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 acids (PGEF), was evaluated for its in vitro effect on phagocytosis and respiratory burst activity of isolated human neutrophils using flow cytometric assay. 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. After 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 DGMO emulsion left little influence on complement receptor type three (CR3) that is associated with phagocytosis. On the other hand, oxidation of hydroethidine, which was used as an indicator of intracellular generation of reactive oxygen species (mainly for superoxide anion), was significantly inhibited by DGMO over 1 mg/ml. However, this phenomenon was not seen in DGMO-treated neutrophils when DGMO was removed after incubation. The present data suggest that DGMO does not affect phagocytosis of human neutrophils but down-regulates respiratory burst activity.