IFNA2 and hepatitis C virus infection: In a hepatitis C replication assay, the EC50 values exhibited a narrow range of 2- to 6-fold differences among the IFNs (IFNα7: 36 fM, IFNω: 37 fM, IFNα2(YNS, H57Y, E58N, and Q61S): 20 fM, wild-type IFNα2: 116 fM).