Research On The Recombinant Virus Live Vaccine Of Pseudorabies And Porcine Parvovirus

Porcine parvovirus (PPV) and pseudorabies virus (PRV) are two important etiological agents causing swine reproductive failures,which occurr in high prevalence and cause great morbidity in infected swine, leading to great economic losses to swine industry. The conventional vaccines have been used to prevent PPV and PRV infections. However, they possessed some disadvantages in view of safety and convenience. A bivalent genetic engineering vaccine against PPV and PRV should be developed to meet with the practical need.The genome of PRV is a linear DNA molecule of about 150kb,which includes many nonessential genes into which foreign genes can be stably inserted. This makes attenuated PRV become a promising candidate for the development of a live vaccine vector. To construct recombinant virus of PRV and PPV, a pair of primers of VP2 gene was designed according to PPV NADL-2 genomic sequence reported by Ana I Ranz. After amplification from RFDNA, the fragment which was 2.114kb long was cloned in the plasmid pPR128 which digested with StuI and SphI and transformed into strain DH5a of E.coli, yielding plasmid pPR-VP2.PRV Min-A DNA and recombinant plasmid pPR-VP₂ DNA were co-transfected into PK-15 cells with lipofectamine,and several recombinant virus strains were screened out with Low agarose and Neutral red. The recombinant virus can be further developed as a live vectored vaccine against pseudorabies and Porcine parvovirus influenza.