Phospholipase A2 activator protein (PLAP), activates PLA2 (phospholipase A2 enzyme) and is an important mediator of eicosanoid generation. Also known as a pro-inflammatory agent, PLAP has been found in inflamed tissues and synovial fluid from patients with rheumatoid arthritis. As such, it is believed to play an important role in the regulation of inflammatory diseases. The formation of PLAP can be stimulated by IL-1 beta and TNF-alpha.