Phospholipase A2 receptor:: a regulator of biological functions of secretory phospholipase A2

The phospholipase A(2) receptor (PLA(2))R) is a type I transmembrane glycoprotein related to the C-type animal lectin family that includes the mannose receptor. PLA,)R regulates a variety of biological responses elicited by specific types of secretory PLA(2)s (sPLA(2)s). Group IB sPLA(2) (sPLA(2)-IB) acts as an endogenous PLA(2)R ligand to induce cell proliferation, cell migration, and lipid mediator production. Analysis of PLA(2)R-deficient mice has suggested a potential role of the sPLA(2)-IB/PLA(2)R pathway in the production of pro-inflammatory cytokines in endotoxic shock. PLA(2)R is also involved in the clearance of sPLA(2)s, including group X sPLA(2) (sPLA(2)-X) and a particular type of snake venom sPLA(2), and clearance suppresses their potent enzymatic activities. In the circulation, the soluble form of PLA(2)R is constitutively present as an endogenous inhibitor of sPLA(2)s. This review will focus on recent findings on the roles of PLA(2)R in regulating sPLA(2) functions and summarize what is known about the other binding proteins for mammalian and snake venom sPLA(2)S. (C) 2002 Elsevier Science Inc. All rights reserved.