Highly pathogenic avian influenza (HPAI) H5N1 virus has the potential threat to poultry industry. Current avian influenza H5N1 vaccines for poultry are clade-specific, Therefore, there is an urgent need to develop an effective vaccine for preventing and controlling H5N1 viruses from different clades.
Recombinant L.lactis /pNZ8148-Spax-HA was generated which influenza virus hemagglutinin (HA) protein of A/chicken/Henan/12/2004 was displayed on the surface of Lactococcus lactis ( L.lactis ) and Spax was used an anchor protein. Chickens vaccinated orally with the unadjuvanted L.lactis /pNZ8148-Spax-HA could produce significant humoral and mucosal responses, as well as the neutralizing activities against different clades of H5N1 viruses. Importantly, the unadjuvanted L.lactis /pNZ8148-Spax-HA could conferred cross-clade protection against lethal challenge with different H5N1 viruses in the chicken model.
This study provides insight into the cross-clade protection conferred by the unadjuvanted L.lactis /pNZ8148-Spax-HA that may help establish a promising platform for the development of a safe and effective H5N1 cross-clade vaccine in poultry. Keywords: L.lactis /pNZ8148-Spax-HA, cross protection, H5N1 cross-clade vaccine.