Investigation of the basis of virulence in serotype A strains of Cryptococcus neoformans from apparently immunocompetent individuals.

Journal Article

Cryptococcus neoformans serotype A strains commonly infect immunocompromised patients to cause fungal meningitis. To understand the basis of serotype A cryptococcal infections in apparently immunocompetent patients, we tested two hypotheses: the strains were naturally occurring hypervirulent pkr1 (PKA regulatory subunit) mutants, or the strains were hybrids with C. neoformans var. gattii strains that normally infect immunocompetent individuals. Analysis of clinical isolates obtained from apparently immunocompetent individuals from three continents revealed that none were pkr1 mutants, but several exhibited phenotypes consistent with perturbations in cAMP signaling. Additionally, none of the strains were unusual hybrids with gattii strains. Except for one strain that was an AD hybrid, all others were serotype A (var. grubii) isolates. Taken together, our findings indicate that the ability of these clinical isolates to infect apparently normal individuals may be attributable to mutations other than pkr1 and/or underlying immune system impairment in patients.

Full Text

Duke Authors

Cited Authors

  • D'Souza, CA; Hagen, F; Boekhout, T; Cox, GM; Heitman, J

Published Date

  • August 2004

Published In

Volume / Issue

  • 46 / 2

Start / End Page

  • 92 - 102

PubMed ID

  • 15150669

International Standard Serial Number (ISSN)

  • 0172-8083

Digital Object Identifier (DOI)

  • 10.1007/s00294-004-0511-y

Language

  • eng

Conference Location

  • United States