title: Priming of neutrophils and differentiated PLB-985 cells by pathophysiological concentrations of TNF-α is partially oxygen dependent.
abstract: Activation of polymorphonuclear leukocytes (PMN) can be modulated to intermediate 'primed' states characterized by enhanced responsiveness to subsequent stimuli. We studied priming in response to TNF-α in human PMN and PLB-985 cells, a myeloid cell line differentiated to a neutrophilic phenotype (PLB-D). PMN generated reactive oxygen species (ROS) in response to TNF-α alone, and NADPH oxidase activity increased in response to stimulation with formyl-Met-Leu-Phe after priming. PLB-D cells also demonstrated priming of NADPH oxidase activity. Similar to priming by endotoxin, priming of the respiratory burst by TNF-α was predominantly oxygen dependent, with marked attenuation of ROS generation if primed anaerobically. Both PMN and PLB-D cells displayed significant increases in cell surface CD11b and gp91(phox) expression after TNF-α priming and PMN displayed activation of MAPK. In response to TNF-α priming, neither mobilization of intracellular proteins nor activation of MAPK pathways was NADPH oxidase dependent. Priming of PMN and PLB-D cells by low TNF-α concentrations enhanced chemotaxis. These data demonstrate that pathophysiological concentrations of TNF-α elicit NADPH oxidase-derived ROS and prime cells for enhanced surface protein expression, activation of p38 and ERK1/2 MAPK pathways, and increased chemotaxis. Furthermore, PLB-D cells undergo TNF-α priming and provide a genetically modifiable model to study priming mechanisms.
authors.affiliation: Division of Critical Care, Department of Pediatrics, Inflammation Program, University of Iowa and Veterans Affairs Medical Center, Iowa City, Iowa, USA.
authors.forename: A Paige Davis
authors.initials: AP
authors.lastname: Volk
authors.forename: Brieanna M
authors.initials: BM
authors.lastname: Barber
authors.forename: Kelli L
authors.initials: KL
authors.lastname: Goss
authors.forename: Jake G
authors.initials: JG
authors.lastname: Ruff
authors.forename: Christine K
authors.initials: CK
authors.lastname: Heise
authors.forename: Jessica S
authors.initials: JS
authors.lastname: Hook
authors.forename: Jessica G
authors.initials: JG
authors.lastname: Moreland
mesh_terms: D039481:CD11b Antigen / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000276:immunology; D004789:Enzyme Activation / Q000276:immunology; D006801:Humans; D020935:MAP Kinase Signaling System / Q000276:immunology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D009249:NADP / Q000235:genetics / Q000378:metabolism*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism; D018375:Neutrophil Activation; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D010100:Oxygen / Q000276:immunology / Q000378:metabolism*; D018805:Sepsis / Q000276:immunology* / Q000517:prevention & control; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D039481:CD11b Antigen; D008562:Membrane Glycoproteins; D014409:Tumor Necrosis Factor-alpha; D009249:NADP; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; D048051:p38 Mitogen-Activated Protein Kinases; D010100:Oxygen