IDENTIFICATION OF BETA CELL AUTOANTIGENS RECOGNIZED BY CD8+ T CELLS

该项目将确定MHC I类限制性β细胞 自身抗原是CD8 T细胞参与 启动IDDM NOD小鼠模型的自身免疫反应。 与大卫·塞雷兹和德里·鲁本皮安合作的研究开始于 杰克逊实验室表明，从胰岛渗入的淋巴细胞 可以在体外培养出患糖尿病的NOD小鼠 胰岛细胞。从大量培养物中建立了CD8克隆(A1-4.4) 它能识别并特异性地杀死β细胞。另外三条线路有 到目前为止已经被隔离，克隆正在建立中。这些克隆人 出现在NOD小鼠自身免疫性胰岛素炎病程的早期 推测是对启动疾病的关键目标起反应的。 该检测系统独立于与已知的 自身抗体。我们建议从沙门氏菌中分离和鉴定多肽。 转化的β细胞的MHC I类分子，这些分子是 这些CTL克隆。通过以下方法确定多肽的序列 微测序和串联质谱学将允许识别 多肽的来源是自身抗原，因此我们可以 识别自身免疫反应所针对的抗原。这个 CD8T细胞和自身抗原的多肽靶点信息 提供了一种理解T细胞破坏机制的方法 β细胞，并可能允许开发对预防有用的试剂 对IDDM的影响。

This project will identify MHC class I restricted beta-cell autoantigens which are the targets of CD8+ T cells involved in the initiation of the autoimmune response in the NOD mouse model of IDDM. Studies begun in collaboration with David Serreze and Derry Roopenian at Jackson Laboratories have shown that infiltrating lymphocytes from islets of NOD mice developing diabetes can be cultivated in vitro when fed on islet cells. A CD8+ clone (A1-4.4)has been established from bulk cultures which recognize and specifically kill beta-cells. Three other lines have been isolated to date and clones are being established. These clones appear early in the course of autoimmune insulitis in the NOD mouse and presumable are reactive to critical targets in initiating the disease. This detection system is independent of biases related to known autoantibodies. We propose to isolate and characterize peptides from the MHC class I molecules of transformed beta-cells which are the targets for these CTL clones. Determining the sequence of the peptides by microsequencing and tandem mass spectrometry will allow identification of the autoantigen from which the peptides are derived, thus allowing us to identify antigens against which the autoimmune reactivity is directed. The information on peptide targets of the CD8+ T cells and the autoantigens provide an approach to understanding the mechanism for T cell destruction of beta-cells, and may allow development of reagents useful for prevention of IDDM.