Expression of IFN-inducible genes is independent of the NF-κB pathway and of extracellular factors. GEN2.2 cells were untreated or stimulated with Flu or CL097 in the absence or presence of the NF-κB inhibitors BAY and BMS. TRAIL (A) and CD40 (B) expressions were evaluated by flow cytometry after 4 hours and 24 hours of culture, respectively. The mean percentages and SDs from duplicate values of 4 independent experiments are shown. (C) GEN2.2 cells were untreated or stimulated for 2 hours. After washing, cells were placed in 24-well plates; untreated cells were added in transwells. After 4 hours of culture, TRAIL expression was evaluated by flow cytometry on cells in wells and transwells. Data shown are the means and SDs from duplicate values of 3 independent experiments. (D) GEN2.2 cells were untreated or stimulated for 2 hours in the absence or presence of anti–IFN-α/β and anti–IFN-α/βR neutralizing antibodies. After washing, cells were placed in 24-well plates; untreated cells were added in transwells. After 4 hours of culture, TRAIL expression was evaluated by flow cytometry on cells in wells and transwells. Data from 1 representative experiment are shown.