乙型脑炎重组痘苗病毒候选疫苗小鼠安全性评价

Evaluation of the safety of a recombinant vaccinia virus expressing the E gene of Japanese encephalitis virus(rVTT-JEVE) as a vaccine in mice

目的对重组痘苗病毒候选疫苗rVTT-JEVE进行动物安全性评价。方法用重组痘苗病毒rVTT-JEVE对BALB/c小鼠进行免疫接种,分别在体液免疫及细胞免疫水平上评价其免疫效果;并通过检测小鼠体内rVTT-JEVE病毒残留,分析乙型脑炎重组痘苗病毒候选疫苗rVTT-JEVE的安全性。结果 BALB/c小鼠经两次免疫接种后,重组痘苗病毒rVTT-JEVE组IgG抗体水平是商品疫苗SA-14-14-2组的1.4倍(t=3.704,P<0.05),中和抗体效价是SA-14-14-2组的1.6倍(t=4.418,P<0.05),T淋巴细胞增殖水平为SA-14-14-2组的1.7倍(t=3.092,P<0.05)。rVTT-JEVE接种小鼠后第1d各脏器均有rVTT-JEVE病毒残留,第3d颌下淋巴结已无病毒残留,第7d仅脾脏和雄性小鼠心脏有少量病毒残留,之后均无病毒残留。结论重组痘苗病毒候选疫苗rVTT-JEVE免疫小鼠可产生较好的免疫效果及免疫安全性。

Objective To evaluate the safety of a recombinant vaccinia virus,rVTT-JEVE,as a potential vaccine in animals.Methods BALB/c mice were immunized with the recombinant vaccinia virus rVTT-JEVE.The effectiveness of immunization was evaluated at the level of humoral and cell-mediated immunity.To further analyze the safety of the recombinant vaccinia virus rVTT-JEVE as a potential vaccine,viral residues of rVTT-JEVE in mice were studied.Results After BALB/c mice were immunized twice,the IgG antibody titer of mice immunized with the recombinant vaccinia virus rVTT-JEVE was 1.4 times that in mice immunized with a commercial SA-14-14-2 vaccine,so the titer in the former was significantly higher (t=3.704,P<0.05).The neutralizing antibody titer in mice immunized with rVTT-JEVE was 1.6 times that in mice immunized with SA-14-14-2,so the titer in the former was significantly higher (t=4.418,P<0. 05).The T-lymphocyte stimulation index in mice immunized with rVTT-JEVE was 1.7 times that in mice immunized with SA-14-14-2,so the stimulation index in the former was significantly higher (t=3.092,P<0.05).After mice were immunized,rVTT-JEVE remained in all organs on day 1,and no virus remained day 3 except in the submandibular lymph nodes.Moreover,only a small amount of virus remained in the spleen and the heart of male mice on day 7.No virus remained afterwards,indicating that it only remained in mice for 7 days.Conclusion The recombinant vaccinia virus rVTT-JEVE can provide more effective and safer immunization in mice.