title: Activation of monocyte/macrophage functions related to acute atheroma complication by ligation of CD40: induction of collagenase, stromelysin, and tissue factor.
abstract: BACKGROUND
  Plaque disruption with thrombosis commonly causes the acute coronary syndromes. Macrophages, abundant at sites of plaque rupture, release proteinases that weaken plaques and express tissue factor (TF), which initiates thrombosis. The signals that induce expression of these macrophage functions, particularly TF, remain obscure. Recent studies have localized the receptor CD40 and its ligand in human atheroma. This study tested the hypothesis that ligation of CD40 can activate key mononuclear phagocyte functions related to clinical manifestations of atheroma.
  
  
  RESULTS
  Stimulation of human monocytes/macrophages through CD40 by either membranes from activated T cells or recombinant CD40L (rCD40L) induced expression of interstitial collagenase, stromelysin, and TF protein and activity. In contrast, the soluble cytokines interleukin-1 or tumor necrosis factor-alpha did not induce or weakly induced TF expression. Neutralization with anti-CD40L antibody markedly inhibited these actions of both T-cell membranes and rCD40L.
  
  
  CONCLUSIONS
  By inducing the expression of matrix-degrading proteinases and of TF procoagulant, CD40 signaling may contribute to the triggering of acute coronary events.
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass 02115, USA.
authors.forename: F
authors.initials: F
authors.lastname: Mach
authors.forename: U
authors.initials: U
authors.lastname: Schönbeck
authors.forename: J Y
authors.initials: JY
authors.lastname: Bonnefoy
authors.forename: J S
authors.initials: JS
authors.lastname: Pober
authors.forename: P
authors.initials: P
authors.lastname: Libby
mesh_terms: D001161:Arteriosclerosis / Q000473:pathology / Q000503:physiopathology*; D015153:Blotting, Western; D019013:CD40 Antigens / Q000502:physiology*; D017364:Collagenases / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D008024:Ligands; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000473:pathology / Q000502:physiology*; D019278:Matrix Metalloproteinase 3 / Q000494:pharmacology; D009000:Monocytes / Q000473:pathology / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects; D013925:Thromboplastin / Q000494:pharmacology
chemical_list: D019013:CD40 Antigens; D008024:Ligands; D013925:Thromboplastin; D017364:Collagenases; D019278:Matrix Metalloproteinase 3