Structure and function of collectin liver 1 (CL-L1) and collectin 11 (CL-11, CL-K1)

Immunobiology. 2012 Sep;217(9):851-63. doi: 10.1016/j.imbio.2011.12.008. Epub 2012 Feb 4.


The collectins are a group of innate immune proteins structurally characterized by their content of a carbohydrate recognition domain and a collagen-like region. Collectin liver 1 (CL-L1) and collectin 11 (CL-11, alias collectin kidney 1, CL-K1) are the more recently described members of this group. Their genomic organization and protein structure reveal many similarities. However, CL-11 is a serum protein, whereas CL-L1 appears to be restricted to the cytosol of cells such as hepatocytes. Specificity analyses of the CRDs reveal some differences in their preferences for saccharides: CL-11 binds most avidly to l-fucose and d-mannose, whereas CL-L1 shows preference for d-mannose, d-fucose, N-acetylglucosamine, and surprisingly also d-galactose. CL-11 binds to various microorganisms including Escherichia coli, Candida albicans and Influenza A virus. Polymorphisms in the CL-11 gene (COLEC11) leading to deficiencies have recently been identified as causative for 3MC syndrome. The 3MC syndrome is associated with a wide spectrum of developmental features including facial dysmorphism, cognitive impairment, hearing loss and vesicorenal anomalies. Similar polymorphic associations were reported for the mannan-binding lectin-associated serine protease 3 (MASP-3), and falls into line with the observation that CL-11 is found in circulating complexes with MASP-1/3. These findings suggest dual or overlapping functions of CL-11 in innate immunity and in fetal development.

Publication types

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

MeSH terms

  • Animals
  • Carbohydrates
  • Collectins / chemistry*
  • Collectins / genetics
  • Collectins / metabolism*
  • Complement System Proteins / metabolism
  • DNA / metabolism
  • Disease Models, Animal
  • Humans
  • Macromolecular Substances
  • Mannose-Binding Protein-Associated Serine Proteases / metabolism
  • Polysaccharides / metabolism
  • Protein Binding
  • Syndrome


  • Carbohydrates
  • Collectins
  • Macromolecular Substances
  • Polysaccharides
  • Complement System Proteins
  • DNA
  • Mannose-Binding Protein-Associated Serine Proteases