title: The effects of stem cell factor and granulocyte colony stimulating factor therapy on the activity of the neutrophil NADPH oxidase enzyme system.
abstract: BACKGROUND
  To explore the effect of cytokine therapy on the NADPH oxidase in mature myeloid cells, we isolated neutrophils from patients receiving recombinant human granulocyte colony stimulating factor (G-CSF) and recombinant human stem cell factor (SCF) and evaluated oxidase activity. All patients had relapsed neoplastic disease and were at least 3 three weeks since the last course of chemotherapy or cytokine therapy.
  
  
  METHODS
  Stimulus induced superoxide anion (O2-) production in response to PMA (200 ng/mL), fMLP (1 mumol/L), platelet activating factor (PAF, 2 mumol/L) priming of the fMLP induced response, and opsonized zymosan OZ (1 mg/mL) was measured. Polymorphonuclear leukocyte (PMN) subcellular components were prepared, after nitrogen cavitation, by separation on discontinuous sucrose gradients and NADPH oxidase activity was assessed in a SDS cell-free system.
  
  
  RESULTS
  SCF had no effect on the activity of the neutrophil oxidase. Neutrophils isolated from patients treated with G-CSF and stimulated with PMA produced less (superoxide anion) O2- after therapy. PAF priming of the fMLP induced respiratory burst was also reduced after therapy with G-CSF. Subcellular NADPH oxidase activity was reduced before cytokine therapy commenced. This activity did not improve with cytokine treatment.
  
  
  CONCLUSIONS
  It appears likely from this study that G-CSF therapy, with or without SCF, does not cause significant enhancement of neutrophil NADPH oxidase activity.
authors.affiliation: Bonfils Blood Center, Denver, CO, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Leavey
authors.forename: G
authors.initials: G
authors.lastname: Thurman
authors.forename: C
authors.initials: C
authors.lastname: Gonzalez-Aller
authors.forename: G
authors.initials: G
authors.lastname: Zerbe
authors.forename: D R
authors.initials: DR
authors.lastname: Ambruso
mesh_terms: D000328:Adult; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D019255:NADPH Oxidases / Q000378:metabolism*; D009504:Neutrophils / Q000187:drug effects* / Q000201:enzymology; D019089:Stem Cell Factor / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D019089:Stem Cell Factor; D016179:Granulocyte Colony-Stimulating Factor; D009240:N-Formylmethionine Leucyl-Phenylalanine; D019255:NADPH Oxidases; D013755:Tetradecanoylphorbol Acetate