肝病毒表面抗原“a”决定簇病毒样颗粒的构建和鉴定

Construction and characterization of hepatitis B surface antigen ＂a＂ epitope virus-like particles

目的 构建一个以乙肝核心抗原为骨架的病毒样颗粒,乙肝表面抗原＂a＂决定簇呈现在该病毒样颗粒的表面.方法 乙肝adr血清型的HBsAg蛋白＂a＂抗原决定簇（aa139～148,CSKPTDGNCT）插入到HBcAg的第78位天冬氨酸和第79位脯氨酸之间,密码子优化之后基因合成,酶切后连接到表达载体上,在大肠埃希菌中进行表达,纯化后对蛋白进行电镜观察、ELISA检测抗原性、免疫兔后检测免疫原性.结果 构建得到预期的原核表达质粒,并在大肠埃希菌中表达,纯化后电镜观察为病毒样颗粒,ELISA检测证实具有良好的抗原性和免疫原性.结论 成功获得预期的带乙肝表面抗原＂a＂决定簇的病毒样颗粒,为其应用奠定基础.

Objective To construct virus-like particles of hepatitis B core antigen, with HBsAg ＂a＂ epitope exposed on the surface. Methods Hepatitis B surface antigen ＂a＂ epitope were inserted into the Hepatitis B core antigen, between the 78th （Asp） and the 79th （Pro） amino acids. The gene was synthesized after the codon optimized, then it was ligated to the express vector after been enzyme digest. The virus-like particles were observed by electron microscope and detected by ELISA after been expressed and purified. Immune the rabbits by the VLPs, then detect the antibody. Result The virus-like particles were confirmed by electron microscope. Its antigenicity and immunogenicity were identified by ELISA. Conclusion The prokaryotic express plasmid with the fusion gene has been constructed successfully. The virus-like particles have been expressed, purified and identified, which lays the foundation for its application in the further.