Crystal-induced neutrophil activation. II. Evidence for the activation of a phosphatidylcholine-specific phospholipase D

Arthritis Rheum. 1993 Jan;36(1):117-25. doi: 10.1002/art.1780360119.


Objective: To investigate the involvement of phospholipase D in the signaling pathways activated by 2 pathologically relevant inflammatory microcrystals, monosodium urate (MSU) and calcium pyrophosphate dihydrate (CPPD).

Methods: Human peripheral blood neutrophils were used throughout. Phospholipase D activity was monitored by measuring 3 separate indices: 1) the mass of phosphatidic acid, 2) the levels of alkyl-phosphatidic acid, and 3) the levels of formation, in the presence of ethanol, of phosphatidylethanol. The latter 2 parameters were measured in cells labeled with 1-0-3H-alkyl-2-acetyl-sn-glycero-3-phosphocholine. The cells were stimulated with microcrystals of triclinic morphology.

Results: Both MSU and CPPD crystals induced a time- and concentration-dependent accumulation of phosphatidic acid mass and elevation in levels of alkyl-phosphatidic acid and phosphatidylethanol in prelabeled cells. The activation of phospholipase D by the microcrystals was partially sensitive to colchicine and largely resistant to pertussis toxin. Inhibition of phosphatidic acid formation by wortmannin or ethanol reduced the microcrystal-stimulated production of superoxide anions.

Conclusion: These results indicate that microcrystals stimulate phospholipase D in human neutrophils and that at least some of the functional consequences of neutrophil-microcrystal interactions may be dependent on this biochemical pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Androstadienes / pharmacology
  • Calcium Pyrophosphate / pharmacology
  • Colchicine / pharmacology
  • Crystallization
  • Enzyme Activation
  • Ethanol / pharmacology
  • Glycerophospholipids*
  • Humans
  • Hydrolysis
  • Neutrophils / drug effects
  • Neutrophils / metabolism*
  • Pertussis Toxin
  • Phosphatidic Acids / metabolism
  • Phosphatidylcholines / metabolism
  • Phospholipase D / antagonists & inhibitors
  • Phospholipase D / metabolism*
  • Superoxides / metabolism
  • Uric Acid / pharmacology
  • Virulence Factors, Bordetella / pharmacology
  • Wortmannin


  • Androstadienes
  • Glycerophospholipids
  • Phosphatidic Acids
  • Phosphatidylcholines
  • Virulence Factors, Bordetella
  • phosphatidylethanol
  • Superoxides
  • Uric Acid
  • Ethanol
  • Pertussis Toxin
  • Phospholipase D
  • Colchicine
  • Calcium Pyrophosphate
  • Wortmannin