Lühder F, Woltanski K P, Mauch L, Haubruck H, Kohnert K D, Rjasanowski I, Michaelis D, Ziegler M
Gerhardt Katsch Institute of Diabetes Research, University of Greifswald, Germany.
Eur J Endocrinol. 1994 Jun;130(6):575-80. doi: 10.1530/eje.0.1300575.
Autoantibodies (AAb) to glutamate decarboxylase (GAD) occur with a high prevalence in sera of newly diagnosed type I (insulin-dependent) diabetic patients. The aim of this study was to establish a GAD-AAb radioimmunoassay using 125I-labelled GAD65 and to evaluate this assay in a cross-sectional study with newly diagnosed type I diabetic patients (diabetes duration < 6 weeks). Furthermore, subjects at high risk of developing type I diabetes and individuals suffering from other autoimmune diseases were examined in this assay. For GAD-AAb detection, 125I-labelled GAD65 was incubated with 10 microliters of human serum overnight on ice. Thirty of 51 (59%) type I diabetic patients but none of the 54 healthy blood donors tested were found to be positive. A displacement step using 100,000 g supernatant from rat brain containing or not containing GAD showed the specificity of the binding of 125I-GAD65. Concerning the individuals at high risk of developing diabetes. 9/12 (75%) islet cell antibody (ICA)-positive non-diabetic and 4/34 (12%) ICA-negative subjects with metabolic abnormalities were GAD-AAb positive. These results show the association between type I (insulin-dependent) diabetes mellitus and the occurrence of GAD65-AAb, which possibly predicts a risk of developing the disease.
谷氨酸脱羧酶（GAD）自身抗体（AAb）在新诊断的I型（胰岛素依赖型）糖尿病患者血清中具有较高的发生率。本研究的目的是建立一种使用125I标记的GAD65的GAD-AAb放射免疫测定法，并在一项针对新诊断的I型糖尿病患者（病程<6周）的横断面研究中评估该测定法。此外，还对有患I型糖尿病高风险的受试者和患有其他自身免疫性疾病的个体进行了该测定法检测。为检测GAD-AAb，将125I标记的GAD65与10微升人血清在冰上孵育过夜。在检测的51例I型糖尿病患者中有30例（59%）呈阳性，而54例健康献血者均为阴性。使用含有或不含有GAD的大鼠脑100,000g上清液进行的置换步骤显示了125I-GAD65结合的特异性。关于有患糖尿病高风险的个体，9/12（75%）胰岛细胞抗体（ICA）阳性的非糖尿病患者和4/34（12%）有代谢异常的ICA阴性受试者GAD-AAb呈阳性。这些结果表明I型（胰岛素依赖型）糖尿病与GAD65-AAb的出现之间存在关联，这可能预示着患该疾病的风险。
