突变型乙肝病毒前C-C基因疫苗免疫BALB／C小鼠的研究

Immune effects of mutated Hepatitis B Virus precore-core DNA vaccines in mice

目的了解乙肝病毒前C-C基因疫苗（VEC）的突变型VE2、VE4免疫BALB／c小鼠后诱发特异性体液和细胞免疫的效果。方法分别用突变型和非突变型DNA疫苗免疫BALB／c小鼠，ELISA法检测小鼠抗HBc、抗HBeIgG，免疫第28天取小鼠脾细胞用酶免疫斑点（ELISpot）方法和CTL杀伤试验检测特异性细胞免疫功能。结果VE2、VFA组抗HBe水平高于VEC组，抗HBc水平差异无统计学意义。3种质粒均能引发特异性细胞免疫反应，VE4、VE2强于VEC；联用VM7免疫后能使VEC、VE2、VFA特异性细胞免疫反应增强。结论突变型前C-C基因疫苗在诱导BALB／c小鼠特异性体液和细胞免疫方面优于突变前。7干扰索基因可作为基因佐剂增强HBVDNA疫苗诱导的特异性细胞免疫反应。

Objective To observe the immune effect of DNA vaccines encoding mutated HBV pre-c/c gene（VE2,VFA） in mice. Methods Three kinds of plasmid VEC（DNA vaccines encoding HBV pre-c/c gene）, VE2 and VEA were injected into the thigh muscles of different group of BALB/c mice. Blood and splenocytes from mice were isolated at 4 weeks after immunization. We also have mouse groups immunized with three of these plasmid combined with IFN-γ gene plasmids. The anti-HBc and anti-HBe antibody in peripheral blood in mice were detected by enzyme linked immunosorbent assay（ELISA）, antigen-specific cell immune responses were detected by CTL test and enzyme linked immunospot assay（ELISpot）. Results We found that anti-HBe titers of VE2 and VE4 immunizing groups are higher than VEC group （P〈0.05 ） . We also observed that VE2 and VFA could induce stronger antigen-specific immune responses than VEC and when combined with IFN-γ plasmid,the antigen-specific immune responses are stronger than those without combination immunization in mice （P〈0.05）. Conclusions The DNA vaccine VE2 and VE4 could induces stronger antigen-specific immune responses than VEC, and when combined with IFN-γ plasmid, the antigen-specific immune responses are improved in mice.