Differential susceptibility of yeast and hyphal forms of Candida albicans to macrophage-derived nitrogen-containing compounds.
Candida albicans is a dimorphic fungus capable of transition from the yeast form (Y-Candida) to the hyphal form (H-Candida). Both Y-Candida and H-Candida are known to be growth inhibited by murine macrophages (M phi) in vitro. In the present report, we demonstrate that M phi exposed to interferon gamma (IFN-gamma) plus lipopolysaccharide (LPS) show enhanced anti-Y-Candida and anti-H-Candida activities. To further investigate the phenomenon, Y-Candida and H-Candida were assessed for susceptibilities to M phi-derived supernatants. Only the growth of H-Candida, and not that of Y-Candida, is impaired by cell-free supernatants from M phi treated with IFN-gamma plus LPS. In contrast, no H-Candida growth inhibition occurs when supernatants from M phi exposed to IFN-gamma plus LPS in the presence of NG-monomethyl-L-arginine, an inhibitor of nitric oxide (NO) synthesis, are employed. Finally, supernatants from M phi incubated with sodium nitroprusside, an NO-generating agent, also show anti-H-Candida activity. In conclusion, these results indicate that H-Candida but not Y-Candida is susceptible to extracellular antifungal mechanisms employed by M phi, which likely involve stable nitrogen-containing compounds.
Blasi
E
E
Department of Biomedical Sciences, University of Modena, Italy.
Pitzurra
L
L
Puliti
M
M
Chimienti
A R
AR
Mazzolla
R
R
Barluzzi
R
R
Bistoni
F
F
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D002176:Candida albicans / Q000166:cytology* / Q000187:drug effects / Q000276:immunology*; D007371:Interferon-gamma / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000737:chemistry / Q000276:immunology*; D051379:Mice; D009024:Morphogenesis; D009569:Nitric Oxide / Q000037:antagonists & inhibitors; D017672:Nitrogen Compounds / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology; D019323:omega-N-Methylarginine
D008070:Lipopolysaccharides; D017672:Nitrogen Compounds; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D007371:Interferon-gamma; D001120:Arginine