Oxygen-dependent Killing of Staphylococcus aureus by Human Neutrophils

Abstract

Luminol-dependent chemiluminescence was used as a monitor of reactive oxidant generation during phagocytosis of Staphylococcus aureus by human neutrophils. Reactive oxidants play a crucial role in the killing of this organism because : (a) S. aureus was killed most rapidly when the rate of increase of chemiluminescence was greatest; (b) neutrophils which had been activated to generate reactive oxidants by re-aeration of anaerobic suspensions killed this bacterium more efficiently than control suspensions; and (c) neutrophils from a patient with chronic granulomatous disease could neither generate reactive oxidants nor kill S . aureus.

Activation of neutrophils by soluble and insoluble immunoglobulin aggregates from synovial fluid of patients with rheumatoid arthritis.

“…The mean age was 55 (21-80) years and the mean duration of disease was 7-6 (0. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] cells/ml. Control suspensions contained no further additions and primed neutrophils were supplemented with 50 U/ml recombinant (r) GM-CSF.…”

“…Superoxide production was measured as the rate of superoxide dismutase inhibitable cytochrome c reduction. ' [15][16][17][18][19][20] minutes after addition ( fig 1A). In parallel experiments, we showed that such synovial fluids failed to stimulate the secretion of 02- (fig 1 B).…”

Chemiluminescence and superoxide production in Acanthamoeba castellanii: free radicals generated during oxidative stress

“…Superoxide anion (Oy) production by cell suspensions in PBS (phosphate-buffered saline: 0.9% NaCl; 10 mMpotassium phosphate buffer; pH 7.4) was measured by the method of Babior et al (1973) using a Perkin-Elmer Lambda 5 spectrophotometer: suspensions (1 ml) contained 1 x lo6 cells, 75 pM-cytochrome c, and superoxide dismutase, as indicated. Chemiluminescence measurements were performed in 10 ml suspensions containing either 10 pMluminol or 50 pM-lucigenin in a specially constructed 'open' system in which O2 measurements could be made simultaneously with chemiluminescence measurements (Edwards et al, 1987). In this system the O2 tensions in the gas phase (and after equilibration, those in the liquid phase) were regulated using a digital gas mixer.…”

“…A. castellanii were grown to the mid-exponential phase (2 x lo6 cells ml-l), harvested and suspended in PBS at a concentration of 1.6 x lo6 cells m1-l. Ten millilitres of this suspension was placed in the 'open' O2 electrode/chemiluminescence system (Edwards et al, 1987), which was maintained at 30 "C, and lucigenin was added to 50 p~ (final concn). At the point indicated (1) 1 mM-sodium cyanide was added.…”

“…The precise molecular processes that result in photon emission during oxidation of these probes are unknown, but the former measures peroxidase/H202-dependent reactions whereas the latter appears to be dependent upon 0, and/or H 2 0 2 formation (Edwards, 1987). The OF-generating oxidase of A .…”