Antiviral activity of porcine interferon omega 7 against foot-and-mouth disease virus in vitro

Foot-and-mouth disease (FMD) is a disease of worldwide economic importance, and vaccines play an important role in preventing FMDV outbreaks. However, new control strategies are still needed since FMDV outbreaks still occur in some disease-free countries. Currently, interferon (IFN)-based strategies have been demonstrated to be an efficient biotherapeutic option against FMDV; however, interferon omega (IFN-omega) has not yet been assessed in this capacity. Thus, this study evaluated the antiviral activity of porcine IFN omega 7 (PoIFN-omega 7) against FMDV. After the PoIFN-omega 7 was expressed and purified, cell proliferation assays and quantitative real-time reverse transciption-polymerase chain reaction were used to evaluate the effective anti-cytopathic concentration of PoIFN-omega 7 and its effectiveness pre- and post-infection with FMDV in swine kidney cells (IBRS-2). Results showed the rHis-PoIFN-omega 7 fusion protein was considerably expressed using Escherichia coli BL21 (DE3) strain, and the recombinant protein exhibited significant in vitro protection against FMDV, including two strains belonging to type O and A FMDV, respectively. In addition, PoIFN-omega 7 upregulated the transcription of Mx1, ISG15, OAS1, and PKR genes. These findings indicated that IFN-omega has the potential for serving as a useful therapeutic agent to prevent FMDV or other viral outbreaks in pigs.