Isolate-dependent growth, virulence, and cell wall composition in the human pathogen Aspergillus fumigatus

PLoS One. 2014 Jun 19;9(6):e100430. doi: 10.1371/journal.pone.0100430. eCollection 2014.

Abstract

The ubiquitous fungal pathogen Aspergillus fumigatus is a mediator of allergic sensitization and invasive disease in susceptible individuals. The significant genetic and phenotypic variability between and among clinical and environmental isolates are important considerations in host-pathogen studies of A. fumigatus-mediated disease. We observed decreased radial growth, rate of germination, and ability to establish colony growth in a single environmental isolate of A. fumigatus, Af5517, when compared to other clinical and environmental isolates. Af5517 also exhibited increased hyphal diameter and cell wall β-glucan and chitin content, with chitin most significantly increased. Morbidity, mortality, lung fungal burden, and tissue pathology were decreased in neutropenic Af5517-infected mice when compared to the clinical isolate Af293. Our results support previous findings that suggest a correlation between in vitro growth rates and in vivo virulence, and we propose that changes in cell wall composition may contribute to this phenotype.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aspergillosis / complications
  • Aspergillosis / microbiology
  • Aspergillosis / pathology
  • Aspergillus fumigatus / cytology
  • Aspergillus fumigatus / growth & development
  • Aspergillus fumigatus / isolation & purification*
  • Aspergillus fumigatus / pathogenicity*
  • Cell Wall / metabolism*
  • Chitin / metabolism
  • Colony Count, Microbial
  • Disease Models, Animal
  • Humans
  • Mice, Inbred BALB C
  • Neutropenia / complications
  • Neutropenia / microbiology
  • Neutropenia / pathology
  • Pneumonia / complications
  • Pneumonia / microbiology
  • Pneumonia / pathology
  • Virulence
  • beta-Glucans / metabolism

Substances

  • beta-Glucans
  • Chitin

Grant support

This research was supported by IUSM-TH start-up funds. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.