Optimized production and antiviral activity evaluation of recombinant chicken interferon-alpha using an improved Baculovirus expression system

Despite extensive vaccination efforts, certain pathogens continue to pose significant challenges to the poultry industry. Interferons (IFNs) are crucial for innate immune defense against various pathogens. Chicken interferonalpha (chIFN-alpha) reportedly has good inhibitory activity against various pathogens. However, its production is often limited by low yields. This study aimed to enhance the production of chIFN-alpha using an improved baculovirus expression system and evaluate its antiviral efficacy both in vivo and in vitro. A recombinant bacmid carrying two copies of the chIFN-alpha gene was successfully constructed. The chIFN-alpha protein was obtained using the modified baculovirus expression system, and exhibited anti-vesicular stomatitis virus (VSV) activity of up to 5.0 x 106 IU/ml. Moreover, the administration of chIFN-alpha to SPF chicken inhibited H9N2 subtype low pathogenicity avian influenza virus (LPAIV) proliferation and reduced the viral-shedding rate. In the present study, we successfully expressed and purified chIFN-alpha at high yields, as well as demonstrated its strong antiviral activity in vivo and in vitro. These findings present an alternative approach for the efficient production of chIFN-alpha for therapeutic applications.