Kishihara M, Nakao Y, Baba Y, Matsukura S, Kuma K, Fujita T
J Clin Endocrinol Metab. 1979 Nov;49(5):706-11. doi: 10.1210/jcem-49-5-706.
In the TSH radioreceptor assay to study the interaction between Graves' immunoglobulins (Ig) and TSH receptors in guinea pig fat cell membranes, Graves' Ig were found to inhibit [125I]TSH binding to fat cell membranes in a dose-dependent manner. Scatchard analysis of [125I]TSH displacement curves by Graves' Ig indicated a single population of the binding sites in fat cell membranes, in contrast to two populations of TSH-binding sites in the membranes. Displacement of [125I]TSH bound to fat cell membranes by both Graves' Ig and unlabeled TSH were time and temperature dependent, with similar dissociation curves, suggesting a specific binding of Graves' Ig to the membrane sites related to the TSH receptor in the fat cells. Such Ig are referred to as fat cell-binding Ig, to be distinguished from the thyroid-stimulating Ig (TSI) detected by TSH radioreceptor assay using human thyroid membranes. Both fat cell-binding Ig and TSI were detected in the sera of a great majority of untreated patients with Graves' disease. A significant correlation was found between both values (r = 0.80; n = 19; P less than 0.001). According to these results, TSI might represent an autoantibody to the membranes associated with the TSH receptor of the target tissues without a strict organ specificity.
在促甲状腺激素（TSH）放射受体分析中，为研究格雷夫斯病免疫球蛋白（Ig）与豚鼠脂肪细胞膜上TSH受体之间的相互作用，发现格雷夫斯病Ig能以剂量依赖方式抑制[125I]TSH与脂肪细胞膜的结合。通过格雷夫斯病Ig对[125I]TSH置换曲线进行的斯卡查德分析表明，脂肪细胞膜上存在单一群体的结合位点，这与细胞膜上存在两个群体的TSH结合位点形成对比。格雷夫斯病Ig和未标记的TSH对结合于脂肪细胞膜的[125I]TSH的置换均呈时间和温度依赖性，且解离曲线相似，这表明格雷夫斯病Ig与脂肪细胞中与TSH受体相关的膜位点存在特异性结合。此类Ig被称为脂肪细胞结合Ig，以区别于使用人甲状腺膜通过TSH放射受体分析检测到的促甲状腺素（TSI）。在绝大多数未经治疗的格雷夫斯病患者血清中均检测到了脂肪细胞结合Ig和TSI。两者的值之间存在显著相关性（r = 0.80；n = 19；P < 0.001）。根据这些结果，TSI可能代表一种针对与靶组织TSH受体相关的膜的自身抗体，且无严格的器官特异性。
