Development of cytochrome b558 and oxidative metabolism in human granulocytes, monocytes and during differentiation of HL-60 and U 937 cells.
The development of cytochrome b558 (Cyt b) as determined spectrophotometrically, was investigated in human polymorphonuclear neutrophils (PMN), monocytes (MN) and during differentiation of HL-60 and U 937 cells induced by retinoic acid (RA) alone or in combination with IFN gamma. O2- release in response to a panel of stimulating agents, ie latex particles, opsonised zymosan, PMA, Con A and fMLP, was monitored by lucigenin-amplified chemiluminescence (CL). In parallel the expression of myeloperoxidase (MPO) was investigated and its catalytic activity on H2O2 related to luminol-amplified CL responses. In mature PMN and MN phagocytes, regardless of the stimulating agent, the O2- production is closely related to Cyt b but not to MPO specific contents. In differentiated HL-60 and U 937 cells, the oxidative metabolism increases in parallel with Cyt b specific contents, both being enhanced by the addition of IFN gamma to the RA treatment. However, marked differences in the O2- production intensities are observed depending on the stimulating agent tested and the state of differentiation considered. The PMA-stimulated O2- production is rather low ie 100 and 20 times less in granulocytic HL-60 and monocyto-macrophagic U 937 cells than in PMN and MN respectively. Latex, zymosan and Con A stimulated responses are close to those of MN, in monocyte-macrophagic U 937 cells. In conclusion, these data show that during differentiation; 1), Cyt b plays a critical role in O2- production; 2), the pathways leading to NADPH oxidase activation are diversely modulated following phagocyte differentiation with IFN gamma and/or with RA.
Capeillère-Blandin
C
C
INSERM U 25, CNRS UA 122, Clinique Néphrologique, Hôpital Necker, Paris, France.
Chauvet
G
G
Tresset
F
F
Descamps-Latscha
B
B
D000166:Acridines; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D003573:Cytochrome b Group / Q000096:biosynthesis*; D004789:Enzyme Activation; D006098:Granulocytes / Q000166:cytology / Q000201:enzymology; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D008163:Luminescent Measurements; D008165:Luminol; D009000:Monocytes / Q000166:cytology / Q000201:enzymology; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D019255:NADPH Oxidases; D009504:Neutrophils / Q000166:cytology / Q000201:enzymology; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000096:biosynthesis; D010586:Phagocytes / Q000166:cytology* / Q000201:enzymology*; D014212:Tretinoin; D014407:Tumor Cells, Cultured
D000166:Acridines; D003573:Cytochrome b Group; C033472:10,10'-dimethyl-9,9'-biacridinium; D014212:Tretinoin; D008165:Luminol; C036888:cytochrome b558; D006861:Hydrogen Peroxide; D009195:Peroxidase; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases