title: Leukocyte-platelet aggregates in acute and subacute ischemic stroke.
abstract: BACKGROUND
  Leukocyte-platelet aggregates appear to be a stable and sensitive marker of platelet activation as suggested by studies in coronary heart disease. We tested the hypothesis that leukocyte-platelet aggregates are increased after ischemic stroke and investigated the contribution of different leukocyte subtypes to such increase.
  
  
  METHODS
  We serially determined granulocyte-, lymphocyte- and monocyte-platelet aggregates, using flow cytometry at days 1, 2, 3, 5, 7, 10, and 90 in patients with ischemic stroke (n = 45) and in age- and sex-matched healthy control subjects (n = 30).
  
  
  RESULTS
  Granulocyte-platelet aggregates (granulocytes with > or =1 platelet/microl) were more common in patients than control subjects from day 1 through day 10 (p < 0.04, respectively), but not on day 90 after stroke. The percentage of granulocytes forming aggregates was increased on days 1-3 after stroke but not at other time points. Lymphocyte-platelet aggregates were not more common at any time point after stroke. Total numbers and percentages of monocytes forming platelet aggregates were significantly increased on day 2 (p = 0.003), but not at other time points after stroke.
  
  
  CONCLUSIONS
  The 3 leukocyte subtypes showed different kinetics regarding aggregate formation with platelets after ischemic stroke. Increase of monocyte-platelet aggregates is short-lived and may reflect an acute reaction to cerebral ischemia, whereas granulocyte-platelet aggregate formation persists into the subacute phase, suggesting that they are a particularly sensitive parameter reflecting both prothrombotic and inflammatory processes after stroke.
authors.affiliation: Department of Neurology, Klinikum Ludwigshafen, Ludwigshafen, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Marquardt
authors.forename: C
authors.initials: C
authors.lastname: Anders
authors.forename: F
authors.initials: F
authors.lastname: Buggle
authors.forename: F
authors.initials: F
authors.lastname: Palm
authors.forename: P
authors.initials: P
authors.lastname: Hellstern
authors.forename: A J
authors.initials: AJ
authors.lastname: Grau
mesh_terms: D000368:Aged; D001772:Blood Cell Count; D001792:Blood Platelets / Q000378:metabolism; D002545:Brain Ischemia / Q000097:blood* / Q000150:complications; D005260:Female; D006098:Granulocytes / Q000502:physiology; D049668:History, 15th Century; D006801:Humans; D007962:Leukocytes / Q000502:physiology*; D008214:Lymphocytes / Q000502:physiology; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000502:physiology; D019007:P-Selectin / Q000097:blood; D010974:Platelet Aggregation / Q000502:physiology*; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000097:blood* / Q000209:etiology; D014057:Tomography, X-Ray Computed
chemical_list: D019007:P-Selectin