Evolution of the lectin-complement pathway and its role in innate immunity

Nat Rev Immunol. 2002 May;2(5):346-53. doi: 10.1038/nri800.


Discrimination between self and non-self by lectins (carbohydrate-binding proteins) is a strategy of innate immunity that is found in both vertebrates and invertebrates. In vertebrates, immune recognition mediated by ficolins (lectins that consist of a fibrinogen-like and a collagen-like domain), as well as by mannose-binding lectins, triggers the activation of the complement system, which results in the activation of novel serine proteases. The presence of a similar lectin-based complement system in ascidians, our closest invertebrate relatives, indicates that the complement system probably had a pivotal role in innate immunity before the evolution of an adaptive immune system in jawed vertebrates.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Biological Evolution*
  • Complement Activation*
  • Evolution, Molecular
  • Humans
  • Lectins / chemistry
  • Lectins / physiology*
  • Mannose-Binding Protein-Associated Serine Proteases
  • Models, Immunological
  • Serine Endopeptidases / genetics
  • Serine Endopeptidases / physiology
  • Signal Transduction
  • Urochordata / immunology


  • Lectins
  • Mannose-Binding Protein-Associated Serine Proteases
  • Serine Endopeptidases