Composition and functional role of the mucus layers in the intestine

Cell Mol Life Sci. 2011 Nov;68(22):3635-41. doi: 10.1007/s00018-011-0822-3. Epub 2011 Sep 25.


In discussions on intestinal protection, the protective capacity of mucus has not been very much considered. The progress in the last years in understanding the molecular nature of mucins, the main building blocks of mucus, has, however, changed this. The intestinal enterocytes have their apical surfaces covered by transmembrane mucins and the whole intestinal surface is further covered by mucus, built around the gel-forming mucin MUC2. The mucus of the small intestine has only one layer, whereas the large intestine has a two-layered mucus where the inner, attached layer has a protective function for the intestine, as it is impermeable to the luminal bacteria.

Publication types

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

MeSH terms

  • Animals
  • Enterocytes / chemistry
  • Enterocytes / cytology
  • Enterocytes / metabolism
  • Humans
  • Immunity, Mucosal / immunology
  • Intestinal Mucosa / anatomy & histology*
  • Intestinal Mucosa / chemistry*
  • Intestinal Mucosa / metabolism*
  • Intestinal Mucosa / microbiology
  • Intestines / anatomy & histology
  • Intestines / microbiology
  • Intestines / physiology
  • Models, Molecular
  • Mucins / chemistry
  • Mucins / metabolism


  • Mucins