中文摘要：

目的：构建结核分枝杆菌（MTB）Rv1759c结构域（Rv1759cD domain,Rv1759cD）与人IL-2（hIL-2）融合基因,并在大肠杆菌中表达获得重组的融合蛋白Rv1759cD-IL-2。方法：用PCR方法从MTB H37Rv基因组扩增Rv1759cD基因片段,测序后与hIL-2基因构建融合基因,并克隆到表达载体pProEX HTa。融合基因在大肠杆菌DH5α中诱导表达,经SDS-PAGE分析后,分别与His mAb、IL-2mAb和结核病人血清进行Western-blot鉴定,采用Ni-NTA亲和层析纯化蛋白。结果：获得的Rv1759cD基因经测序与GenBank公布的序列完全一致,与hIL-2基因连接后,构建的融合基因在大肠杆菌中有效表达。表达蛋白相对分子量为30KDAa,与预测值相符;Western-blot结果显示,在相对分子量30KDAa处分别与His mAb和鼠抗IL-2 mAb形成结合带,并与结核病人血清出现特异性结合。通过Ni-NTA亲和层析,可得到纯化的目的蛋白。结论：成功表达、纯化和鉴定了Rv1759cD-IL-2融合蛋白,并有可能作为新型结核病疫苗的靶抗原。

英文摘要：

Objective：To construct the fused gene of Rv1759c domain（Rv1759cD） gene of Mycobacterium tuberculosis H37Rv（MTB） and human IL-2（hIL-2）,and to express the Rv1759cD-IL-2 fusion protein in E.coil DH5α.Methods：The Rv1759cD gene was amplified by PCR from the genome of MTB H37Rv strain.The fused gene of Rv1759cD and hIL-2 was constructed,which was cloned into expression vector pPRO EX HTa.The Rv1759cD-hIL-2 fused gene was expressed in E.coli DH5α induced by IPTG.The recombi-nant protein was identified by SDS-PAGE analysis and by Western-blot with His mAb,IL-2 mAb and sera from TB patients respectively.The fused protein was purified by Ni-NTA purification system.Results：The PCR product was 435bp and the sequence was the same with those of Rv1759cD gene in GenBank.The fused protein with 30KDAa relative molecular mass was consistent with that had been report-ed,which reacted with the specific monoclonal antibody against His mAb and IL-2 mAb respectively at 30KDAa bandings.It also had an apparent affinity bandings with the sera of TB patients.Conclusion：The fused protein Rv1759cD-IL-2 was expressed and purified suc-cessfully,and it would be a target antigen of new tuberculosis vaccines.