Vidnes A, Silsand T, Ljosland R, Kapelrud H, Prydz P E
Scand J Clin Lab Invest. 1982 Sep;42(5):431-5. doi: 10.1080/00365518209168109.
A 44-year-old woman, with an earlier history of myxoedema, had stopped taking thyroxine and was found to have both a slightly elevated basal TSH level and an increased TSH response after thyroliberin stimulation. The T4 value was low borderline, and using a radioimmunoassay that separated free and antibody-bound hormone by polyethylene glycol precipitation, the T3 value was found to be less than zero. This last finding was explained by the existence of T3 antibodies in the patient's serum. The antibodies, being of the IgG class, did not bind T4, thyroglobulin or cytoplasmic thyroid antigen. The subclass IgG2, and to a lesser extent IgG1, IgG3 and IgG4, did bind T3. A Scatchard plot gave an antibody avidity constant of 4.28 x 10(8) l/mol and a binding site concentration of 3.8 x 10(-9) mol/l. Radioimmunoassay of total T3, after extraction with ethanol gave a high value. The concentration of free T3 was, however, just above the lower reference limit.
一名44岁女性，既往有黏液性水肿病史，已停用甲状腺素，发现其基础促甲状腺激素（TSH）水平略有升高，且在促甲状腺素释放激素刺激后TSH反应增强。甲状腺素（T4）值略低于临界值，使用通过聚乙二醇沉淀分离游离激素和抗体结合激素的放射免疫分析法，发现三碘甲状腺原氨酸（T3）值小于零。这一结果可通过患者血清中存在T3抗体来解释。这些抗体属于IgG类，不与T4、甲状腺球蛋白或细胞质甲状腺抗原结合。IgG2亚类以及程度较轻的IgG1、IgG3和IgG4亚类确实能与T3结合。Scatchard图得出抗体亲和力常数为4.28×10⁸ l/mol，结合位点浓度为3.8×10⁻⁹ mol/l。用乙醇提取后对总T3进行放射免疫分析得到一个高值。然而，游离T3浓度仅略高于参考下限。
