title: Molecular basis of interferon-gamma and lipopolysaccharide enhancement of phagocyte respiratory burst capability. Studies on the gene expression of several NADPH oxidase components.
abstract: In this study, we analyzed the expression of genes encoding for components of the phagocyte superoxide anion-generating system in human phagocytes treated with interferon-gamma (IFN-gamma) or lipopolysaccharide (LPS). Human neutrophils express high levels of the 47-kDa cytosolic factor (p47-phox), which are down-regulated after treatment with IFN-gamma, but not with LPS. On the contrary, the steady-state levels of the heavy chain subunit of cytochrome b558 (gp91-phox) were increased by IFN-gamma and LPS in human monocyte-derived macrophages and neutrophils in a time- and dose-dependent fashion, whereas cytochrome b558 light chain subunit (p22-phox) mRNA was not influenced by either agent. Studies on post-transcriptional regulation at the level of mRNA stability indicate that, in neutrophils, IFN-gamma has no influence on gp91-phox and p47-phox mRNA half-lives. The content of the two cytochrome b558 subunits was quantified by enzyme-linked immunosorbent assay, which revealed that, in neutrophils, gp91-phox levels doubled after 4 h of treatment with IFN-gamma or LPS. Monocyte/macrophage maturation was associated with a gradual decrease in gp91-phox mRNA and protein levels, which were both restored by treatment with IFN-gamma for 24-48 h. These results suggest that induction of the gp91-phox gene and protein product by IFN-gamma or LPS is an important requirement in the mechanism of the enhancement of neutrophil and macrophage oxidative metabolism.
authors.affiliation: Institute of General Pathology, University of Verona, Italy.
authors.forename: M A
authors.initials: MA
authors.lastname: Cassatella
authors.forename: F
authors.initials: F
authors.lastname: Bazzoni
authors.forename: R M
authors.initials: RM
authors.lastname: Flynn
authors.forename: S
authors.initials: S
authors.lastname: Dusi
authors.forename: G
authors.initials: G
authors.lastname: Trinchieri
authors.forename: F
authors.initials: F
authors.lastname: Rossi
mesh_terms: D002478:Cells, Cultured; D003573:Cytochrome b Group / Q000097:blood / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D046911:Macromolecular Substances; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology / Q000502:physiology; D009247:NADH, NADPH Oxidoreductases / Q000097:blood / Q000235:genetics*; D019255:NADPH Oxidases; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics; D011994:Recombinant Proteins; D013481:Superoxides / Q000097:blood*
chemical_list: D003573:Cytochrome b Group; D008070:Lipopolysaccharides; D046911:Macromolecular Substances; D012333:RNA, Messenger; D011994:Recombinant Proteins; D013481:Superoxides; D007371:Interferon-gamma; C036888:cytochrome b558; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases