Development Of Porcine Epidemic Diarrhea Vaccine With VSV As Carrier

Emerging porcine epidemic diarrhea viruses（PEDV）have resulted in big economic loss globally since 2010.Of note,vaccine developed with classic genotype 1（G1）isolate such as CV777,cannot provide complete protection against genotype 2（G2）viruses.To date,G2b is the genotype which epidemic prevalently in China and other countries,however,no vaccine against them has been available now.Considering fastidious isolation of emerging PEDV in cell culture and difficulties in retaining infectivity upon further in vitro passage,highly attenuated recombinant vesicular stomatitis virus(r VSV_MT)was used as the vector in the study to express spike protein（S）of PEDV,aiming at developing the subunit vaccine for controlling G2b viruses.It was demonstrated that with 19amino acids in its cytoplasmic domain deleted,S protein could be incorporated into VSV particles and led to the generation of recombinant VSV(VSV_MT-S_?19)at high efficiency.In vivo studies showed that VSV_MT-S_?19 could induce PEDV-specific immunities effectively in mice and pigs via intramuscular rather than intranasal route.Of note,administration of VSV_MT-S_?19 in sow could stimulate effective passive immunities in neonatal piglets,which were protected against lethal-dosed challenge by virulent homologous PEDV.As the result,recombinant VSV could be the promising platform for rapidly preparing subunit vaccine against the emerging epidemic PEDV.