CRTH2 is a G-protein-coupled Chemoattractant Receptor-homologous molecule on Th2 cells (CRTH2). CRTH2 binds PGD2 http://bit.ly/VRpIq
The major prostanoid generated by mast cells is prostaglandin D2 (PGD2). Prostaglandin D2 (PGD2) binds to the receptor PTGDR, as well as CRTH2 http://bit.ly/Hayhv
Eicosanoid synthesis. Image source: Wikipedia.
Eicosanoids are signaling molecules made by oxygenation of 20-carbon essential fatty acids. There are 4 families of eicosanoids (PP-LT): prostaglandins (PG), prostacyclins (PGI), leukotrienes (LT) and thromboxanes (TX).
Prostaglandin D2. Image source: Wikipedia.
A CRTH2 receptor antagonist that blocks the effects of prostaglandin D2 (PGD2) is under development as asthma therapy http://bit.ly/MTIVb
DP1 antagonist laropiprant did not demonstrate efficacy in asthmatic patients or patients with allergic rhinitis. J Allergy Clin Immunol. 2009 Sep 11.