Interferon alpha contains a mixture of several proteins, all with structural, serological, and functional properties typical for natural interferon alpha (IFN-α). The major subtypes identified are IFN-α1, IFN-α2, IFN-α8, IFN-α10, IFN-α14 and IFN-α21. Of these, IFN-α2 and IFN-α14 are glycosylated.