Interferon gamma, also known as IFNG, is a member of the type ? interferon family. This protein is a soluble cytokine with antiviral, immunoregulatory and anti-tumor properties and is a potent activator of macrophages. Mutations in this gene are associated with aplastic anemia. Recombinant Feline IFNG protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.