Seong Y R, Choi S, Lim J S, Lee C H, Lee C K, Im D S
Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Yusong PO Box 115, Taejon 305-600, South Korea.
Vaccine. 2001 Apr 6;19(20-22):2955-64. doi: 10.1016/s0264-410x(00)00534-x.
The E1 and E2 proteins of hepatitis C virus (HCV) are believed to be the viral envelope glycoproteins that are major candidate antigens for HCV vaccine development. We reported previously that the replication-competent recombinant adenovirus encoding core-E1-E2 genes of HCV (Ad/HCV) produces serologically reactive E1 and E2 proteins forming a heterodimer in substantial amounts. Here, we examined immunogenicity of the E1E2 proteins copurified from HeLa cells infected with Ad/HCV virus in mice. Furthermore, we constructed a replication-defective recombinant adenovirus encoding the core-E1-E2 genes of HCV (Ad.CMV.HCV) and examined immunogenicity of the virus in mice. The mice immunized intraperitoneally with the copurified E1E2 proteins induced mainly antibodies to E2, but not to E1 by Western blot analysis. The sera of mice immunized with the E1E2 inhibited the binding of E2 protein to the major extracellular loop of human CD81. E2-specific cytotoxic T cells (CTLs), but not antibodies to the E1E2 antigens were induced in the mice intramuscularly immunized with Ad.CMV.HCV virus. When immunized with both Ad.CMV.HCV virus and the E1E2, mice elicited E2-specific CTLs and antibodies to the E1E2 antigens. The results suggest that immunization of Ad.CMV.HCV virus combined with E2 protein is an effective modality to induce humoral as well as cellular immune response to E2 antigen.
丙型肝炎病毒（HCV）的E1和E2蛋白被认为是病毒包膜糖蛋白，是HCV疫苗开发的主要候选抗原。我们之前报道过，编码HCV核心-E1-E2基因的具有复制能力的重组腺病毒（Ad/HCV）可产生大量形成异二聚体的具有血清学反应性的E1和E2蛋白。在此，我们检测了从感染Ad/HCV病毒的HeLa细胞中共同纯化得到的E1E2蛋白在小鼠体内的免疫原性。此外，我们构建了一种编码HCV核心-E1-E2基因的复制缺陷型重组腺病毒（Ad.CMV.HCV），并检测了该病毒在小鼠体内的免疫原性。通过蛋白质印迹分析，腹腔注射共同纯化的E1E2蛋白免疫的小鼠主要诱导产生了针对E2的抗体，而非针对E1的抗体。用E1E2免疫的小鼠血清抑制了E2蛋白与人CD81主要细胞外环的结合。肌肉注射Ad.CMV.HCV病毒免疫的小鼠诱导产生了E2特异性细胞毒性T细胞（CTL），而非针对E1E2抗原的抗体。当用Ad.CMV.HCV病毒和E1E2同时免疫时，小鼠产生了E2特异性CTL和针对E1E2抗原的抗体。结果表明，Ad.CMV.HCV病毒与E2蛋白联合免疫是诱导针对E2抗原的体液免疫和细胞免疫反应的有效方式。
