Characterization of agapornis fischeri interferon gamma and its activity against beak and feather disease virus

This study sought to clone and sequence the interferon-gamma (IFN-gamma) gene of the Fischer's lovebird parrot (Agapornis fischeri). Raw264.7 cells treated with the expressed IFN-gamma protein exhibited an upregulation in inducible nitric oxide synthase protein expression and nitric oxide (NO) production coupled with increases in phagocytosis and pinocytosis, as well as an induction of interferon-stimulated genes through the activation of the NF-kappa B factor, all of which are indicators of the innate immune responses of the activated macrophages. Similar to the IFN-gamma protein of other species, the NO production activity of the parrot IFN-gamma protein decreased by 80% after exposure at 60 ?& nbsp;for 4 min. Additionally, only half of the NO production activity of the parrot IFN-gamma protein remained upon exposure to HCl for 30 min. These findings suggested that the parrot IFN-gamma protein was heat-labile and sensitive to acidic conditions. Therefore, all of these effects contributed to the blockage of the uptake of BFDV virus-like particles (VLPs) by cells, the nuclear entry of the Cap protein of BFDV VLPs, and the clearance of the virus from BFDV-infected parrots by the IFN-gamma protein of Agapornis fischeri. This study is the first to describe the cloning of the IFN-gamma gene of Agapornis fischeri and characterize the anti-beak and feather disease virus activity of the IFN-gamma protein of Agapornis fischeri.