重组抗原检测抗干燥综合征A抗原的自身抗体

Recombinant antigen for detecting anti-SSA autoantibody

目的 建立便捷的检测抗干燥综合征 (SS)A抗原 (分子量为 6 0 0 0 0的多肽成分 )的自身抗体 (抗SSA)的方法 ,以利于疾病的早期诊断和病程监控。方法 构建基因工程菌 ,表达SSA 6 0 0 0 0融合蛋白。经GST柱层析法纯化后 ,分别经免疫印迹 (IBT)法和酶联免疫吸附法 (ELISA)检测 2 0份SS患者血清、6 0份系统性红斑狼疮 (SLE)患者血清和 30份正常人血清。结果 利用重组抗原检测抗SSA自身抗体敏感性较高 ,而且抗体滴度与SLE病程相关。用IBT法 ,SLE和SS患者的阳性率分别为43 3%和 10 % ;用ELISA法 ,SLE和SS患者的阳性率分别为 5 0 %和 2 5 %。结论 利用重组抗原对自身抗体进行定性、定量分析有助于对自身免疫病的诊断和监控。

Objective To detect the level of anti SSA 60 000 autoantibody in patients with autoimmune diseases as well as its assay methods.Methods We cloned Ro 60 000/SSA cDNA and expressed the SSA 60 000 GST fusion proteins in E.coli JM109. Purified recombinant antigens were used in immunoblotting test (IBT) and enzyme linked immunosorbent assays (ELISA) were developed. 20 SS sera, 60 SLE sera, 30 normal control sera were tested.Results The recombinant antigen improved the sensitivity for detecting anti SSA 60 000 autoantibody. Longitudinal studies of several patients with SLE showed that the titres of anti SSA 60 000 autoantibody were related to the course of disease.Conclusion Recombinant autoantigen is useful for analysis of auotantibody to diagnose and control diseases.