title: O-glycosylation in cell wall proteins in Scedosporium prolificans is critical for phagocytosis and inflammatory cytokines production by macrophages.
abstract: In this study, we analyze the importance of O-linked oligosaccharides present in peptidorhamnomannan (PRM) from the cell wall of the fungus Scedosporium prolificans for recognition and phagocytosis of conidia by macrophages. Adding PRM led to a dose-dependent inhibition of conidia phagocytosis, whereas de-O-glycosylated PRM did not show any effect. PRM induced the release of macrophage-derived antimicrobial compounds. However, O-linked oligosaccharides do not appear to be required for such induction. The effect of PRM on conidia-induced macrophage killing was examined using latex beads coated with PRM or de-O-glycosylated PRM. A decrease in macrophage viability similar to that caused by conidia was detected. However, macrophage killing was unaffected when beads coated with de-O-glycosylated PRM were used, indicating the toxic effect of O-linked oligosaccharides on macrophages. In addition, PRM triggered TNF-α release by macrophages. Chemical removal of O-linked oligosaccharides from PRM abolished cytokine induction, suggesting that the O-linked oligosaccharidic chains are important moieties involved in inflammatory responses through the induction of TNF-α secretion. In summary, we show that O-glycosylation plays a role in the recognition and uptake of S. prolificans by macrophages, killing of macrophages and production of pro- inflammatory cytokines.
authors: Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Mariana I D S
authors: MI
authors: Xisto
authors: Departamento de Microbiologia e Parasitologia, Instituto Biomédico, UNIRIO, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Vera C B
authors: VC
authors: Bittencourt
authors: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Livia Cristina
authors: LC
authors: Liporagi-Lopes
authors: Departamento de Microbiologia e Parasitologia, Instituto Biomédico, UNIRIO, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Rosa M T
authors: RM
authors: Haido
authors: Instituto de Ciências Biomédicas, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Morena S A
authors: MS
authors: Mendonça
authors: Departamento de Bioquímica e Biologia Molecular, UFRP, Curitiba, Paraná, Brazil.
authors: Guilherme
authors: G
authors: Sassaki
authors: Campus de Xerém, Instituto de Ciências Biomédicas, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Rodrigo T
authors: RT
authors: Figueiredo
authors: Departamento de Virologia, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Maria Teresa V
authors: MT
authors: Romanos
authors: Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Eliana
authors: E
authors: Barreto-Bergter
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D005434:Flow Cytometry; D006023:Glycoproteins / Q000276:immunology / Q000378:metabolism*; D006031:Glycosylation; D016753:Interleukin-10 / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D009569:Nitric Oxide / Q000378:metabolism; D010587:Phagocytosis; D011817:Rabbits; D021681:Scedosporium / Q000502:physiology*; D013172:Spores, Fungal / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D006023:Glycoproteins; D014409:Tumor Necrosis Factor-alpha; C107788:peptido-rhamnomannan; D016753:Interleukin-10; D009569:Nitric Oxide