a, Naive CD4+ cells were stimulated in the presence (NaCl) or absence (none) of additional 40 mM NaCl and were analysed by FACS for phosphorylated p38 (p-p38; n = 5). b, Naïve CD4 cells were differentiated into Th17 cells as indicated in the presence or absence of NaCl and SB202190 (p38i) and analysed by qRT-PCR as depicted in the bar graph (n=7) or by FACS (the left row shows cells differentiated in the absence of TGF-β1). c, Naïve CD4 cells were stimulated for 3h in the presence or absence of NaCl and SB202190 and analysed by qRT-PCR for NFAT5 (n=4). d, Cells were transduced with NFAT5 specific (shNFAT5) or control shRNA (control), stimulated like in b) and analysed by FACS. The bar graphs depict qRT-PCR analyses of NFAT5, IL-17A and SLC5A3 (n=5). CCR6 was analysed by FACS (black histogram: control, grey histogram: shNFAT5, one representative experiment of four is shown). e, Cells were stimulated like in c), but analysed by qRT-PCR for SGK1 (n=4). f, Cells were transduced with a shRNA specific for SGK1 (shSGK1) or a control shRNA (control) and activated like in b), and analysed by FACS. Expression of SGK1 and IL-17A was determined by qRT-PCR (n=5). CCR6 was analysed by FACS (black histogram: control, grey histogram: shSGK1, one representative experiment of four is shown). g, Cells were cultured like in b), but in the presence or absence of the SGK1 inhibitor GSK650394 (SGK1i) and analysed by FACS. The bar graph shows qRT-PCR for IL-17A under similar conditions (n=5). FACS and qRT-PCR (relative expression) data depicted in bar graphs were normalised to controls.