Submitted to: United States Japan Natural Resources Animal and Avian Health Panel
Publication Type: Abstract Only
Publication Acceptance Date: September 26, 2000
Publication Date: N/A
Technical Abstract: Outbreaks of respiratory disease in swine have been particularly severe since 1998. Many of these outbreaks have been caused by a new swine influenza virus (SIV) strain, H3N2, and have resulted in acute respiratory disease in nursery and finishing pigs, and abortions in gilt and sows. To date, SIV strain H3N2 continues to negatively impact the swine industry in North America. Current research has shown that human adenovirus-5 (Ad-5) replicates in pigs equally as well as swine adenoviurses and recombinant Ad-5 vaccines can stimulate broad and long-lasting immunity. Here, we report the construction of recombinant Ad-5 vaccines encoding the HA or the NP gene. The influenza virus, A/Swine/Iowa/99 (H3N2), was propagated in embryonated chicken eggs. The HA and NP gene amplified by RT-PCR were cloned into Track-CMV (Tr) vector, and inserted into E1 region of human Ad-5. Subsequently, the recombinant adenoviral vector was transfected into o293 cell line. Three recombinant adenoviruses, HA-Ad-Tr contains HA gene, NP-Ad-Tr holds NP gene, and Ad-Tr carries only adenovirus and Tr without inserted gene, were generated. The levels of hemagglutinin and nucleoprotein expressed from HA-Ad-Tr or NP-Ad-Tr were examined by Western Blot. This result was further confirmed by immunoprecipitation. Immunocytochemical assay revealed that almost every infected cell with HA-Ad-Tr or NP-Ad-Tr produced SIV hemagglutinin or nucleoprotein compared to Ad-Tr. These results indicate that our experimental recombinant adenoviruses may be a valuable vaccine for preventing swine influenza disease in pigs.