Fig. 2

STAT3 activation after ex vivo stimulation of CD4 + T cells from polyJIA patients. A PBMCs were left unstimulated (gray) or stimulated ex vivo for 30 min with IL-6 (purple), then activated/phosphorylated (p)STAT3 measured using flow cytometry. Histograms depict representative results from one experiment showing pSTAT3 in CD3 + CD4 + T cells from a healthy pediatric control (PC) and both treatment-naïve (TN) and post-treatment (PT) samples from 3 polyJIA patients (Pt 1–3). Black numbers represent the MFI of pSTAT3 in unstimulated cells and the purple numbers the MFI after IL-6 stimulation. B Samples were treated as in (A). Data represent the %pSTAT3 + cells in a stimulated sample distinct from when unstimulated, generated using Overton subtraction. Cells from treatment-naïve patients demonstrate less ex vivo response to cytokine stimuli than those from healthy pediatric controls, although not achieving significance (Mann–Whitney U test). Black bars represent mean ± SEM. IL-6: PC 85 ± 1.9% v TN 76 ± 2.4%, IFNα: PC 77 ± 1.5% v TN 69 ± 3.9%, and IL-27: PC 66 ± 2.1% v TN 64 ± 3.8%. PBMCs, peripheral blood mononuclear cells; IL, interleukin; MFI, mean florescence intensity; IFN, interferon