vUTAL3CP1重组载体疫苗与pVIRIL18P1 DNA疫苗在猪体内的免疫原性研究

目的 评价本课题组构建的共表达FMDV衣壳蛋白前体P1-2A基因以及免疫辅助基因的重组鸡痘病毒vUTAL3CP1和重组DNA疫苗pVIRIL18P1在猪体内诱导特异性体液免疫和细胞免疫的能力。方法将上述2种疫苗采用4种不同的组合方式单独或联合给猪进行肌肉注射，用ELISA方法和中和实验检测猪产生的抗体水平，T淋巴细胞增殖反应、CTL反应以及T淋巴细胞亚类。结果这2种基因工程疫苗均能诱导猪产生特异性的体液及细胞免疫应答。其中单独免疫组vUTAL3CP1/vUTAL3CP1的效果最好，其诱导的抗体水平已接近于常规灭活疫苗，而细胞免疫水平则比后者高得多。联合免疫组中vUTAL3CP1／pVIRIL18P1可以诱导比vUTAL3CP1，vUTAL3CP1更高的CTL杀伤活性，但体液免疫水平略低。结论证实了这2种基因工程疫苗在猪体内均有良好的免疫原性。同时初步筛选出vUTAL3CP1/vUTAL3CP1和pVIRIL18P1／vUTAL3CP1组等较佳的免疫策略，为下一步的攻毒保护试验奠定了基础。

Immunogenicity of recombinant fowl-pox virus and DNA vaccine co-expressing foot-and-mouth disease virus P1-2A gene and pig IL-18 gene in pigs

Objective To evaluate the immunogenicity of recombinant fowl-pox virus vUTAL3CP1 co-expressing P1-2A gene and 3C~(pro) gene of foot-and-mouth disease virus(FMDV) and DNA vaccine plasmid pVIRIL18P1 co-expressing P1-2A gene and pig IL-18 gene in pigs.Methods Pigs were inoculated intramuscularly with these 2 recombinant vaccines alone or in combination.The FMDV antibody were detected by ELISA and NT.T lymphoproliferation test,cytotoxic T lymphocyte response test,and T lymphocyte subpopulation were performed.Results Specific humoral and cellular immune responses could be induced in all recombinant vaccines inoculated groups.The vUTAL3CP1/vUTAL3CP1 group had higher immunogenicity in 2 single immunizing groups.Comparing with inactivated vaccine,vUTAL3CP1/vUTAL3CP1 could induce the same FMDV antibody level and higher cellular immune responses in pigs.pVIRIL18P1/vUTAL3CP1 could induce higher CTL responses but lower antibody responses compared with vUTAL3CP1/vUTAL3CP1.Conclusion Both these 2 recombinant vaccines have good immunogenicity in pigs.The results suggest that vUTAL3CP1/vUTAL3CP1 and pVIRIL18P1/vUTAL3CP1 may be the most optimal vaccination strategies,which provides a support for further virus challenge tests.