欧洲型PRRSV、PCV2二联重组痘苗病毒疫苗猪体免疫实验研究

目的评价实验室构建的欧洲型PRRSV和PCV2二联重组痘苗病毒猪体免疫效果。方法分别用重组痘苗病毒rVTT-PCV2-ORF2-EU-ORF3-ORF5和rVTT-EU-ORF3-ORF5进行猪体免疫试验,每周采血,分离血清,采用ELISA检测病毒特异性抗体、中和抗体检测及细胞因子水平,评价免疫效果。结果 rVTT-PCV2-ORF2-EU-ORF3-ORF免疫组35d时,猪血清欧洲型PRRSV GP3和GP5及PCV2ORF2特异性抗体,显著高于野毒组（t=6.61,t=9.21,t=10.34,P〈0.05）;猪血清中和抗体35d时,各免疫组均可产生较高的免疫水平,差异均无统计学意义（t=0.48,P〉0.05）;重组痘苗病毒疫苗rVV-ORF2-EU-ORF3-ORF5免疫可诱导IL-4和IFN-γ产生,增强猪体细胞免疫应答水平。结论欧洲型PRRSV、PCV2二联重组痘苗病毒疫苗能诱导猪体产生体液和细胞免疫应答,为欧洲型PRRSV、PCV2的新型疫苗研究奠定了实验基础。

Immunogenicity of a bivalent recombinant vaccine against European-type PRRSV and PCV2 in pigs

Objective To assess the immunological properties of a bivalent recombinant vaccine against European-type PRRSV and PCV2 in pigs. Methods Pigs were immunized with the recombinant vaccines rVTT-PCV2-ORF2-EUORF3-ORF5 and rVTT-EU-ORF3-ORF5.Blood was collected weekly and serum was separated to detect the level of virus-specific neutralizing antibodies and serum cytokines. Results On day 35,pigs immunized with rVTT-PCV2-ORF2-EU-ORF3-ORF5 had a higher level of antibodies specific to European-type PRRSV GP3 and GP5and PCV2ORF2 than pigs infected with wild-type viruses.Differences in levels of specific antibodies produced were statistically significant（t=6.61,t=9.21,t=10.34,P〈0.05）.Detection of serum neutralizing antibodies indicated that immunized pigs had higher levels of antibodies on day 35.Differences in antibody levels were not statistically significant（t=0.48,P〉0.05）.The recombinant vaccine rVV-ORF2-EU-ORF3-ORF5 induced IL-4and IFN-γ,enhancing the cellular immunity of pigs.Conclusion A bivalent recombinant vaccine against European-type PRRSV and PCV2 induced a better humoral response and cellular immune response,providing a new experimental basis for study of vaccines against European-type PRRSV and PCV2.