(a) Intensity expression of selected genes involved in the IL-6 signaling cascade in CD4+ T cells subsets after 6h treatment with 20 ng/ml IL-6 or control (PBS). (b) Ptpn2 (n = 2), pY-STAT1 (n = 2) and pY-STAT3 (n = 3) positive cells in CD4+ TN and TEM cells after 30 min IL-6 stimulation (20ng/ml) determined by flow cytometry. (c) Intracellular cytokine staining for IL-21 and IL-17A in CD4+ TEM cells from Ptpn2fl/fl, Lck-Cre Ptpn2fl/fl and Ptpn22−/− mice (n = 3). *** P < 0.0001, ** P < 0.01 (One-way ANOVA (c). Data are shown as mean ± s.d).