Effect of decaglycerol monooleate on phagocytosis and respiratory burst activity of human neutrophils: an in vitro study

Decaglycerol monooleate (DGMO), a type of polyglycerol esters of fatty acid s (PGEF), was evaluated for its in vitro effect on phagocytosis and respira tory burst activity of isolated human neutrophils using flow cytometric ass ay. Opsonized zymosan particles labelled with FITC (FITC-OZ) were employed as an indicator of phagocytosis. Fluorescence of FITC-OZ attached on to the surface of neutrophils was quenched by addition of trypan blue solution. A fter 10 minutes of incubation with DGMO up to a concentration of 10 mg/ml, neutrophil phagocytosis was not affected markedly. At the same time, the DG MO emulsion left little influence on complement receptor type three (CR3) t hat is associated with phagocytosis. On the other hand, oxidation of hydroe thidine, which was used as an indicator of intracellular generation of reac tive oxygen species (mainly for superoxide anion), was significantly inhibi ted by DGMO over 1 mg/ml. However, this phenomenon was not seen in DGMO-tre ated neutrophils when DGMO was removed after incubation. The present data s uggest that DGMO does not affect phagocytosis of human neutrophils but down -regulates respiratory burst activity. (C) 2000 Published by Elsevier Scien ce Ltd. All rights reserved.