a function of progression or non-progression to T1D. 2. To test the hypothesis that progression to T1D is associated with autoantibody maturation against specific autoantigen epitopes. Using isoform and subtype specific assays with both GAD65/67 hybrid proteins and competing epitope-specific recombinant Fab, autoantibody maturation to specific epitopes will be established as a function of progression or non-progression to T1D. 3. To test the hypothesis that progression to T1D is associated with the avidity of epitope-specific autoantibodies. Titers and autoantibody affinity maturation will be examined in competition assays with recombinant Fab to unique epitopes of GAD65 and insulin. Measures of autoantibody avidity and affinity constants will be used to distinguish non-progressors from progressors to T1D. Project 2 will collaborate with a) Project 1 on non-progressors, progressors and new onset T1D patients and CD4 T cell profiling in relation to the autoantibody characteristics; b) project 3 on new onset classic T1D patients compared to type 1.5 diabetes subjects and T cell proliferation to multiple islet cell proteins and cytokine secretion patterns and c) Project 4 HLA and non-HLA genetic factors in general population subjects of T1D risk followed until islet autoimmunity and T1D. Core B will be instrumental to sequence Fab cDNA cloned from hybridoma cell lines producing monoclonal antibodies to GAD65, IA2, and insulin. We expect to find that autoantibody maturation measures will predict progression to diabetes better than the mere autoantibody-positivity.