Interferons (IFN) are a family of cytokines with potent antiviral, antiproliferative and immunomodulatory properties, classified based on their binding specificity to cell surface receptors . Human IFNA2 was originally cloned in the early ‘80s and now more than a dozen closely related IFN alpha subtypes have been identified in both the human and mouse genome, each sharing about 80% amino acid (aa) sequence homology. Structurally, type I IFNs belong to the class of five helical_x001E_bundle cytokines, with the IFNA subtypes containing 2 conserved disulfide bonds. The extracellular domain (ECD) of mature human IFNA1, also known as IFNA13, shares 63% aa sequence identity with mouse IFNA1. Two variants of human IFNA1 are known to exist, IFNA1a and IFNA1b, which only differ by a single residue at position 137. The type I IFNs bind to the interferon alpha receptor (IFNAR), which consists of two subunits: IFNAR1 (alpha subunit) and IFNAR2 (beta subunit).