Protective Efficacy And TEM Observation Of Recombinant Fowpox Virus Expressing HA Gene

Recombinant fowlpox virus(rFPV) have many strengths comparing with other ordinary vaccine,and many protective antigens of different viruses have been successfully expressed by using FPV since 1980s, and of course, included the recombinant fowlpox expressing influnenza gene and genes of the New Castle disease. In this paper, the expression of a single subtype of avian influenza H5 hemagglutinin (HA) gene of the recombinant fowlpox virus of recombinant fowlpox virus immunization were done to assess their protective efficacies,we also did some location research in the chicken embryo fibroblast cells.1. vaccination trials for evaluating protective efficacies of the rFPV-SYHA The SPF chickens were randomly divided into 5 groups, 6 feathers in each group.Four groups of SPF chickens were challenaged 1×105EID50 of H5 AIV strain SYat 21 days post- immunization by nasal inoculation with dose of 2×104, 2×103, 2×102, 20 and 2 PFU / plume. Compared with other groups, rFPV (2×104 PFU) and inactivated whole-virus vaccine significantly reduced the rate of detoxification of the trachea after four days of challenge. The immunization rates in the detoxification has no significant difference in other time. Infection with non-immune control group, rFPV (2×102 FPU) and higher-dose group were significantly reduced mortality, in which the morbidity and mortality of the rFPV (2×104 PFU) does not appear. rFPV (2×103 PFU) and the lower dose group have death rate in various degrees.2. localization of the HA protein in recombinant fowlpox virus of the CEFThe experiment results showed that the anti-H5 monoclonal antibody concentration is 1:200dilution by way of indirect enzyme immunohistochemistry on the cultured fibroblast cells of recombinant fowlpox virus. HA protein expression in cytosolic, membrane-based, nuclear-type could be seen, the most common are the former. Positive expression did not increase significantly with the time going on. It is predicted that be related closely with the promoter of the recombinant virus.We can apparently observe a large number of integral recombinant fowlpox virus after CEF infected with virus 48h by transmission electron microscope.