Construction And Immunological Characterization Of Recombinant Fowlpox Viruses Coexpressing NDV F Gene And IBDV VP0 Gene

A transfering vector was constructed by inserted NDV F gene and IBDV VPO gene, under the control of two synthetic promoters ATI P7. 5X20 which were conjugated at opposite direction inserted within the thymidine kinase (TK) gene of FPV 282E4 strain. The resulting vector , pVPO-2ATI-P7. 5x20-F, was co-transfected CEF cells by DOTAP Liposomal with 0.1 MOI of Fowlpox viruses(FPV) 282E4 strain, the co-transfected cultures were passaged for three generations in' CEF cells in the presence of 5'-bromo-deoxyuridine (5'-BrdU), and TK- FPV were isolated by the way of picking out separate phages, then recombinant FPV were screened for the expression of foreign proteins by indirect immunofluorescene assay and Western blot assay. The cells lysates infected with 2 recombinant FPVs from 19 FPV phages reacted positively with antibodies specific to NDV or IBDV in an Western blot assay.Wing-web inoculation of commercial leghorn layers, commercial broilers and specific pathogen free (SPF) chickens with the recombinant Fowlpox virus vFV282 resulted in the development of nonspecific cellular immunity and the development of antibodies to NDV and IBDV and neutralizing antibodies to NDV. The innoculated commercial birds could be protected against a lethal intramuscular NDV E48F8 strain challenge. The recombinant Fowlpox virus induced protection SPF chickens against NDV E48F8 strain, IBDV BC6/85 F4 strain and FPV 102 strain. The results suggested that the recombinant Fowlpox virus vFV282 could be a candidate vaccine against virulent NDV, IBDV and FPV in the future.