The prostanoid group including prostaglandin (PG) E2, PGD2, PGI2, PGF2 and thromboxane (TX) A2 are one of the lipid mediators which may play a role in the pathogenesis of atopic dermatitis (AD). PGE2, PGD2 and TXA2 are thought to be induced in dermal and regional lymph nodes on foreign antigen exposure. Also, the specific G protein coupled receptors EP2, 3, 4, DP are expressed on cutaneous dendritic cells suggesting that prostanoids play some role in antigen exposure to the skin. Maturation and migration of cutaneous dendritic cells are increased by EP4 but suppressed by EP3 and the DP receptor. These data imply that prostanoids have multiple roles in dermal immune responses ...