人源M2抗原检测M2抗体诊断抗线粒体抗体阴性原发性胆汁性肝硬化

目的 分析抗线粒体抗体（AMA）阴性的原发性胆汁性肝硬化（PBC）患者与AMA阳性PBC患者在临床症状，实验室诊断指标等方面的差异；对比用克隆表达的人源M2抗原建立的酶联免疫吸附试验（ELISA）法测定M2抗体，与经典的间接免疫荧光法测定AMA的敏感性高低。方法 测定63例PBC患者外周血中的AMA与M2抗体。结果 AMA在63例PBC患者中的阳性率为81%。而M2抗体为100%；AMA阴性的PBC患者抗核抗体（ANA），抗平滑肌抗体（ASMA）的阳性率高于AMA阳性的PBC患者，但在临床症状和其他实验室诊断标准上差异并无显著性。结论 酶联免疫吸附试验（ELISA）法检测M2抗体的敏感性高于间接免疫荧光法测定AMA，PBC患者外周血中AMA的阳性与否和疾病并无明显关联。

Detection of M2 in diagnosis of antimitochondrial antibody-negative pat ients with primary biliary cirrhosis using recombinant autoantigens from human sources

Objective To compare the biochemical and clinical features of antimitochondrial antibody (AMA) positive and negative primary biliary cirrhosis (PBC),and to compare the sensitivity of both the detection of M2 antibody using enzyme linked immunosobent assay (ELISA) with antigen expressed from human sources,and the detection of AMA using conventional indrect immunofluorecence for diagnosing PBC.Methods AMA and M2 antibodies were tested in 63 patients with diagnosed PBC.Results Serum AMA positive rate in PBC patients was 81%(51/63) compared with 100%(63/63) of M2 positive rate.Antinuclear and anti smooth muscle antibodies(ANA and ASMA) were more frequently positive in the AMA negative patients (83% vs 35%,and 42% vs 4%, P <0 05);Between AMA positive and AMA negative patients there was no significant difference in other biochemical and clinical features.Conclusion The sensitivity of this ELISA was higher than that of indrect immunofluorecence.The serological features of AMA negative PBC are not associated significantly with the clinical spectrum or coures of disease.