猪伪狂犬病病毒的分离鉴定及免疫原性初步研究

Isolation and Identification of Porcine Pseudorabies Virus ZJ Strain and Research of its Immunogenicity

采集浙江某猪场疑似猪伪狂犬病发病仔猪的脑、脾脏等组织病料,经PCR检测为猪伪狂犬病病毒(pseudorabies virus,PRV)野毒感染,用BHK-21细胞进行病毒的分离培养,结果显示该病毒能引起典型的细胞病变,第4代病毒液毒价达107.0 TCID50/mL;PCR和动物回归试验结果表明该分离株为PRV,并将其命名为PRV ZJ株。将第4代病毒液制备成油乳剂灭活苗,免疫2kg左右家兔,免疫后28d采血并攻毒,测定其免疫原性,结果显示血清中和指数为13490,保护率为100%。本试验结果表明PRV ZJ株有很好的免疫原性,为进一步开展疫苗研究奠定基础。

The material from the clinical samples of cerebrum and spleen in the pigs characterized by pseudorabies, proved to be porcine pseudorabies virus （PRV） positive samples through the amplification of gE gene of PRV, was inoculated into the BHK-21 cells and serially passaged 4 times. The isolate could induce typical cytopathogenic effect in cells and the titer of the fourth passage was 10^7.0 TCID50/mL. Identification was done by PCR method and four rabbits were injected with the fourth generation cell cultures of the isolate, and the specific band could be amplified and the typical clinical syndrome could be observed. It was indicated that the isolated virus named ZJ strain was PRV. The virulent PRV ZJ strain was killed with formalin and used as vaccine antigen with oil adjuvant. The rabbits were injected with 1 mL vaccine, 28 days after inoculation, serum antibodies were detected and healthy rabbits were challenged by PRV ZJ virulent strain, and the protection rate and serum neutralization index of antibodies were tested. The results showed that protection rate and serum neutralization index in rabbits were 100 % and 13490, respectively. This study showed that PRV ZJ strain had good immunogenicity, and provided a basis for further research on vaccination of PRV.