Carbohydrate profiling of fungal cell wall surface glycoconjugates of Aspergillus species in brain and lung tissues using lectin histochemistry

Med Mycol. 2012 Oct;50(7):756-9. doi: 10.3109/13693786.2011.631946. Epub 2011 Nov 22.

Abstract

The aim of this study was to evaluate, through lectin histochemistry, the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surfaces of Aspergillus species in histopathological specimens of brain (n = 1) and lung (n = 6) tissues obtained during autopsy of patients diagnosed postmortem as having had invasive aspergillosis. Concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugated with horseradish peroxidase, were employed. Lectin-binding was visualized using 3,3-diaminobendizine (DAB) and hydrogen peroxide in phosphate buffer solution (PBS). We observed expression of N-acetyl-D-glucosamine and methyl-α-D-mannoside on the cell wall surfaces of all evaluated Aspergillus species, while the expression of L-fucose and D-galactose demonstrated inter and intra-specific variations. The results obtained from this study indicate that the use of WGA and Con A lectins permits visualization of Aspergillus structures such as hyphae, conidial heads and conidia in histopathological specimens of brain and lung tissues.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aspergillosis / microbiology*
  • Aspergillus / chemistry*
  • Aspergillus / isolation & purification
  • Autopsy
  • Brain / microbiology
  • Carbohydrates / analysis*
  • Cell Wall / chemistry*
  • Female
  • Glycoconjugates / analysis*
  • Histocytochemistry / methods
  • Humans
  • Lectins*
  • Lung / microbiology
  • Male
  • Middle Aged
  • Mycology / methods

Substances

  • Carbohydrates
  • Glycoconjugates
  • Lectins