TNF and viral infectious disease: To confirm the role of ICP22 in the inhibition of NF-κB activation in the context of virus infection, HeLa cells or primary human cervical fibroblasts were transfected with the reporter plasmids pNF-κB-Luc and phRL-TK for 4 h, followed by infection with HSV-2 or us1 del HSV-2, which was constructed as described previously (22), for 20 h, and a stimulation with TNF-α for another 6 h.