Granulocyte Colony-Stimulating Factor Enhances the Extracellular Emission of Reactive Oxygen from Neutrophils Stimulated with Formylmethionylleucylphenylalanine

Pretreatment of neutrophils with granulocyte colony-stimulating factor (G-CSF) enchanced luminol-dependent chemiluminescence emission by the stimulation of formylmethionylleucylphenylalanine (FMLP), opsonized zymosan, and zymosan. The intensity of the priming effects was in the following order: FMLP > zymosan > opsonized zymosan. However, the priming effect of G-CSF was not detected by the stimulation of phorbol myristate acetate. The reaction curve with the stimulation of FMLP showed a bimodal shape, and the elevation of the first peak by the priming effect was further prominent in comparison with the elevation of the second peak. This indicates that G-CSF mainly enhances the extracellular release of oxygen radicals in response to the stimulation with FMLP. This is the first report investigating intra- and extracellular events in chemiluminescence reaction of neutrophils primed with G-CSF.