Recombinant Encephalomyocarditis Viruses Elicit Neutralizing Antibodies against PRRSV and CSFV in Mice

Abstract

Encephalomyocarditis virus (EMCV) is capable of infecting a wide range of species and the infection can cause myocarditis and reproductive failure in pigs as well as febrile illness in human beings. In this study, we introduced the entire ORF5 of the porcine reproductive and respiratory syndrome virus (PRRSV) or the neutralization epitope regions in the E2 gene of the classical swine fever virus (CSFV), into the genome of a stably attenuated EMCV strain, T1100I. The resultant viable recombinant viruses, CvBJC3m/I-ΔGP5 and CvBJC3m/I-E2, respectively expressed partial PRRSV envelope protein GP5 or CSFV neutralization epitope A1A2 along with EMCV proteins. These heterologous proteins fused to the N-terminal of the nonstructural leader protein could be recognized by anti-GP5 or anti-E2 antibody. We also tested the immunogenicity of these fusion proteins by immunizing BALB/c mice with the recombinant viruses. The immunized animals elicited neutralizing antibodies against PRRSV and CSFV. Our results suggest that EMCV can be engineered as an expression vector and serve as a tool in the development of novel live vaccines in various animal species.

Construction and immunogenicity of a recombinant swinepox virus expressing a multi-epitope peptide for porcine reproductive and respiratory syndrome virus

“…The role of NA in protection against PRRSV infection was demonstrated in pigs by passive antibody transfer 10 . Several viral targets that play a role in the induction of NA have been reported, including GP3, GP4, GP5, and M proteins 11 12 13 14 .…”