融合表达小鼠IgG2b-Fc可增强人类免疫缺陷病毒1型Gag DNA疫苗的免疫原性

为阐明小鼠IgG2b-Fc对DNA疫苗免疫原性的增强作用,首先构建表达人类免疫缺陷病毒1型(human immunodeficiency virus type 1,HIV-1)CN54Gag基因的DNA疫苗及表达Gag与小鼠IgG2b-Fc融合基因的DNA疫苗,限制性酶切和DNA测序结果表明这两个疫苗均构建成功,蛋白免疫印迹结果也显示其正确表达。然后,利用上述DNA疫苗接种C57BL/6小鼠,比较两个DNA疫苗所诱导的特异性体液免疫反应和特异性细胞免疫反应。结果显示,融合表达小鼠IgG2b-Fc对特异性细胞免疫和体液免疫反应均有增强作用,但只有对特异性体液免疫反应的增强作用有统计学意义。

Fusion expression of mouse IgG2b-Fc improves immunogenicity of human immunodeficiency virus type 1 Gag DNA vaccine

To explore the immunogenicity of DNA vaccine expressing IgG2b‐Fc ,eukaryotic expression vectors pSV‐Gag and pSV‐Gag‐IgG2b were constructed .The constructed DNA vaccines were validated by restriction enzyme digestion and DNA sequencing .Western blotting results showed both of the two DNA vaccines could be expressed at appreciable levels in vitro .C57BL/6 mice were injected with these two DNA vaccines by intramuscular injection and their antigen‐specific humoral responses and T cell responses were compared after the last immunization .The results showed that human immunodeficiency virus type 1 (HIV‐1) Gag fused with mouse IgG2b‐Fc elicited superior Gag‐specific humoral responses and T cell responses ,but there was only significant increase in antigen‐specific humoral responses between the two DNA vaccines .