多表位HBV重组DNA疫苗的构建与免疫效果评价

Construction of a recombinant HBV DNA vaccine and its evaluation for specific cellular immune response in mice

目的探讨多表位乙型肝炎DNA疫苗诱导特异性细胞免疫应答及其治疗慢性乙型肝炎的潜能。方法筛选一组HBV的表位,并进行优化组合,辅以一定的旁侧序列,并合成目的基因片段HS。将它插入可人用的真核表达载体pVAX1中,构建出重组质粒PVAX-HS。通过重组质粒免疫小鼠,观察免疫动物体内CTL。结果酶切结果显示成功构建了PVAX-HSDNA疫苗,ELISPOT测定证实其可以在小鼠体内诱导产生特异性T细胞,51Cr释放实验证实,所诱导的T细胞中具有很强的CTL活性。结论PVAX-HSDNA疫苗免疫可诱导特异性细胞免疫应答,具有慢性病毒性乙型肝炎治疗性疫苗的潜能。

Objective To study the specific cellular immune response induced by a recombinant HBV DNA vaccine and evaluate the potential therapeutic effect of this vaccine against HBV. Methods A series of HBV epitopes were screened and the optimal combinations of these gene fragments identified to construct the target gene HS which incorporated appropriate flanking sequences. HS was inserted in pVAX 1 to construct the recombinant plasmid PVAX-HS. Generation of specific cytotoxic T lymphocytes （CTLs） induced by PVAX-HS in HLA-A2 mice was observed by ^51Cr assay and the activity of the CTLs evaluated using ELISPOT assay. Results PVAX-HS was constructed successfully, which induced specific CTLs with strong activities after immunization in mice as compared with the control group that yielded negative results. Conclusion PVAX-HS DNA immunization can induced specific cellular immune response in mice, suggesting the potential therapeutic effect of this HBV vaccine.