HCV/HBV复合抗原基因的克隆、表达及免疫应答研究

为探讨ＨＣＶ／ＨＢＶ 复合疫苗的可行性，将合成的丙型肝炎病毒（ＨＣＶ）复合多表位抗原基因ＰＣＸ与ＨＢｓＡｇ 基因连接成ＰＣＸＳ基因，与β－半乳糖苷酶（ＧＺ）基因融合后在大肠杆菌及减毒鼠伤寒沙门氏菌中获得表达．目的蛋白ＧＺ－ＰＣＸＳ可被抗－ＨＢｓ 及抗－ＨＣＶ 抗体所特异识别．ＧＺ－ＰＣＸＳ抗原皮下注射免疫ＩＣＲ小鼠后，诱发了较高水平的抗－ＧＺ－ＰＣＸＳＩｇＧ反应．构建的重组减毒鼠伤寒沙门氏菌ＳＬ３２６１（ｐＷＲ／ＰＣＸＳ）口服免疫小鼠后，诱发了高水平的ＣＤ８＋ Ｔ细胞增殖反应及抗ＧＺ－ＰＣＸＳＩｇＧ反应．所有免疫小鼠均未见明显的毒副作用．该研究揭示，ＨＣＶ／ＨＢＶ 复合抗原可诱发特异性体液免疫及细胞免疫应答，而活菌苗口服可能是理想的免疫途径，为ＨＣＶ／ＨＢＶ 双价疫苗研究提供了一定的理论及实验依据．

Cloning,Expression and Immune Responses of a Hybrid Antigen Corresponding to Hepatitis C Virus and Hepatitis B Virus

In order to explore the possibility of HCV/HBV bivalent vaccine,a synthetic multi epitopes antigen gene PCX of HCV was fused with HBsAg gene.The recombinant gene PCXS was cloned into a β galactosidase expression vector pWR450 1 to highly express a fusion protein GZ PCXS in E.coli JM105 and attenuated Salmonella typhimurium SL3261,whose products were specifically recognized by anti HBs and anti HCV antibodies.After GZ PCXS antigen and recombinant SL3261(pWR/PCXS) bacteria were used to immunize ICR mice,high level of anti GZ PCXS IgG was induced by GZ PCXS antigen.Oral live SL3261(pWR/PCXS) bacteria also elicited significant proliferation responses of CD8 + T cells.All the immunized mice were safe without obvious toxicity.The results showed that the possibility of the bivalent of HCV/HBV vaccines and oral live vaccine might be the best route for this purpose.