基因佐剂注射时相对HBV preS2S疫苗免疫作用的影响

目的：HBV preS2S基因疫苗接种不同时相应用佐剂peDNA3．1IL-2／Fc，观察其对诱导免疫反应效果的影响。方法：采用HBV preS2S DNA基因疫苗作为基础免疫，重组质粒peDNA3．1IL-2／Fc作为佐剂加强免疫，设计实验组与HBVpreS2S基因疫苗同时及在注射BALB／c小鼠后第3天加用佐剂，采用0、2、4周的方案接种，检测各次接种后抗体水平、免疫脾细胞的杀伤活性、增殖活性和细胞因子分泌水平。结果：HBV preS2S注射3天后应用佐剂的免疫小鼠，其抗体滴度、免疫脾细胞杀伤活性、增殖活性和Th1型细胞因子分泌水平均比同时免疫组、单独应用HBV preS2S组及空载体对照组明显增强。结论：预先接种疫苗后加用IL-2／Fc佐剂，能明显增强疫苗免疫效应。

Raised immune responses of HBV preS2S DNA vaccines by administrating genetic adjuvant at different time

Objective:To study the different effect of fused gene IL-2/Fc administrated at different time on immune responses induced by HBV preS_2S genetic vaccine.Methods:BALB/c mice were immunized with purified recombinant plasmids at 0, 2, 4 weeks. Two groups were designed. One group were injected with pcDNA3.1S_2S at first, then pcDNA3.1IL-2/Fc was administrated after three days. While the other group were injected two plasmids at the same time. We compared the immune responses through detecting the anti-HBs titers, CTL cytotoxicity level, proliferation of lymphocytes and cytokines levels secreted by cultural splenocytes.Results:The data demonstrated that the humoral and cellular immune responses induced by pcDNA3.1IL-2/Fc as adjuvant and administrated after HBV preS_2S DNA vaccine 3 days mice were dominant higher than other groups.Conclusion:Genetic adjuvant administrated after Ag priming can enhance its effect.