PTGER2 and rheumatoid arthritis: (e) Th17 cells from patients with RA and healthy controls were stimulated with the EP4 agonist misoprostol, prostaglandin E2 (PGE2), or the EP2 agonist butaprost for 3 days, and EP2 expression was analyzed by flow cytometry (n = 16; *p < 0.05).