LPA5 Is Abundantly Expressed by Human Mast Cells and Important for Lysophosphatidic Acid Induced MIP-1 beta Release

Background Lysophosphatidic acid (LPA) is a bioactive lipid inducing proliferation, differentiation as well as cytokine release by mast cells through G-protein coupled receptors. Recently GPR92/LPA5 was identified as an LPA receptor highly expressed by cells of the immune system, which prompted us to investigate its presence and influence on mast cells. Principal Findings Transcript analysis using quantitative real-time PCR revealed that LPA5 is the most prevalent LPA-receptor in human mast cells. Reduction of LPA5 levels using shRNA reduced calcium flux and abolished MIP-1β release in response to LPA. Conclusions LPA5 is a bona fide LPA receptor on human mast cells responsible for the majority of LPA induced MIP-1β release