Effect of granulocyte-macrophage colony-stimulating factor on candidacidal activity of neutrophils, monocytes or monocyte-derived macrophages and synergy with fluconazole.

The effect of in-vitro granulocyte-macrophage colony-stimulating factor (GM-CSF) treatment of neutrophils, monocytes or monocyte-derived macrophages (MDM) on candidacidal activity was tested. Synergy of effector cells with fluconazole (FCZ) for enhanced killing was also investigated. Incubation of neutrophils with GM-CSF 0.67 microg/L plus Candida albicans Sh27 for 24 h significantly increased candidacidal activity (36% versus 74%). Synergy with FCZ for killing was also significantly increased from 93% to 97% when neutrophils were incubated with GM-CSF. Monocytes cultured with GM-CSF and C. albicans for 24 h had significantly increased fungistatic activity compared to controls and synergy with FCZ for killing was significantly enhanced from 40% to 59%. Monocytes cultured for 3 days with GM-CSF had increased fungistatic activity compared to control MDM and showed synergy with FCZ for significantly enhanced killing (46%) compared to control MDM (12%).