Immunogenicity of Recombinant Fowl-pox Vaccines coexpressing HA of AIV H5N1, H7N1 and chicken IL-18
Abstract: Three recombinant fowlpox viruses: rFPV-H5HA-IL18、rFPV-H5HA-H7HA-IL18 and rFPV-H5HA were administered to one-day-old specific pathogen free (SPF) chicken and seven-day-old commercial Leghorn egg laying chicken by wing web route. At 7, 14 and 21 days post infect, hemagglutination inhibition (HI) antibody titer and nonspecific cellular immunity level were quantified. The results showed all rFPV-vaccinated groups produced HI antibody, and cellular immunity levels induced by rFPV-H5HA-IL18 and rFPV-H5HA-H7HA-IL18 strains were significantly higher than that induced by rFPV-H5HA. At 21days post-inoculation, immunized SPF chicken and commercial Leghorn egg laying chicken were challenged with H5N1 HPAIV. rFPV-H5HA-IL18 and rFPV-H5HA-H7HA-IL18 strains could induce 10/10 protection against challenge with HPAIV. rFPV-H5HA strain induced 90% protection. For immunized egg laying chicken groups, cloacal swabbing samples were collected at 7 days post challenge, and no shedding was found in groups vaccinated with rFPV-H5HA-I