The differential regulation of IL-17A and FoxP3 by Tpl2 is TGF-β-dependent.

<p>Naïve T cells were cultured under Th17 polarizing conditions for 3 days +/− 5 μg/ml anti-IL-2 or with IL-6 and IL-23. (A) IL-17A levels were measured by intracellular staining and flow cytometry. Cells were gated on CD4⁺ cells. (B) IL-17A, IL-22, and IL-10 secretion was measured by ELISA. (C) <i>Il17a</i>, <i>Il22</i> and <i>Foxp3</i> expression was quantified by RT-PCR. (A-C) Pooled Th0 and Th17 results depicted in Figs. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119885#pone.0119885.g001" target="_blank">1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119885#pone.0119885.g002" target="_blank">2</a> are shown again for comparison. N≥3. (D) Representative flow plots of CD4⁺ cells gating on IL-17A and FoxP3 in Th0 and IL-6 + IL-23 + TGF-β (various concentrations) conditions. (E) Naïve T cells were cultured for 3 days with IL-6, IL-23, and varying concentrations of TGF-β. Proportions of IL-17A and FoxP3 positive cells were measured by intracellular staining and flow cytometry. Cells were gated on CD4⁺ cells. N = 3. Error bars represent means ± sem. *p<0.05, **p<0.005.