Lipoprotein-associated phospholipase A2 (Lp-LA2, which is also known as the platelet-activating factor acetyl hydrolase) is a Ca2+-independent phospholipase that circulates in the bloodstream in the form of a complex with lipoprotein particles.
Lp-PLA2 plays a crucial role in the metabolism of proinflammatory phospholipids and in the generation of proatherogenic metabolites, such as lysophosphatidylcholine and oxidized-free fatty acids. The majority of Lp-PLA2 is found in complexes with LDL, while the remaining portion is bound to HDL. The distribution of Lp-PLA2 over lipoprotein classes correlates with the pathophysiological state of individuals. The association of Lp-PLA2 with lipoproteins is dependent on its glycosylation pattern.