Preparation of Glaesserella parasuis Ghosts Vaccine Delivering Porcine Circovirus Type 2 DNA Vaccine and Evaluation of Its Immunoprotective Effect in Mice
The aim of this study was to develop a combined vaccine against porcine circovirus type 2(PCV2)and Glaesserella parasuis(GPS),and to evaluate its immune protective effect in mice.We selected SH0165,a type 5 strain of GPS,as the vaccine strain.The G.parasuis ghosts were generated by chemically-induced lysis and the method is based on minimum inhibitory concentration(MIC)of sodium hydroxide(NaOH).Then,the ORF2 gene of PCV2 was cloned into the pEGFP-N1 vector.We developed a PCV2-GPS combined vaccine by using G.parasuis ghosts as vehicle for pEGFP-ORF2.Furthermore,four-week-old BALB/c mice were divided into commercial vaccine group,PCV2-GPS combined vaccine group,G.parasuis vaccine group,pEGFP-ORF2 group,PBS group,and blank group.The IgG antibody level against PCV2 and GPS,neutralization antibody against PCV2,PCV2 viral load of organs in mice,serum bactericidal activities,challenge protection efficacy,and level of cytokines(IFN-γ,IL-12)in serum were measured after immunization.The results showed that PCV2-GPS combined vaccine elicited significantly higher levels of IgG antibody response of PCV2 and GPS,neutralization antibody titer of PCV2,bactericidal activities and higher levels of IFN-γ than those of the control group.After PCV2 challenge,PCV2-GPS combined vaccine-immunized mice showed lower viral load in lymph nodes and lungs than the control group,and after challenge infection with GPS,immune protection efficacy of mice immunized was 70％(7/10).In conclusion,the PCV2-GPS combined vaccine significantly activated both humoral and cell-mediated immune responses,and inhibited the proliferation of PCV2 in mice,achieving a better protective effect in mice infected with GPS.The results provide biological materials and experimental data for the development of new,safe and efficient combined vaccines against porcine circovirus type 2 and Glaesserella parasuis.
porcine circovirus type 2ORF2 geneGlaesserella parasuisbacterial ghostmiceimmunoprotection
万方数据
维普
