Phosphatidylserine recognition by phagocytes: a view to a kill

Trends Cell Biol. 2006 Apr;16(4):189-97. doi: 10.1016/j.tcb.2006.02.003. Epub 2006 Mar 10.

Abstract

The redistribution of phosphatidylserine (PS) to the external surface of the plasma membrane is a key element of apoptotic cell recognition and is a molecular cue that dying cells should be engulfed. Phagocytes interact with PS on apoptotic cells through either the PS receptor or secreted bridging proteins called opsonins. The study of two secreted PS opsonins, MFG-E8 and Gas6 and their receptors alphavbeta5 (and alphavbeta3) integrin and Mer tyrosine kinase, respectively, have provided insights into the temporal and spatial aspects of Rac1 activation following the recognition and internalization of apoptotic cells. Disruption of PS opsonins and their signaling pathways often manifest conditions of inflammation and autoimmune disease. Here, we review recent studies involving PS opsonins, their receptors and their role in the phagocytosis of apoptotic cells.

Publication types

  • Review

MeSH terms

  • Adaptor Proteins, Signal Transducing / immunology
  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Apoptosis
  • Integrins / metabolism
  • Mice
  • Models, Biological
  • Opsonin Proteins / metabolism*
  • Phagocytes / metabolism*
  • Phagocytosis
  • Phosphatidylserines / immunology*
  • Receptor Protein-Tyrosine Kinases / immunology
  • Receptor Protein-Tyrosine Kinases / metabolism
  • Receptors, Cell Surface / metabolism
  • Receptors, Immunologic / metabolism*
  • Signal Transduction*

Substances

  • Adaptor Proteins, Signal Transducing
  • Integrins
  • Opsonin Proteins
  • Phosphatidylserines
  • Receptors, Cell Surface
  • Receptors, Immunologic
  • opsonin receptor
  • Receptor Protein-Tyrosine Kinases