miR-146a expression is modulated by cytokine exposure in naïve cells but constitutive in memory cells. (A) The relative expression of miR-146a was assessed by RT-PCR in freshly purified uncultured ex vivo memory cells or memory cells that had been cultured for 28 days in the presence of 10 ng/ml IL-7. Each data point represents the average of triplicates from an individual donor, n = 2 or 3. (B) Naïve T cells were cultured in the presence of IL-2 or IL-7 for 14 days and then either maintained in the same cytokine or transferred into IL-7 or IL-15 for a further 7 days, all at 10 ng/ml. Cells were harvested and assessed for miR-146a expression levels by RT-PCR. Each data point represents the average of triplicates from an individual donor, n = 4. Statistical significance was analysed using GraphPad Prism software using one way ANOVA test with Bonferroni’s multiple comparison correction applied. Results with a p value <0.05 were considered to be statistically significant. ** = p <0.01, *** = p <0.001.