PLA1A is a phospholipase that hydrolyzes fatty acids at the sn-1 position of phosphatidylserine and 1-acyl-2-lysophosphatidylserine. This secreted protein hydrolyzes phosphatidylserine (PS) in liposomes and can also hydrolyze PS in apoptotic cells and activate platelets where the resulting 2-acyl-lysophosphatidylserine acts as a lipid mediator for mast cells, T cells, and neural cells, suggesting that a major function of PLA1A may be the production of lysophospholipid mediators. PLA1A is upregulated in rat peripheral blood cells bearing long-term surviving cardiac allograft. PLA1A is also expressed in human THP-1-derived macrophages and this expression is upregulated in cells treated with lipopolysaccharide, a TLR4 ligand. This upregulation is inhibited with corticosteroids, which are often used at high dosages to suppress chronic allograft rejection.
Phosphatidylserine-specific phospholipase A1; phosphatidylserine-specific phospholipase A1alpha; Phospholipase A1 member A; PS-PLA1