表达猪圆环病毒II型ORF2基因的重组猪伪狂犬病病毒的免疫原性

Immune efficacy in mice by recombinant pseudorabies virus PGO expressing ORF2 gene of porcine circovirus type 2

摘要:

摘要:【目的】为研制预防猪圆环病毒II型(PCV2)感染的重组伪狂犬病病毒(PRV)活载体疫苗。【方法】将PCV2 ORF2基因插入到PRV通用载体pG中，利用脂质体LipofectamineTM 2000试剂盒将重组转移质粒pGO与猪PRV弱毒HB98株DNA共转染猪睾丸(ST)细胞，通过3轮蚀斑纯化重组病毒。将重组病毒、商品化PCV2灭活苗及DMEM培养液分别免疫6周龄雌性昆明小鼠，4周后加强免疫1次，首免后第8周用PCV2强毒NY株对小鼠进行攻毒。【结果】成功获得表达ORF2基因的重组病毒PGO，首免重组病毒后小 鼠体内抗PCV2的ELISA抗体水平很低，二免后小鼠PCV2特异的ELISA抗体水平明显升高，并且重组病毒组能够激发PCV2特异的淋巴细胞增殖效应。攻毒试验表明重组病毒组和PCV2灭活疫苗组均能有效抵抗PCV2强毒攻击。【结论】表明表达ORF2基因的重组病毒PGO具有良好免疫原性。

Abstract:

Abstract:［Objective］We developed a recombinant pseudorabies virus (PRV) vaccine against porcine circovirus type 2 (PCV2).［Methods］PCV2 ORF2 gene was inserted into vector pG to produce the recombinant PRV vector pGO; the genome of PRV attenuated vaccine and the transfer plasmid pGO were transfected by using LipofectamineTM 2000 Reagent into swine testis cells for homologous recombination to obtain the recombinant PRV． Six-week-old female Kunming mice were immunized two intramuscular immunizations 4 weeks apart，and then challenged with the virulent PCV2 NY strain at 8 weeks after the first immunization．［Results］A recombinant PRV expressing PCV2 ORF2 was successfully constructed，and named PGO． There was a low ELISA antibody level of PCV2-specific humoral immune response elicited by recombinant virus PGO for the first immunization but high significantly for the second immunization．PCV2 antigen-specific T-cell proliferative responses can be elicited by immunization with recombinant virus． Challenge experiments show that the recombinant virus and PCV2 inactivated vaccine could both protect the mice against PCV2 challenge，suggesting that the recombinant virus can be an excellent potential vaccine．［Conclusion］The results show the recombinant PRV expressing PCV2 ORF2 had good immunogenicity.