Modifications of the composition of the hyphal outerlayer of Aspergillus fumigatus affects HUVEC inflammatory and immune response

ABSTRACT: Aspergillus fumigatus is an angioinvasive fungal pathogen and the main etiologic agent causing invasive aspergillosis. Upon contact with human umbilical vein endothelial cells (HUVECs), this fungus induces cellular injury, inflammatory response and a pro-thrombotic phenotype. The pathogen molecules involved in this processes are however still unknown. A. fumigatus hyphae have been shown to produce, both in vivo and in vitro, an extracellular matrix composed of galactomannan, galactosaminogalactan and α-(1,3)-glucan. The deletion of the UDP-Galp mutase results in a mutant with a very sticky phenotype, due to the increase in the galactosaminogalactan content in the cell surface. The overexpression of galactosaminogalactan in this mutant was confirmed by immunofluorescence microscopy with a monoclonal antibody. Interestingly, the adhesion of ∆ugm1 germlings to HUVECs was significantly higher in comparison to the wild type strain. The ∆ugm1 adhesion capacity was followed by an increment in the cytokine secretion and tissue factor expression by infected endothelial cells. Using a shotgun proteomic approach with label-free quantification, we were able to search and compare pathways regulated in endothelial cells challenged with A. fumigatus, wild type and ∆ugm1. The deletion of the UGM1 gene in A. fumigatus induced changes in the endothelial cell response, maily related to immune and stress responses. In addition, the purified urea soluble fraction of galactosaminogalactan was able to induce TNF-α secretion by HUVECs and also regulate coincident pathways identified in the mutant interaction condition. This work describes for the first time the impact of the modifications of the hyphal surface galactosaminogalactan on the endothelial cell responses to A. fumigatus.

INSTRUMENT(S): Synapt G2-S HDMS

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Endothelial Cell Of Umbilical Vein

SUBMITTER: Gustavo Souza  

LAB HEAD: Leila Maria Lopes Bezerra

PROVIDER: PXD002823 | Pride | 2016-06-22

REPOSITORIES: Pride