STAT1 and infection: As shown in Fig. 5E, the level of pSTAT1 found in the SeV infected cells without IFN-α nAb pretreatment was apparently reduced in the cells with pretreatment at 3, 6 and 12 hrs post-infection, although the protein levels of STAT1 were not affected by the pretreatment, suggesting that pretreatment by IFN-α nAb suppressed the IFN signaling induced by virus infection.