摘要
目的探讨猪繁殖与呼吸综合征病毒(PRRSV)自杀性DNA疫苗的免疫效果。方法将ORF5和ORF6基因分别插入可以同时表达两个外源基因的表达载体pSCA2的26S启动子下游,获得ORF5和ORF6双基因共表达自杀性DNA疫苗pSFV-56。结果Westernblot检测证实ORF5和ORF6基因获得正确表达,并且所表达的GP5和M蛋白可以形成异源二聚体。将pSFV-56免疫Balb/c小鼠,首免后4周可检测到特异性PRRSV中和抗体,首免后8周的中和抗体最高可达1﹕32,同时还可检测到较高的特异性细胞免疫应答。进一步将pSFV-56免疫断奶仔猪,二免后4周即可产生1:8～1:16的中和抗体,直到二免后6周仍维持这种高水平的中和抗体,而且也可检测到较高的特异性细胞免疫应答。结论上述研究结果表明pSFV-56具有良好的免疫原性和诱发免疫动物产生较高免疫应答的能力。
[Objective] To investigate the immune efficiency of the suicidal DNA vaccines of porcine reproductive and respiratory syndrome virus （PRRSV）. [Method] The ORF5 and ORF6 genes were subcloned into the downstream of two independent subgenomic promoter 26S of a suicidal DNA vaccine expression vector pCSA2 resulting in the plasmid pSFV-56 co-expressing GP5 and M proteins. [Result] The result of Western blot showed that the GP5 and M proteins were expressed and formed disulfided-linked heterodimer. The suicidal DNA vaccine pSFV-56 was injected Balb/c mice and piglets to evaluate the induced immunological responses in vivo. The specific detectable anti-PRRSV neutralizing antibodies were produced in the vaccinated mice at 4 weeks post primary vaccination （PPV） and reached a peak 1：32 at 8 weeks PPV. The specific stronger cell-immunity responses were also observed. In addition, it was observed that the 1：8-1：16 neutralizing antibodies of the vaccinated piglets and the specific cell-immunity responses were produced. [Conclusion] The results of the present study indicated that the suicidal DNA vaccine pSFV-56 has well immunity and the capability inducing higher immune responses in the animals.
出处
《中国农业科学》
CAS
CSCD
北大核心
2006年第5期1011-1017,共7页
Scientia Agricultura Sinica
基金
国家自然科学基金项目(30300257)
国家"973"基础研究项目(2005CB523200)
