Fig. 3
EP4 inhibits FoxO1, enhances Stat3 phosphorylation, and is upregulated in a positive feedback loop. a RT-PCR and b flow cytometric analysis of FoxO1 in CD4+ T cells from patients with AS after 3 days of in vitro stimulation with PGE2 or an EP4 or EP2 agonist (n = 10 for RT-PCR, n = 6 for flow cytometric analysis¸ *p < 0.05, **p < 0.01; p value calculated using Friedman test). c RT-PCR analysis of STAT3 in CD4+ T cells from patients with AS after 3 days of in vitro stimulation with PGE2 or an EP4 or EP2 agonist (n = 10). d Flow cytometric analysis of STAT3 and e pSTAT3 expression in IL17+CD4+ T cells from patients with AS after 3 days of in vitro stimulation with PGE2 or an EP4 or EP2 agonist (n = 7, *p < 0.05; p value calculated using Friedman test). f EP4 upregulation in IL17+CD4+ T cells from patients with AS and from HC after 3 days of in vitro stimulation with PGE2 or an EP4 or EP2 agonist. Protein quantification of western blot analysis is shown and was performed using the LabImage software (n ≥ 3, *p < 0.05 calculated using Wilcoxon test). g Flow cytometry analysis of EP4 expression in IL17+CD4+ T cells from patients with AS. h Cell culture supernatants from CD4+ T cells from patients with AS were collected after 3 days of stimulation with PGE2 or an EP4 or EP2 agonist and analyzed by ELISA for the secretion of cytokines (n = 6, *p < 0.05, **p < 0.01, p value calculated using Friedman test). Data are shown as mean ± SEM