重症肌无力胸腺提取液蛋白分析及其与AchR-Ab关系的研究

Analysis of Protein in Thymus Extract of Patients with Myasthenia Gravis and Its Correlation with Serum Acetylcholine Receptor Antibodies

为探讨胸腺在重症肌无力发病机制中的作用 ,取重症肌无力患者手术摘除胸腺制备胸腺提取液 ,进行聚丙烯酰胺凝胶电泳 ,并利用细胞培养和细胞增殖试验观察胸腺提取液对正常人外周血单个核细胞增殖的影响 ,同时利用酶联免疫吸附试验测定其血清AchRab的含量。经聚丙烯酰胺凝胶电泳分析发现约 34 %左右的重症肌无力患者胸腺提取液中存在分子量约为 110 0 0的蛋白 ,这些患者的胸腺提取液对外周血淋巴细胞增殖有显著的抑制作用 ,在胸腺摘除后血清AchRab水平也有更显著的下降 ,与胸腺提取液中没有这种蛋白的重症肌无力患者相比有显著差异 (P <0 0 1)。说明部分重症肌无力患者胸腺提取液蛋白成分和生物学活性异常 ,并可能与自身抗体的产生有关。

In order to investigate the role of thymus in the pathogenesis of myasthenia gravis (MG),the thymus extract was prepared from thymus of patients with MG after thymus extraction operation,and the extracted protein was assayed with SDS polyarylamide gel electrophoresis (SDS PAGE) The effects of thymus extract on the proliferation of peripheral blood mononuclear cells (PBMC) were evaluated with MTT assay,and the serum AchR antibodies were evaluated with ELISA It was found that approximately 34% of patients with MG appeared to have an abnormal protein with molecular weight 11000 in their thymus extracts which showed remarkably inhibitory effect on the proliferation of the PHA activated normal human PBMC This inhibitory effect of thymus extract on the prolifration of PBMC was increased obviously and the serum AchR antibodies were decreased after thymectomy in those patients with MG having this abnormal protein in the thymus extracts,and there existed significant difference in comparison with those thymus extract of patients without this protein It suggests that the protein isolated from part of the patients with MG might be relate to the production of autoantibodies