(A) Effect of the V protein on IL-6 activation by LPS. 293 cells stably expressing TLR4 were transfected with plasmids encoding V, P, SH or GFP and plasmids p1186hIL-6-F-Luc, phTK-RL and a plasmid encoding CD14. The transfected cells were then treated with LPS for 16 hours and assayed for luciferase activities as described in the Materials and Methods. (B) Effect of the V protein on NF-κB activation by TNF-α. L929 cells were transfected with plasmids encoding V, P, SH or GFP and plasmids pNF-κB-TATA-F-Luc and phTK-RL. The transfected cells were then treated with TNF-α for 16 hours and assayed for luciferase activities. The relative luciferase activity indicates ratio of F-Luc to R-Luc. Error bars are standard deviation of mean (SEM).