牛对表达口蹄疫病毒复合多表位基因的重组鸡痘病毒以及DNA疫苗联合免疫的免疫应答

Immune Responses in Cattle Primed and Boosted with Recombinant Fowlpox Virus and DNA Vaccine Expressing Chimeric Foot-and-Mouth Disease Virus Multiple Epitopes Gene

将构建的共表达口蹄疫病毒(foot-and-mouth disease virus,FMDV)复合多表位基因和猪白细胞介素18基因的重组鸡痘病毒活载体疫苗vUTA2-OAT以及DNA疫苗pVRI-OAT,分别以vUTA2-OAT/vVTA2-OAT(首免/加强免疫)、pVRI-OAT/vUTA2-OAT(首免/加强免疫)和vUTA2-OAT/pVRI-OAT(首免/加强免疫)等3种方式接种牛,然后通过间接ELISA、中和试验和T淋巴细胞增殖试验评价其诱导的特异性体液和细胞免疫水平。结果表明,这3种方式均能诱导牛产生特异性的体液免疫及细胞免疫应答,其中pVRI-OAT/vUTA2-OAT联合免疫方式的免疫效果最佳,诱导的中和抗体达1∶64,已接近于常规灭活疫苗免疫方式,而且其可以诱导比灭活疫苗免疫方式高得多的细胞免疫水平(P<0.01)。上述试验结果为进一步进行免疫攻毒试验,并最终筛选出最佳疫苗和免疫程序奠定了基础。

A recombinant fowlpox virus vUTA2-OAT and another rDNA vaccine plasmid pVRI-OAT both co-expressing chimeric foot-and-mouth disease virus multiple epitopes gene and porcine IL-18 gene were constructed and reported in our previous studies. In this study,cattle were inoculated using these 2 recombinant vaccines by 3 vaccination strategies of vUTA2-OAT/vUTA2-OAT, pVRI-OAT/vUTA2-OAT, vUTA2-OAT/pVRI-OAT, respectively. The results of C-ELISA, VNT and iymphoproliferation assay indicated all of these strategies could induce specific humoral and cellular immune responses against FMD. In particular, these results suggested that vaccination strategy of pVRI-OAT/vUTA2-OAT could induce the best immune response,comparing with conventional inactivated vaccine, which could induce not only approximately the same anti-FMDV antibody level （titre of neutralizing antibody was 1 ： 64）,but also the higher cellular immune responses.