Figure 5.

The recognition of apoptotic neutrophils by macrophages is largely dependent on the appearance on the cell surface of an anionic phospholipid, phosphatidylserine (PS), which is normally confined to the cytosolic leaflet of the plasma membrane. Asymmetric distribution of PS across the plasma membrane is mainly due to the activity of a specialized enzymatic mechanism, aminophospholipid translocase (APLT). S-nitrosylation of critical cysteine residues in APLT results in its inhibition, leading to PS externalization. This in turn triggers not only effective clearance of apoptotic cells but also causes suppression of inflammatory response. iNOS, inducible nitric oxide synthase; NO, nitric oxide.