pT-ureB及pT-hpaA核酸疫苗诱导小鼠免疫应答的实验研究

Immune response to pT-ureB and pT-hpaA DNA vaccine in mice

目的观察并比较携带Hp不同抗原基因的质粒pTCAE-ureB(pT-ureB)和pTCAE-hpaA(pT-hpaA)肌注小鼠后诱导的体液免疫应答。方法构建真核表达质粒pT-ureB;与已成功构建的质粒pT-hpaA分别作为疫苗方案,肌肉注射免疫BALB/c小鼠并设置空质粒对照,末次免疫后第2、4、6周分别用间接ELISA法检测小鼠血清特异性IgG抗体滴度。结果两免疫组在末次免疫后第2周均可出现特异性IgG,抗体滴度随时间逐渐增高;末次免疫后第6周,两免疫组的抗体滴度与对照组相比较,差异极显著(P<0.01);且pT-ureB免疫组抗体滴度显著高于pT-hpaA(P<0.01)。结论pT-ureB具有良好的免疫原性,诱导体液免疫应答的能力优于pT-hpaA。

Objective To investigate and compare the humoral immune response induced by eukaryotic expression plasmid pTCAE-ureB （pT-ureB）and pTCAE-hpaA （pT-hpaA） injected intramuscularly in mice. Methods The ureB gene fragment was inserted into a eukaryotic expression vector pTCAE, and pTCAE-ureB was constructed. A total of 60 BALB/c mice were randomly assigned to be immunized by intramuscular injection of blank plasmid pTCAE, plasmid pT-ureB and pT-hpaA （n = 20 in each group）. Titers of specific IgG antibody in serum of each group were detected through ELISA respectively on week 2, 4, 6 after immunization. Results Specific IgG were observed in pT-ureB and pT-hpaA immunized groups and titers of antibody increased as time prolonged. IgG level was significantly higher in pT-ureB immunized group than in pT-hpaA group on week 6 after immunization. Conclusion Plasmid pT-ureB possesses good immunogenicity and induces a higher immune response than pT-hpaA.