Effect of IL-1β and dexamethasone on inflammatory gene expression. A.

<p>A549 cells were either not stimulated (NS) or treated with IL-1β (1 ng/ml), dexamethasone (dex) (1 µM) or a combination of the two for 1, 2, 6 and 18 h. Cells were then harvested for RNA and real-time PCR was carried out for the indicated genes and GAPDH. Data (n = 3), normalised to GAPDH are expressed as either log₂ fold over NS at 1 h (left panel) or as percentage of IL-1β (right hand panel) and plotted as means. Genes are grouped based on expression patterns: ‘Early-phase’ genes are those which have a peak of expression at 1 or 2 h (top two graphs); ‘Late-phase’ genes have a peak of expression at 6 h or later with less than 50% of that peak expression observed at 1 or 2 h (bottom two graphs); and ‘Intermediate’ genes are those that fall into neither of the above categories (middle two graphs). <b>B.</b> Effect of dexamethasone from right hand panel of A is plotted at each time point for all genes repressed by dexamethasone. Significance was tested using one-way ANOVA with a Bonferroni post-test and is indicated: *, <i>P</i><0.05; ***, <i>P</i><0.001.