Properdin: emerging roles of a pattern-recognition molecule

Annu Rev Immunol. 2010;28:131-55. doi: 10.1146/annurev-immunol-030409-101250.

Abstract

Complement is an innate immune system that is a first line of defense against pathogens and facilitates elimination of apoptotic and injured cells. During complement activation, the complement convertases are assembled on target surfaces and initiate their proteolytic activities, a process that marks targets for phagocytosis and/or lysis. The complement alternative activation pathway has been implicated in a number of autoimmune conditions including arthritis and age-related macular degeneration. Properdin, a plasma component that is also released by activated neutrophils, is critical in the stabilization of alternative pathway convertases. Recently, it has been shown that properdin is also a pattern-recognition molecule that binds to certain microbial surfaces, apoptotic cells, and necrotic cells. Once bound to a surface, properdin can direct convertase formation and target uptake. New studies are now focusing on a role for properdin in inflammatory and autoimmune diseases. This review examines the new properdin findings and their implications.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Autoimmune Diseases / immunology
  • Complement Activation
  • Complement System Proteins / immunology
  • Humans
  • Inflammation / immunology
  • Neutrophils / immunology
  • Properdin / chemistry
  • Properdin / immunology*

Substances

  • Properdin
  • Complement System Proteins