重症肌无力患者血清连接素抗体的检测及其临床意义

Titin antibody in myasthenia gravis and its clinical significance

目的 探讨连接素 (titin或connectin)抗体 (titinab)与重症肌无力 (MG)的关系。方法 应用基因工程合成重组重症肌无力胸腺瘤特异性 30 0 0 0抗原 (MGT 30蛋白 ) ,并采用酶联免疫吸附法(ELISA)检测 141例不同胸腺病理类型的MG患者 (MG组 )、2 6 5名健康对照者 (NC组 )和 36例非MG其他疾病患者 (NMG组 )血清中titinab水平 ,同时检测MG患者血清中乙酰胆碱受体抗体 (AChRab)、突触前膜受体抗体 (PrsmRab)水平。结果 MG组血清中titinab水平明显高于NC组和NMG组 (均P <0 0 1) ;阳性率以MG伴胸腺瘤 (MGT)组最高 (83 7% ) ,MG伴胸腺萎缩 (MGA)组其次 (4 3 2 % ) ,而MG伴胸腺增生 (MGH)组及MG胸腺正常 (MGN)组患者血清中titinab均为阴性 ;NMG组中只有 1例 38岁女性患者 (多发性肌炎伴发甲状腺功能亢进 )titinab为阳性 ;MGH患者titinab水平与肌无力严重程度密切相关 (P <0 0 1) ;MGT患者titinab与AChRab、PrsmRab亦有明显相关性 (P <0 0 1)。结论 titinab检测可作为MGT术前诊断的重要参数 ,它在MGT、MGA病理过程中的作用机制有待进一步研究。

Objective To investigate the clinical significance of titin antibody(titinab) in myasthenia gravis(MG) Methods Recombinant MGT-30 peptide was synthesized by genetic engineering technique We had examined titinab in the sera of 141 MG patients with different thymic pathology(MG group),265 normal controls(NC group) and 36 diseased controls without MG(NMG group) using recombinant MGT-30 as antigen of ELISA Acetylcholine receptor antibody(AChRab) and presynaptic membrane receptor antibody(PrsmRab) were parallelly examined in MG patients Results The titer of titinab in the sera of MG patients was significantly higher than those of NC group and NMG group( P <0 01) and the positive rate of titinab was 83 7% in 49 MG patients with thymoma(MGT), 43 2% in 44 MG with thymic atrophy(MGA),however,all were negative in 38 MG with thymic hyperplasia(MGH) and 10 MG with normal thymic histology(MGN) In NMG group,only a 38-aged female patient with polymyositis and hyperthyroidism appeared positive There was a significant correlation between the titer of titinab and the severity of the muscular weakness in MGH patients( P <0 01),and the titer of titinab in sera of MGT patients was also significantly correlated to the serum level of AChRab and PrsmRab( P <0 01) Conclusion Recombinant MGT-30 peptide can be used as antigen to detect titinab in MG patients The determined level of titinab should be a helpful parameter in differential diagnosis of MGT prior to operation,and its function and role in the pathogenesis of MGT and MGA will be studied further