(A) Activation of NF-κB by IL-1β. OCIM2 cells (2 × 10⁶/mL) were incubated at 37°C with increasing concentrations of IL-1β for 1 hour. Nuclear extracts were then prepared and assayed for NF-κB as described above. (B) Inhibition of IL-1β–induced NF-κB activation by PAO. Cells were treated with PAO for 1 hour and then with IL-1β for 1 hour. Nuclear extracts were prepared and assayed for NF-κB activity as described in Materials and Methods.