title: Involvement of tyrosine kinases in the activation of human peripheral blood neutrophils by granulocyte-macrophage colony-stimulating factor.
abstract: The aim of the present study is to evaluate the involvement of human neutrophil tyrosine kinase(s) in the signal transduction mechanism of granulocyte-macrophage colony-stimulating factor (GM-CSF). Stimulation of neutrophils with GM-CSF resulted in a time- and dose-dependent phosphorylation of several proteins having estimated molecular weights of approximately 40, 55, 74, 97, 118, and 155 Kd, detected by immunoblot using a monoclonal antibody directed against phosphotyrosine. GM-CSF-induced tyrosine phosphorylation was inhibited in a dose- and time-dependent manner by the tyrosine kinase inhibitor erbstatin. Using this inhibitor, we were able to correlate tyrosine phosphorylation with several functional effects of GM-CSF on human neutrophils. Pretreatment of neutrophils with erbstatin before incubation with GM-CSF completely inhibited the GM-CSF-induced intracellular alkalinization, downregulation of the leukotriene B4 receptor, enhancement of fMet-Leu-Phe-induced intracellular calcium mobilization, as well as the accumulation of mRNA for the proto-oncogene c-fos. Taken together, these data suggest that tyrosine kinase activation in human neutrophils plays a critical regulatory role in both the stimulation and priming of neutrophil function by GM-CSF.
authors.affiliation: Centre de Recherche en Inflammation, Immunologie et Rhumatologie, Université Laval, Sainte-Foy, Québec, Canada.
authors.forename: S R
authors.initials: SR
authors.lastname: McColl
authors.forename: J F
authors.initials: JF
authors.lastname: DiPersio
authors.forename: A C
authors.initials: AC
authors.lastname: Caon
authors.forename: P
authors.initials: P
authors.lastname: Ho
authors.forename: P H
authors.initials: PH
authors.lastname: Naccache
mesh_terms: D002118:Calcium / Q000097:blood; D016762:Genes, fos / Q000235:genetics; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006873:Hydroquinones / Q000494:pharmacology; D008970:Molecular Weight; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000502:physiology*; D010750:Phosphoproteins / Q000097:blood; D010766:Phosphorylation; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000097:blood*; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger / Q000096:biosynthesis; D011971:Receptors, Immunologic / Q000378:metabolism; D018102:Receptors, Leukotriene B4; D015398:Signal Transduction; D014443:Tyrosine / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D006873:Hydroquinones; C000715470:MAS1 protein, human; D010750:Phosphoproteins; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D018102:Receptors, Leukotriene B4; D019000:Phosphotyrosine; D014443:Tyrosine; D009240:N-Formylmethionine Leucyl-Phenylalanine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011505:Protein-Tyrosine Kinases; D002118:Calcium; C048212:erbstatin