IRF-7, together with IRF-3, is known to play a pivotal role in the induction of IFN-α and IFN-β genes through binding with PRDI in cells infected with virus [3], [4], although it was suggested that IRF-7, rather than IRF-3, is important to suppress the infection and replication of HCV in the cells [10]. Here, IRF3 is linked to infection.