IRF7 and infection: Activated NF-κB exerts a negative regulatory effect against IFNs and their signaling pathway [55], while instead, IRF-3 (constantly and ubiquitously expressed) and IRF-7 (sparsely expressed in the absence of infection) together induce the immediate production of type I IFNs (IFN-α (subtype 4) and IFN-β) and elicit an effective antiviral action.