title: Cell-free activation of phagocyte NADPH-oxidase: tissue and differentiation-specific expression of cytosolic cofactor activity.
abstract: We examined a variety of tissues for the presence of cytosolic cofactor activity that would support arachidonate-dependent cell-free activation of NADPH-oxidase in isolated human neutrophil membranes. Cofactor activity was not found in cytosol isolated from erythrocytes, lymphocytes, placenta, brain, liver, or the human promyelocytic leukemic cell line HL-60. Induction of differentiation in HL-60 cells led to expression of cytosolic cofactor activity. In dimethylsulphoxide-induced HL-60 cells the level of cytosolic cofactor activity was closely correlated with phorbol myristate acetate-stimulated whole cell superoxide production. These results strongly suggest that the cytosolic cofactor is a phagocyte-specific regulatory protein of physiologic importance in NADPH-oxidase activation.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D003600:Cytosol / Q000502:physiology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004789:Enzyme Activation; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D015470:Leukemia, Myeloid, Acute; D008214:Lymphocytes / Q000378:metabolism; D051379:Mice; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D019255:NADPH Oxidases; D009504:Neutrophils / Q000378:metabolism; D010586:Phagocytes / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014018:Tissue Distribution
chemical_list: D013481:Superoxides; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D013755:Tetradecanoylphorbol Acetate; D004121:Dimethyl Sulfoxide