Murine mast cells secrete a unique profile of cytokines and prostaglandins in response to distinct TLR2 ligands

Exp Dermatol. 2009 May;18(5):437-44. doi: 10.1111/j.1600-0625.2009.00878.x.

Abstract

Mast cells (MCs) are important effector cells in host defense against bacteria. In the course of a bacterial infection, MCs can be activated by various mechanisms, i.e. bacterial toxins, endogenously produced infection-associated peptides or via complement receptors, fimbrial adhesion molecules and toll-like receptors (TLRs). While some of these mechanisms are well established, the effects of TLR2 ligand-driven MC activation are far less understood. Here, we show that murine mature connective tissue-type MCs, but not immature bone marrow-derived cultured mast cells, express significant amounts of full length TLR2 on their surface. Activation by various TLR2 ligands only induces the selective release of cytokines in peritoneum-derived cultured mast cells (PCMCs) with preferential secretion of pro-inflammatory cytokines (IL-6 > IL-17 > IFN-gamma TNF > IL-1 > GM-CSF) upon stimulation with lipoteichoic acid (LTA). This response is much lower in PCMCs stimulated with the TLR2/6 agonist macrophage-activating lipopeptide-2 (MALP-2), which most prominently triggers the release of the immunomodulatory cytokine IL-10. Furthermore, only LTA but not MALP-2 induces prostaglandin D2 secretion which is again restricted to the mature MC phenotype. These findings suggest that TLR2 ligand-mediated activation of mature MCs, i.e. tissue-residing cells, which most likely occurs during infection, can selectively raise a potent inflammatory or anti-inflammatory response, depending on TLRs which are engaged.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Marrow Cells / cytology
  • Cell Separation
  • Cytokines / biosynthesis*
  • Flow Cytometry
  • Ligands
  • Lipopeptides / biosynthesis
  • Lipopolysaccharides / pharmacology
  • Mast Cells / cytology*
  • Mice
  • Mice, Inbred C57BL
  • Phenotype
  • Prostaglandin D2 / metabolism
  • Prostaglandins / biosynthesis*
  • Teichoic Acids / pharmacology
  • Toll-Like Receptor 2 / biosynthesis*

Substances

  • Cytokines
  • Ligands
  • Lipopeptides
  • Lipopolysaccharides
  • Prostaglandins
  • Teichoic Acids
  • Tlr2 protein, mouse
  • Toll-Like Receptor 2
  • lipoteichoic acid
  • macrophage stimulatory lipopeptide 2
  • Prostaglandin D2