title: Neutrophils activated by granulocyte colony-stimulating factor suppress tumor necrosis factor-alpha release from monocytes stimulated by endotoxin.
abstract: We investigated the in vitro effects of granulocyte colony-stimulating factor (G-CSF) on tumor necrosis factor-alpha (TNF-alpha) release from monocytes. Peripheral blood monocytes and neutrophils were obtained from healthy donors (n = 8). Neutrophils alone, neutrophils plus monocytes, and monocytes alone were incubated with and without G-CSF (10 ng/ml) and were studied for TNF-alpha release; monocytes subsequently were stimulated by endotoxin (lipopolysaccharide [LPS] at 10 and 1,000 ng/ml). Neutrophils alone did not produce TNF-alpha after LPS stimulation irrespective of G-CSF treatment. TNF-alpha release from monocytes was suppressed significantly by pretreatment with G-CSF in the presence of neutrophils (P < 0.01). Suppression of TNF-alpha release after LPS was not observed when monocytes were preincubated with G-CSF in the absence of neutrophils. TNF-alpha release from monocytes stimulated by LPS was not inhibited when monocytes were incubated with the supernatant from G-CSF-activated neutrophils. Pretreatment with G-CSF inhibited intracellular TNF-alpha production, as measured by flow cytometry, of monocytes stimulated by LPS (P < 0.05). These data suggest that neutrophils activated by G-CSF directly suppress TNF-alpha release from monocytes stimulated by LPS.
authors.affiliation: Department of Medicine, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Terashima
authors.forename: K
authors.initials: K
authors.lastname: Soejima
authors.forename: Y
authors.initials: Y
authors.lastname: Waki
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
authors.forename: S
authors.initials: S
authors.lastname: Fujishima
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: A
authors.initials: A
authors.lastname: Ishizaka
authors.forename: M
authors.initials: M
authors.lastname: Kanazawa
mesh_terms: D000328:Adult; D002450:Cell Communication; D002469:Cell Separation; D004347:Drug Interactions; D004731:Endotoxins / Q000494:pharmacology*; D005434:Flow Cytometry; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism*; D018375:Neutrophil Activation / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D004731:Endotoxins; D014409:Tumor Necrosis Factor-alpha; D016179:Granulocyte Colony-Stimulating Factor