Effect of LPS, TNF-α, and fMLP on IκB-α gene expression in human neutrophils. (A) Cells (5 × 10⁶/mL) were cultured at 37°C in the presence or absence of 1 μg/mL LPS, 5 ng/mL TNF-α, or 10 nmol/L fMLP for the indicated times (in minutes). Total RNA was then extracted and processed for Northern blot analysis using an IκB-α cDNA probe. This experiment is representative of three. (B) Ethidium bromide staining of the gel corresponding to the autoradiograms depicted in (A).