title: Respiratory burst activity of polymorphonuclear cells is dependent on the cell preparation technique.
abstract: BACKGROUND
  Controversial results have been reported regarding the effect of anaesthetics on superoxide anion production during the respiratory burst (RB) of polymorphonuclear cells (PMN). The differences could be caused by the cell preparation methods and the aim of this study was to compare two techniques.
  
  
  METHODS
  RB activity was measured in cell suspensions isolated with the single-step Ficoll procedure and in unfractionated whole blood. Two concentrations of propofol (therapeutic and 10-fold of this, 6 microg ml-1 or 60 microg ml-1) were investigated after cell preparation with both methods. RB was stimulated with Escherichia coli (E. coli), phorbol 12-myristate 13-acetate (PMA) or N-formyl-methionyl-leucyl-phenylalanine (fMLP) and measured by means of fluorescence intensity in a flow cytometer.
  
  
  RESULTS
  The percentage of PMNs in whole blood which generate superoxide anions in response to fMLP was significantly lower (2.5 +/- 0.7%; mean +/- SEM) than that in Ficoll isolated cell suspensions (15.1 +/- 1.7%). Incubation with propofol led to a concentration-related decrease of RB activity in Ficoll separated PMNs after both PMA and fMLP stimulation. No significant effect of propofol was observed on the RB in PMA stimulated whole blood samples.
  
  
  CONCLUSIONS
  The results suggest that the influence of cell preparation methods should be considered when the in vitro effects of anaesthetics on PMN functions are studied with flow cytometric methods.
authors.affiliation: Department of Anaesthesiology, Peking Union Medical College Hospital, Eastern location, Beijing, China. zhaojing@hotmail.com
authors.forename: J
authors.initials: J
authors.lastname: Zhao
authors.forename: B
authors.initials: B
authors.lastname: Juettner
authors.forename: D
authors.initials: D
authors.lastname: Scheinichen
authors.forename: K
authors.initials: K
authors.lastname: Jaeger
authors.forename: J
authors.initials: J
authors.lastname: Heine
authors.forename: S
authors.initials: S
authors.lastname: Piepenbrock
mesh_terms: D018686:Anesthetics, Intravenous; D001799:Blood Sedimentation; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D003584:Cytological Techniques; D004926:Escherichia coli; D005362:Ficoll; D006801:Humans; D066298:In Vitro Techniques; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000502:physiology*; D010587:Phagocytosis; D015742:Propofol / Q000494:pharmacology; D016897:Respiratory Burst / Q000502:physiology*; D013481:Superoxides / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D018686:Anesthetics, Intravenous; D013481:Superoxides; D005362:Ficoll; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013755:Tetradecanoylphorbol Acetate; D015742:Propofol