Secretion of Microbicidal Alpha-Defensins by Intestinal Paneth Cells in Response to Bacteria

Nat Immunol. 2000 Aug;1(2):113-8. doi: 10.1038/77783.

Abstract

Paneth cells in mouse small intestinal crypts secrete granules rich in microbicidal peptides when exposed to bacteria or bacterial antigens. The dose-dependent secretion occurs within minutes and alpha-defensins, or cryptdins, account for 70% of the released bactericidal peptide activity. Gram-negative bacteria, Gram-positive bacteria, lipopolysaccharide, lipoteichoic acid, lipid A and muramyl dipeptide elicit cryptdin secretion. Live fungi and protozoa, however, do not stimulate degranulation. Thus intestinal Paneth cells contribute to innate immunity by sensing bacteria and bacterial antigens, and discharge microbicidal peptides at effective concentrations accordingly.

Publication types

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

MeSH terms

  • Animals
  • Escherichia coli / immunology
  • Intestine, Small / immunology
  • Intestine, Small / metabolism
  • Lipid A / immunology
  • Lipopolysaccharides / immunology
  • Matrix Metalloproteinase 7 / genetics
  • Matrix Metalloproteinase 7 / physiology*
  • Mice
  • Mice, Knockout
  • Paneth Cells / drug effects
  • Paneth Cells / immunology*
  • Paneth Cells / metabolism
  • Paneth Cells / microbiology
  • Protein Precursors / immunology*
  • Salmonella typhimurium / immunology
  • Staphylococcus aureus / immunology
  • Teichoic Acids / immunology

Substances

  • Lipid A
  • Lipopolysaccharides
  • Protein Precursors
  • Teichoic Acids
  • cryptdin
  • lipoteichoic acid
  • Matrix Metalloproteinase 7