title: The effects of cytokines, platelet activating factor, and arachidonate metabolites on C3b receptor (CR1, CD35) expression and phagocytosis by neutrophils.
abstract: The cytokines tumor necrosis factor alpha (TNF alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and interleukin 1 (IL 1) all caused an upregulation of C3b receptors (CR1) on neutrophils that ranged from around 76% (G-CSF and IL 1) to 93% (TNF alpha and GM-CSF) of the upregulation obtained by pretreatment of the neutrophils with the chemotactic peptide FMLP. However, only TNF alpha and G-CSF caused a significant increase in phagocytosis of opsonized microspheres. Platelet derived growth factor, interleukin 2, and transforming growth factor beta had no effect on either of these parameters. The mediators platelet activating factor (PAF) and leukotriene B4 (LTB4) both caused a large upregulation of CR1 (93% and 80%, respectively, of the FMLP-mediated value); however, only PAF caused a significant enhancement of phagocytosis by the neutrophils. Prostaglandin E2 and thromboxane B2 had no effect on these parameters. Considerable individual variation was observed among some of the untreated and mediator-treated neutrophil preparations regarding CR1 expression and phagocytosis. The upregulation of CR1 and associated increase in phagocytic capacity of neutrophils caused by certain cytokines and other mediators may be important in host defense. Also the lack of enhancement of phagocytosis accompanying an upregulation of CR1 is unusual and may have important implications regarding the cellular mechanisms of phagocytosis by neutrophils.
authors.affiliation: Department of Molecular Genetics, University of Cincinnati Medical Center, Ohio.
authors.forename: J D
authors.initials: JD
authors.lastname: Ogle
authors.forename: J G
authors.initials: JG
authors.lastname: Noel
authors.forename: R M
authors.initials: RM
authors.lastname: Sramkoski
authors.forename: C K
authors.initials: CK
authors.lastname: Ogle
authors.forename: J W
authors.initials: JW
authors.lastname: Alexander
mesh_terms: D015703:Antigens, CD / Q000502:physiology; D001095:Arachidonic Acids / Q000494:pharmacology*; D003179:Complement C3b / Q000502:physiology; D016207:Cytokines / Q000494:pharmacology*; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007975:Leukotriene B4 / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D010587:Phagocytosis / Q000187:drug effects*; D010972:Platelet Activating Factor / Q000494:pharmacology*; D011951:Receptors, Complement / Q000187:drug effects / Q000502:physiology*; D017463:Receptors, Complement 3b; D011994:Recombinant Proteins / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D015703:Antigens, CD; D001095:Arachidonic Acids; D016207:Cytokines; D007375:Interleukin-1; D010972:Platelet Activating Factor; D011951:Receptors, Complement; D017463:Receptors, Complement 3b; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D016179:Granulocyte Colony-Stimulating Factor; D007975:Leukotriene B4; D009240:N-Formylmethionine Leucyl-Phenylalanine; D003179:Complement C3b; D016178:Granulocyte-Macrophage Colony-Stimulating Factor