FIG. 3.

PAK and PAK ΔfliC inhibit IL-1β-activated NF-κB activation. NF-κB-luc-expressing Calu-3 cells were left untreated (control) or incubated for 4 h with 50 ng/ml IL-1β, 10⁸ CFU/ml PAK, and/or 10⁸ CFU/ml PAK ΔfliC and then processed for luciferase activity measurement. Average luciferase ratios with respect to the control (± standard deviations) were plotted. IL-1β caused 20-fold stimulation over the control value (untreated cells). PAK reduced NF-κB activation in the presence of IL-1β by 32%. PAK ΔfliC reduced NF-κB activation in the presence of IL-1β by 40%. The symbol # indicates significant difference from control cells. The symbol * indicates significant difference from IL-1β-treated cells. n = 3 for all data.