Effects of voriconazole on Cryptococcus neoformans

David Van Duin, Wendy Cleare, Oscar Zaragoza, Arturo Casadevall, Joshua D. Nosanchuk

Research output: Contribution to journalArticle

54 Citations (Scopus)

Abstract

Voriconazole is a broad-spectrum triazole that offers extended activity against molds and yeasts that are not susceptible to earlier azole-type drugs. Recent studies indicate that melanization can severely reduce the susceptibility of certain antifungal drugs, but there is no information as to whether voriconazole is vulnerable to this effect. The activity of voriconazole on C. neoformans was assessed by MIC analysis and time-kill assays for melanized and nonmelanized cells. Cell morphology, capsule release, and phagocytosis of C. neoformans were studied in the presence or absence of subinhibitory concentrations of voriconazole. Voriconazole was fungicidal at concentrations of ≥8 μg/ml in vitro against the strains of C. neoformans examined, and its efficacy was not diminished by melanization. Cells grown in subinhibitory concentrations of voriconazole had smaller cellular and capsular volumes than cells grown in the absence of drug. The induction of the capsule by serum was not affected by voriconazole. Cells grown in subinhibitory concentrations of voriconazole released their capsule and were phagocytosed at rates comparable with yeast grown without the antifungal. The high activity of voriconazole against both melanized and nonmelanized cells results suggest that voriconazole may be a particularly valuable drug for cryptococcosis.

Original languageEnglish (US)
Pages (from-to)2014-2020
Number of pages7
JournalAntimicrobial Agents and Chemotherapy
Volume48
Issue number6
DOIs
StatePublished - Jun 2004

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Cryptococcus neoformans
Capsules
Phagocytosis
Pharmaceutical Preparations
Yeasts
Voriconazole
Cryptococcosis
Azoles
Triazoles
Cell Size
Fungi

ASJC Scopus subject areas

  • Pharmacology (medical)

Cite this

Effects of voriconazole on Cryptococcus neoformans. / Van Duin, David; Cleare, Wendy; Zaragoza, Oscar; Casadevall, Arturo; Nosanchuk, Joshua D.

In: Antimicrobial Agents and Chemotherapy, Vol. 48, No. 6, 06.2004, p. 2014-2020.

Research output: Contribution to journalArticle

Van Duin, David ; Cleare, Wendy ; Zaragoza, Oscar ; Casadevall, Arturo ; Nosanchuk, Joshua D. / Effects of voriconazole on Cryptococcus neoformans. In: Antimicrobial Agents and Chemotherapy. 2004 ; Vol. 48, No. 6. pp. 2014-2020.
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