Comparison of Interferon-γ, Granulocyte Colony-Stimulating Factor, and Granulocyte-Macrophage Colony-Stimulating Factor for Priming Leukocyte-Mediated Hyphal Damage of Opportunistic Fungal Pathogens

Proinflammatory cytokines have been proposed as adjunctive therapeutic agents to enhance the host immune response during infections caused by opportunistic fungi. The study compared the differential in vitro priming effects of interferon-γ (IFN-γ), granulocyte colony-stimulating factor (G-CSF), and granulocyte-macrophage colony-stimulating factor (GM-CSF) on hyphal damage of opportunistic fungi mediated by isolated neutrophils (polymorphonuclear leukocytes, PMNL) and buffy coat cells (polymorphonuclear leukocytes/peripheral blood mononuclear cells, PMNL/PBMC) from healthy donors. IFN-γ (1000 U/mL) effectively primed both PMNL and PMNL/PBMC for enhanced hyphal damage of Aspergillus fumigatus, Fusarium solani, and Candida albicans. G-CSF (100 ng/mL) increased hyphal damage mediated by both PMNL and PMNL/PBMC against F. solani, and GM-CSF (100 ng/mL) augmented the antifungal activity of PMNL/PBMC against hyphal forms of both F. solani and C. albicans. IFN-γ may be superior to G-CSF or GM-CSF for enhancing the microbicidal activity of PMNL and PMNL/PBMC against opportunistic fungi.