Effect of dexamethasone on inflammatory gene expression.

<p><b>A.</b> The effect of dexamethasone (1 µM) is shown on the induction of inflammatory genes by IL-1β (1 ng/ml) at 6 h. Data from Figures S2 and S3 were combined and the effect of dexamethasone expressed as a percentage of IL-1β for each gene. 100% indicates no effect of dexamethasone. Data (n = 9) are plotted as means ± SE. Genes are listed by descending efficacy to repression by dexamethasone. Statistical analysis was performed by non-parametric paired t-test. * <i>P</i><0.05; ** <i>P</i><0.01. <b>B.</b> Relationship between induction by IL-1β and repression by dexamethasone. The effect of dexamethasone (1 µM) expressed as a percentage of IL-1β is plotted against the fold induction of each gene. Data are derived from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053936#pone-0053936-g002" target="_blank">Figure 2A</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053936#pone.0053936.s002" target="_blank">Figure S2</a>. Linear regression was performed using GraphPad Prizm software. <b>C.</b> Repression by dexamethasone is shown for the most highly sensitive gene (IL-1β), two genes showing intermediate sensitivity (EFNA1 & IFIT3 isoform 2) and the lowest sensitivity gene (CFB) (that showed significant repression by 1 µM dexamethasone). Actual EC₅₀ values are indicated. <b>D.</b> Relationship between the effect of 1 µM dexamethasone (efficacy) and the sensitivity (log EC₅₀) of the repression by dexamethasone for individual genes. The effect of dexamethasone (1 µM) expressed as percentage of IL-1β is plotted against the log EC₅₀ for the repression of each gene. Data are derived from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053936#pone-0053936-g002" target="_blank">Figure 2A</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053936#pone.0053936.s003" target="_blank">Figure S3</a> respectively. Linear regression was performed using GraphPad Prizm software.