Expression of bovine interferon gamma in recombinant baculovirus and determination of its antiviral activity

Abstract:

The full-length bovine interferon gamma(BoIFN-γ) cDNA，including the secretion signal peptide coding region was recloned into baculovirus honor vectors pFastBac^TM1 of Bac-To-Bac system. These recombinant plasmids，pFastBac^TM1-BoIFN-γ，were transformed into DH10Bac host bacteria to get recombinant shuttle plasmids，rBacmid-BoIFN-γ. Recombinant baculovirus，rBac-BoIFN-γ，was generated for expressing BoIFN-γ，by transfecting recombinant Bacmid-BoIFN-γ with CellfectinRReagen into sf9 insect cells. BoIFN-γ efficiently expressed by recombinant baculovirus in sf9 cells was testified by indirect immunofluorescence assay and indirect ELISA with monoclonal antibody against Bovine interferon-γ. Furthermore，VSV*GFP，recombinant Vesicular Stomatitis Virus expressing green fluorescence protein and MDBK were used to determine the anti-viral activity of rBoIFN-γ. The result shows rBoIFN-γ could inhibit the replication of the VSV*GFP in MDBK cells and the antiviral activity of supernatant was 2×10⁵IU/mL. The antiviral activity of rBoIFN-γ could be blocked by anti-BoIFN-γ mouse serum. The results demonstrated that the recombinant baculovirus could express BoIFN-γ efficiently and rBoIFN-γ had high antiviral activity.

Key words:Interferon gamma; bovine; recombinant baculovirus; antiviral activity