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

Abstract

To characterize neutralizing mimotopes, phages were selected from a 12-mer phage display library using three anti-porcine reproductive and respiratory syndrome virus (PRRSV) neutralizing monoclonal antibodies: (1) A1; (2) A2; and (3) A7. Of these, A2 and A7 recognize the mimotope, P2, which contains the SRHDHIH motif, which has conserved consensus sequences from amino acid positions 156 to 161 in the N-terminal ectodomain of GP3. The artificial multi-epitope gene, mp2, was designed by combining three repeats of the mimotope P2. The resulting sequence was inserted into the swinepox virus (SPV) genome to construct a recombinant swinepox virus (rSPV-mp2). The rSPV-mp2 was able to stably express the multi-epitope peptide, mP2, in vitro. The rSPV-mp2 immunized pigs exhibited a significantly shorter fever duration compared with the wtSPV treated group (P < 0.05). There was an enhanced humoral and cellular immune response, decreased number of PRRSV genomic copies, and a significant reduction in the gross lung pathology (P < 0.05) was observed following PRRSV infection in rSPV-mp2-immunized animals. The results suggest that the recombinant rSPV-mp2 provided pigs with significant protection against PRRSV infection.

Isolation and Characterization of Swinepox Virus from Outbreak in Russia

“…It can be used as a primary vaccine as SPV induces cellular and humoral immune responses in porcine models [38]. There are several examples of the successful use of the virus to immunize pigs against various porcine pathogens [34,[38][39][40][41]. SPV also exhibits a strong host specificity, only infecting pigs, although a wider host range has been reported in cultured cells [42].…”

Swinepox virus vector-based vaccines: attenuation and biosafety assessments following subcutaneous prick inoculation

“…With the advent of recombinant DNA techniques in the 1980s, Swinepox virus (SPV) was first considered as a recombinant vaccine vector almost 20 years ago [ 1 , 2 ]. Subsequently, recombinant SPV (rSPV) was tested as a vaccine delivery vector for various swine infectious diseases, most notably Streptococcus suis and swine influenza, because it is non-pathogenic and possesses the ability to carry and express large amounts of foreign genetic material [ 3 – 8 ].…”

“…Since the first demonstration in 1982 of the ability of vaccinia virus to express an inserted herpes simplex virus thymidine kinase (TK) gene [ 11 ], a large variety of foreign genes have been expressed by recombinant vaccinia viruses. To date, Streptococcus suis , porcine circovirus, swine influenza virus, swine infectious gastroenteritis virus and other pathogenic protective antigen genes have been successfully expressed in swinepox virus [ 3 – 8 ]. Swinepox virus has broad application potential as a live vector of the swine vaccine.…”

“…We have shown that rSPV is an excellent novel vaccine vector compared to traditional vaccines and that vaccine-vector combinations generate vastly different immune outcomes in a prime-boost setting. In particular, SPV has been considered a high biosafety standard live vaccine vector [ 3 – 6 , 8 ]. These studies have further confirmed that SPV can be optimized to become a veterinary live vector with high biosafety.…”