Expression Of Porcine Epidemic Diarrhea Virus Neutralizing Epitopes By Listeria Monocytogenes

Porcine epidemic diarrhea virus(PEDV)is the pathogen of Porcine epidemic diarrhea(PED),PEDS has made huge money lost for pig farms since it broke out in China in 2010.At present,the inactivated vaccine of the classic strain CV777 and its attenuated vaccine are widely used by injecting Houhai acupoint,but the protection rate is not ideal,the possible reasons may be :(1)the amino acid(s)has mutated in the S protein of epidemic strain,(2)injected through Houhai acupoint,the vaccine cannot effectively stimulate mucosal immunity.The whole genome epidemic strain PEDV/ CHN/Shanghai/2016-4 was sequenced,pair Blast N result showed the amino acids in neutralizing epitopes COE or S1D of its S protein really mutated with comparison to CV777 counterparts.Listeria monocytogenes infects host by invading intestinal epithelial cells,stimulating strongly mucosal immunity.The expression of fused proteins COE-EGFP or S1D-EGFP in was ascertained under confocal Western-blot results showed that the antibody against S1D was produced in mice orally or intravenously administrated with Listeria monocytogenes expressing fused protein S1D-EGFP.An indirect ELISA for detecting swine serum IgG to S1D epitope was constructed.This method lay the foundation of vaccine evaluation.