Phosphatidylserine receptor and apoptosis: consequences of a non-ingested meal

Apoptosis, a physiological process of controlled cell death, is essential during embryonic development and for the maintenance of tissue homeostasis. In recent years the view has emerged that dying cells can provide specific signals that enable recruitment and recognition by phagocytes. Exposure of phosphatidylserine, the best characterized of such signals, allows safe clearance of apoptotic waste without induction of inflammation. Here I re-examine some of the arguments that underpin the importance of these clearance mechanisms in light of recent observations from an animal model that lacks the receptor specific for phosphatidylserine.