Activation of the human contact system on neutrophil extracellular traps

J Innate Immun. 2009;1(3):225-30. doi: 10.1159/000203700. Epub 2009 Feb 20.

Abstract

Pattern recognition is an integral part of the innate immune system. The human contact system has been shown to interact with the surface of many bacterial and fungal pathogens, and once activated leads to the generation of antimicrobial peptides and the proinflammatory mediator bradykinin. Here we show that apart from these surfaces also neutrophil extracellular traps (NETs) provide a surface that allows the binding and activation of the contact system. In addition, we present evidence that M1 protein, a streptococcal surface protein, in concert with human fibrinogen triggers polymorphonuclear neutrophils to form NETs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Bacterial / immunology
  • Antigens, Bacterial / metabolism
  • Bacterial Outer Membrane Proteins / immunology
  • Bacterial Outer Membrane Proteins / metabolism
  • Carrier Proteins / immunology
  • Carrier Proteins / metabolism
  • DNA / genetics
  • DNA / metabolism*
  • Extracellular Space / genetics
  • Extracellular Space / metabolism*
  • Fibrinogen / immunology
  • Fibrinogen / metabolism
  • Humans
  • Immunity, Innate
  • Immunoproteins / metabolism*
  • Kininogens / metabolism*
  • Neutrophil Activation / immunology
  • Neutrophils / immunology*
  • Neutrophils / metabolism
  • Neutrophils / ultrastructure*
  • Serine Proteases / metabolism*
  • Streptococcus pyogenes / immunology
  • Streptococcus pyogenes / pathogenicity

Substances

  • Antigens, Bacterial
  • Bacterial Outer Membrane Proteins
  • Carrier Proteins
  • Immunoproteins
  • Kininogens
  • streptococcal M protein
  • Fibrinogen
  • DNA
  • Serine Proteases