猪繁殖与呼吸综合征和猪2型圆环病毒病二联核酸疫苗的构建及其免疫效力

试验以猪繁殖与呼吸综合征（PRRSV）的ORF5和猪圆环病毒2（PCV-2）的ORF2为目的基因，以pIRES-neo为表达载体，构建了PRRSV—PCV-2二联核酸疫苗，并对其免疫原性进行了初步的研究，为研制安全有效的疫苗防制猪繁殖与呼吸综合征和猪2型圆环病毒病提供基础。

Construction and Immunogenicity of Associated DNA Vaccine of PRRS and PCV-2 Disease

Objective] The aim of the study was to construct associated DNA vaccine of PRRS (Porcine reproductive and respiratory syndrome) and PCV-2 (Porcine circovirus type 2) disease and study its immunogenicity. Method] In this study, the ORF 5 gene of PRRSV isolated in Liaoning was cloned into pIRES-neo expression vector, and the neo gene of pIRES-neo expression vector was substituted by the ORF 2 gene of the PCV-2 Mongolia strain to construct the recombinant expression vector. The expression in BHK cells was detected through Western blot and IFA. Then the ELISA antibody level and the number of spleen T lymphocytes were detected after Balb/c mice were immunized with this DNA vaccine. Result] The recombinant plasmid pIRES-ORF2-ORF5 was constructed successfully and could express the target proteins in BHK cells, as indicated by Western blot and IFA. There was no significant difference in ELISA antibody between pIRES-ORF2-ORF5 immunized group and inactived vaccine immunized groups, while the number of spleen T lymphocytes induced by DNA vaccine was higher than that induced by inactived vaccine. Conclusion] The recombinant plasmid pIRES-ORF2-ORF5 should induce good humoral immune response and cellular immune response in mice, providing the conditions for better prevention and control of PRRS and PCV-2 disease.