Aspergillus galactosaminogalactan mediates adherence to host constituents and conceals hyphal β-glucan from the immune system.

Autor: Gravelat FN; Departments of Microbiology and Immunology, Medicine, McGill University, Montréal, Québec, Canada., Beauvais A, Liu H, Lee MJ, Snarr BD, Chen D, Xu W, Kravtsov I, Hoareau CM, Vanier G, Urb M, Campoli P, Al Abdallah Q, Lehoux M, Chabot JC, Ouimet MC, Baptista SD, Fritz JH, Nierman WC, Latgé JP, Mitchell AP, Filler SG, Fontaine T, Sheppard DC
Jazyk: angličtina
Zdroj: PLoS pathogens [PLoS Pathog] 2013; Vol. 9 (8), pp. e1003575. Date of Electronic Publication: 2013 Aug 22.
DOI: 10.1371/journal.ppat.1003575
Abstrakt: Aspergillus fumigatus is the most common cause of invasive mold disease in humans. The mechanisms underlying the adherence of this mold to host cells and macromolecules have remained elusive. Using mutants with different adhesive properties and comparative transcriptomics, we discovered that the gene uge3, encoding a fungal epimerase, is required for adherence through mediating the synthesis of galactosaminogalactan. Galactosaminogalactan functions as the dominant adhesin of A. fumigatus and mediates adherence to plastic, fibronectin, and epithelial cells. In addition, galactosaminogalactan suppresses host inflammatory responses in vitro and in vivo, in part through masking cell wall β-glucans from recognition by dectin-1. Finally, galactosaminogalactan is essential for full virulence in two murine models of invasive aspergillosis. Collectively these data establish a role for galactosaminogalactan as a pivotal bifunctional virulence factor in the pathogenesis of invasive aspergillosis.
Databáze: MEDLINE