目的:用基因工程的方法克隆表达丙酮酸脱氢酶复合体E2(PDC-E2)融合蛋白,以用于人原发性胆汁性肝硬化(PBC)的早期发现和临床诊断.方法:针对PDC-E2的cDNA序列设计引物,从正常人的淋巴细胞中提取RNA,通过反转录PCR方法扩增得到相应的基因片段,经测定序列验证后插入表达载体pET28a(+),构建重组表达载体pET28a(+)-PDC-E2,转化大肠杆菌BL21(DE3)后诱导表达蛋白质.表达蛋白经SDS-PAGE、Western blot鉴定.结果:经核苷酸序列测定和酶切鉴定结果表明,成功地构建了PDC-E2重组质粒.IPTG诱导表达后,获得PDC-E2融合蛋白.经免疫学鉴定,重组抗原片段具有抗线粒体抗体二亚型(AMA-M2)的免疫原性.结论:获得PBC特异性靶抗原的多肽片段,为PBC的早期发现和临床诊断提供有力工具.
Objective:To express PDC-E2 recombinant fusion protein in E. coli. Methods:The cDNA encoding PDC-E2 was obtained by RT-PCR, confirmed by DNA sequencing, subcloned indirectionally into the bacterial expression plasmid pET28a( + ) and then transformed into E. coil. BL21 ( DE3 ) to express the recombinant fusion protein induced by IPTG. Results:The recombinant fusion protein exhibited the antigenicity of AMA-M2 by Western blot. Conclusion :The PDC-E2 recombinant fusion protein could be used for diagnosing PBC.