The pH-Responsive PacC Transcription Factor of Aspergillus fumigatus Governs Epithelial Entry and Tissue Invasion during Pulmonary Aspergillosis
Autor: | Elaine Bignell, Nick D. Read, Angela M. Cheverton, Darius Armstrong-James, Eduardo A. Espeso, Markus Schrettl, Scott G. Filler, Louise A. Walker, Dan Chen, Susanne Herbst, Carol A. Munro, William C. Nierman, Laura Alcazar-Fuoli, Natalie D. Fedorova, Alberto Muñoz, Timothy C. Cairns, Margherita Bertuzzi, Hong Liu, Hubertus Haas, Shinobu Saijo, Maryam Safari |
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Přispěvatelé: | Medical Research Council (MRC) |
Rok vydání: | 2015 |
Předmět: |
QH301-705.5
Immunology Microbiology Aspergillus fumigatus Fungal Proteins Mice 1108 Medical Microbiology Virology Genetics medicine Animals Biology (General) Bovine serum albumin Molecular Biology Transcription factor biology Chemistry business.industry fungi Correction Epithelial Cells RC581-607 Hydrogen-Ion Concentration equipment and supplies biology.organism_classification Spore Biotechnology Penicillin Pulmonary aspergillosis 1107 Immunology Medical Microbiology Streptomycin biology.protein bacteria Tissue invasion Parasitology Pulmonary Aspergillosis sense organs Immunologic diseases. Allergy business 0605 Microbiology Transcription Factors medicine.drug |
Zdroj: | PLoS Pathogens PLoS pathogens, vol 11, iss 6 PLoS Pathogens, Vol 11, Iss 6, p e1004943 (2015) e1004943 |
ISSN: | 1553-7374 |
DOI: | 10.1371/journal.ppat.1004943 |
Popis: | Destruction of the pulmonary epithelium is a major feature of lung diseases caused by the mould pathogen Aspergillus fumigatus. Although it is widely postulated that tissue invasion is governed by fungal proteases, A. fumigatus mutants lacking individual or multiple enzymes remain fully invasive, suggesting a concomitant requirement for other pathogenic activities during host invasion. In this study we discovered, and exploited, a novel, tissue non-invasive, phenotype in A. fumigatus mutants lacking the pH-responsive transcription factor PacC. Our study revealed a novel mode of epithelial entry, occurring in a cell wall-dependent manner prior to protease production, and via the Dectin-1 β-glucan receptor. ΔpacC mutants are defective in both contact-mediated epithelial entry and protease expression, and significantly attenuated for pathogenicity in leukopenic mice. We combined murine infection modelling, in vivo transcriptomics, and in vitro infections of human alveolar epithelia, to delineate two major, and sequentially acting, PacC-dependent processes impacting epithelial integrity in vitro and tissue invasion in the whole animal. We demonstrate that A. fumigatus spores and germlings are internalised by epithelial cells in a contact-, actin-, cell wall- and Dectin-1 dependent manner and ΔpacC mutants, which aberrantly remodel the cell wall during germinative growth, are unable to gain entry into epithelial cells, both in vitro and in vivo. We further show that PacC acts as a global transcriptional regulator of secreted molecules during growth in the leukopenic mammalian lung, and profile the full cohort of secreted gene products expressed during invasive infection. Our study reveals a combinatorial mode of tissue entry dependent upon sequential, and mechanistically distinct, perturbations of the pulmonary epithelium and demonstrates, for the first time a protective role for Dectin-1 blockade in epithelial defences. Infecting ΔpacC mutants are hypersensitive to cell wall-active antifungal agents highlighting the value of PacC signalling as a target for antifungal therapy. |
Databáze: | OpenAIRE |
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