Recombinant human G-CSF and GM-CSF prime human neutrophils for superoxide production through different signal transduction mechanisms.
Recombinant human granulocyte-colony stimulating factor (G-CSF) and recombinant human granulocyte/macrophage-colony stimulating factor (GM-CSF) stimulate neutrophil production from precursors in the marrow and enhance granulocyte functions in vitro. We studied the effects of G-CSF and GM-CSF on neutrophil superoxide production and secretion. G-CSF and GM-CSF alone stimulated neither superoxide production nor secretion, but both agents primed neutrophils for superoxide production stimulated by either N-formylmethionyl-leucyl-phenylalanine (FMLP) or ionomycin. Optimal priming occurred with G-CSF at 5.3 ng/ml for 20 minutes and for GM-CSF at 1 ng/ml for 60 minutes. Priming by GM-CSF was more readily inhibited by the tyrosine kinase inhibitor ST638 but was unaffected by staurosporine. Conversely, G-CSF priming was inhibited by staurosporine but not by ST638. Neither protein kinase C translocation nor increased protein kinase C activity, however, were observed after G-CSF/GM-CSF treatment. Priming by G-CSF and GM-CSF was sensitive to pertussis toxin, suggesting the involvement of guanine nucleotide-binding proteins (G-proteins). Neutrophils from three siblings with cyclic neutropenia were studied to observe the effects of G-CSF treatment on neutrophil function in vivo; sibling 1 and sibling 2 were treated with G-CSF for 6 months, but sibling 3 was not in the treatment group. Compared with neutrophils from normal donors, neutrophils from sibling 1 and sibling 2 were primed in vivo for superoxide release stimulated by either ionomycin or FMLP. Superoxide released by neutrophils from sibling 3 was similar to control cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Balazovich
K J
KJ
Department of Pediatrics, University of Michigan, Ann Arbor 48109-0684.
Almeida
H I
HI
Boxer
L A
LA
D000470:Alkaloids / Q000494:pharmacology; D002934:Cinnamates / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D019204:GTP-Binding Proteins / Q000502:physiology; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D015759:Ionomycin / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D047428:Protein Kinase Inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011994:Recombinant Proteins; D016897:Respiratory Burst / Q000187:drug effects*; D015398:Signal Transduction; D019311:Staurosporine; D013440:Sulfides / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism*
D000470:Alkaloids; D002934:Cinnamates; D047428:Protein Kinase Inhibitors; D011994:Recombinant Proteins; D013440:Sulfides; C060747:ST 638; D013481:Superoxides; D016179:Granulocyte Colony-Stimulating Factor; D015759:Ionomycin; D009240:N-Formylmethionine Leucyl-Phenylalanine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011505:Protein-Tyrosine Kinases; D019204:GTP-Binding Proteins; D019311:Staurosporine