Rødgaard A, Nielsen F C, Djurup R, Somnier F, Gammeltoft S
Clin Exp Immunol. 1987 Jan;67(1):82-8.
The concentrations of IgG subclass antibodies (Ab) to acetylcholine receptor (AchR) were quantified in 36 patients with myasthenia gravis (MG) treated with pyridostigmine only, and in eight patients who underwent thymectomy, using an IgG subclass-specific immunoprecipitation assay. IgG1, IgG2, IgG3, and IgG4 subclass Ab to AchR were present in 100%, 33%, 64% and 39% of the pyridostigmine-treated patients, respectively. The concentration of IgG1 Ab increased significantly with disease severity as graded by the Osserman-Genkins classification (rs = 0.37, P less than 0.05). IgG1 and IgG3 subclass protein concentrations were significantly higher (P less than 0.0003) in the 36 pyridostigmine-treated MG patients than in 44 age- and sex-matched healthy subjects. Thymectomy induced an appreciable reduction in anti-AchR IgG1 concentration in two patients, whereas six patients showed no changes in Ab to AchR. The results support the hypothesis that binding of anti-AchR IgG1 and IgG3 on AchR in the neuromuscular junction followed by complement-mediated cell lysis or phagocytosis, may play a role in the pathogenesis of MG.
采用IgG亚类特异性免疫沉淀法，对36例仅接受吡啶斯的明治疗的重症肌无力（MG）患者以及8例接受胸腺切除术的患者，测定其抗乙酰胆碱受体（AchR）IgG亚类抗体（Ab）的浓度。在接受吡啶斯的明治疗的患者中，抗AchR的IgG1、IgG2、IgG3和IgG4亚类Ab分别出现在100%、33%、64%和39%的患者中。根据Osserman-Genkins分类法分级，IgG1 Ab的浓度随疾病严重程度显著增加（rs = 0.37，P < 0.05）。36例接受吡啶斯的明治疗的MG患者的IgG1和IgG3亚类蛋白浓度显著高于44例年龄和性别匹配的健康受试者（P < 0.0003）。胸腺切除术使2例患者的抗AchR IgG1浓度明显降低，而6例患者的抗AchR Ab无变化。这些结果支持以下假说：抗AchR IgG1和IgG3在神经肌肉接头处与AchR结合，随后通过补体介导的细胞裂解或吞噬作用，可能在MG的发病机制中起作用。
