重症肌无力合并胸腺瘤的血清学诊断:蛋白印迹法与酶联免疫法的比较

Comparison of Western blotting and ELISA in sera diagnosis of myasthenia gravis with thymoma

目的：探讨Ｗａｓｔｅｒｎｂｌｏｔ法对重症肌无力合并胸腺瘤（ＭＧＴ）患者的血清学诊断价值。方法：分别用蛋白印迹法和酶联免疫法检测３３例重症肌无力患者（有瘤１６例，无瘤１７例）、正常人１０例、其他疾病对照１８例血清中的人骨骼肌柠檬酸提取物抗体（ＣＡＥ－Ａｂ）。结果：ＣＡＥ抗原中３．４万，５．０万，６．０万组分与ＭＧＴ患者血清结合显色率分别为９３．７％（１５／１６例），７５．０％（１２／１６例），７５．０％（１２／１６例），而其他组无１例结合显色。蛋白印迹法、酶联免疫法对ＭＧＴ患者检出阳性率分别为１６／１６，１２／１６，假阳性率分别为０／１７，１／１７。结论：蛋白印迹法检测血清中ＣＡＥ－Ａｂ比酶联免疫法更敏感，特异性高。但蛋白印迹法比酶联免疫法操作复杂，费用较高。

Objective: To improve positive rate of thymoma diagnosis. Methods: Antibodies to CAE (citric acid extract of human skeletal muscle) were evaluated by Western blotting and ELISA respectively in sera of myasthenia gravis patients (16 cases with and 17 cases without thymoma),normal adults(10 cases) and other disease patients (18 cases). Results: The rates of CAEAbs to 3.4104, 5.0104, 6.0104 ingredients of CAEantigen in MGT patients were 93.7% (15/16),75.0% (12/16), 75.0% (12/16) respectively. None of other groups was binding to each of these 3 ingredients. The positive rates of MGT patients were 16/16,12/16 respectively. The false positive rates were 0/17,1/17 respectively. Conclusion: Western blotting assay was more sensitive and specific than ELISA in evaluating CAEAbs.But the operation of Western blotting assay is more complicated and expensive than ELISA.