Rowley M J, Mackay I R, Chen Q Y, Knowles W J, Zimmet P Z
Centre for Molecular Biology and Medicine, Monash University, Clayton, Australia.
Diabetes. 1992 Apr;41(4):548-51. doi: 10.2337/diab.41.4.548.
Insulin-dependent diabetes mellitus (IDDM) is marked by circulating antibodies to a 64,000-M(r) islet cell antigen identified as glutamic acid decarboxylase (GAD). We describe a radioimmunoprecipitation assay with GAD isolated from pig brain. The sera tested were from 80 patients with IDDM including 26 with disease of recent onset and 54 with disease of longer duration (3-42 yr), 20 with non-insulin-dependent diabetes mellitus (NIDDM), and 55 nondiabetic subjects. Conventional assays for islet cell cytoplasmic antibodies were performed concurrently. The level of antibody in serum was expressed in units based on percentage reactivity of a standard reference serum. The frequency of antibody to GAD in IDDM was 69% in short-duration cases and 59% in long-duration cases. The latter was substantially higher than the frequency of islet cell cytoplasmic antibody. Antibodies to GAD were elevated (means +/- 3 SD) in 5% NIDDM cases and in none of the nondiabetic subjects. A simple laboratory test with a defined autoantigen has substantial implications for population screening and early diagnosis of IDDM and for better understanding of its pathogenesis.
胰岛素依赖型糖尿病（IDDM）的特征是循环中存在针对一种分子量为64,000的胰岛细胞抗原的抗体，该抗原被鉴定为谷氨酸脱羧酶（GAD）。我们描述了一种用从猪脑分离的GAD进行的放射免疫沉淀试验。检测的血清来自80例IDDM患者，包括26例近期发病患者和54例病程较长（3 - 42年）的患者，20例非胰岛素依赖型糖尿病（NIDDM）患者以及55例非糖尿病受试者。同时进行了胰岛细胞胞浆抗体的常规检测。血清中的抗体水平以基于标准参考血清反应百分比的单位表示。IDDM中针对GAD的抗体频率在病程短的病例中为69%，在病程长的病例中为59%。后者显著高于胰岛细胞胞浆抗体的频率。5%的NIDDM病例中GAD抗体升高（均值±3标准差），非糖尿病受试者中无一例升高。使用确定的自身抗原进行的简单实验室检测对IDDM的人群筛查、早期诊断以及更好地理解其发病机制具有重要意义。
