Lysophospholipid metabolism facilitates Toll-like receptor 4 membrane translocation to regulate the inflammatory response

J Leukoc Biol. 2008 Jul;84(1):86-92. doi: 10.1189/jlb.0907601. Epub 2008 Apr 10.


Sepsis, an overwhelming inflammatory response to infection, is a major cause of morbidity and mortality worldwide and has no specific therapy. Phospholipid metabolites, such as lysophospholipids, have been shown to regulate inflammatory responses in sepsis, although their mechanism of action is not well understood. The phospholipid-metabolizing enzymes, lysophospholipid acyltransferases, control membrane phospholipid composition, function, and the inflammatory responses of innate immune cells. Here, we show that lysophosphatidylcholine acyltransferase (LPCAT) regulates inflammatory responses to LPS and other microbial stimuli. Specific inhibition of LPCAT down-regulated inflammatory cytokine production in monocytes and epithelial cells by preventing translocation of TLR4 into membrane lipid raft domains. Our observations demonstrate a new regulatory mechanism that facilitates the innate immune responses to microbial molecular patterns and provide a basis for the anti-inflammatory activity observed in many phospholipid metabolites. This provides the possibility of the development of new classes of anti-inflammatory and antisepsis agents.

MeSH terms

  • 1-Acylglycerophosphocholine O-Acyltransferase / antagonists & inhibitors
  • 1-Acylglycerophosphocholine O-Acyltransferase / metabolism
  • Cell Line
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism*
  • Down-Regulation / drug effects
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Inflammation / metabolism*
  • Lipopolysaccharides / metabolism
  • Lysophospholipids / metabolism*
  • Membrane Microdomains / drug effects
  • Membrane Microdomains / metabolism
  • Nystatin / pharmacology
  • Protein Transport / drug effects
  • Pyridines / pharmacology
  • Toll-Like Receptor 2 / metabolism
  • Toll-Like Receptor 4 / metabolism*
  • Tumor Necrosis Factor-alpha / biosynthesis


  • Enzyme Inhibitors
  • Lipopolysaccharides
  • Lysophospholipids
  • Pyridines
  • TLR4 protein, human
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • Tumor Necrosis Factor-alpha
  • Nystatin
  • 1-Acylglycerophosphocholine O-Acyltransferase