Inhibition of NF-κB prevents fusion of macrophages. Rat alveolar macrophages (5 × 10⁶ cells/well in 24-well dishes) were cultured for 3 days in the absence or presence of increasing concentrations of aspirin or curcumin. Note that 10 μM curcumin induced macrophages to detach from the plate (Bar represents 2 mm; ^*P < .01 and ^**P < .001 versus control; SD; n = 5).