miR-146a expression is up-regulated by IL-2 or IL-15 but inhibited if IL-7 is also present. (A) Naïve T cells were cultured in the presence of IL-7, IL-2, IL-7 and IL-2, IL-15 or IL-7 and IL-15, all at 10 ng/ml. 28 days later 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 = 3 or 4. Statistical significance was analysed using GraphPad Prism software using one way ANOVA test (on paired data) with Tukey’s multiple comparison correction applied. Results with a p value <0.05 were considered to be statistically significant. *** = p <0.001. (B - D) Graphs showing % positive cells for CCR7+/CD45-RA+, CD28+ or CD62L + as assessed by FACS analysis. Each data point represents data from one donor, n = 3.