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bioRxiv · 10.1101/2022.12.14.520265

COVID-19 Associated Pulmonary Aspergillosis isolates are genomically diverse but similar to each other in their responses to infection-relevant stresses

Abstract

Secondary infections caused by the pulmonary fungal pathogen Aspergillus fumigatus are a significant cause of mortality in patients with severe Coronavirus Disease 19 (COVID-19). Even though epithelial cell damage and aberrant cytokine responses have been linked with susceptibility to COVID-19 associated pulmonary aspergillosis (CAPA), little is known about the mechanisms underpinning co-pathogenicity. Here, we analysed the genomes of 11 A. fumigatus isolates from patients with CAPA in three centres from different European countries. CAPA isolates did not cluster based on geographic origin in a genome-scale phylogeny of representative A. fumigatus isolates. Phenotypically, CAPA isolates were more similar to the A. fumigatus A1160 reference strain than to the Af293 strain when grown in infection-relevant stresses; except for interactions with human immune cells wherein macrophage responses were similar to those induced by the Af293 reference strain. Collectively, our data indicates that CAPA isolates are genomically diverse but are more similar to each other in their responses to infection-relevant stresses. A larger number of isolates from CAPA patients should be studied to identify genetic drivers of co-pathogenicity in patients with COVID-19. ImportanceCoronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) has been globally reported as a life-threatening complication in some patients with severe COVID-19. Most of these infections are caused by the environmental mould Aspergillus fumigatus which ranks third in the fungal pathogen priority list of the WHO. However, little is known about the molecular epidemiology of Aspergillus fumigatus CAPA strains. Here, we analysed the genomes of 11 A. fumigatus isolates from patients with CAPA in three centres from different European countries and, carried out phenotypic analyses with a view to understand the pathophysiology of the disease. Our data indicates that A. fumigatus CAPA isolates are genomically diverse but are more similar to each other in their responses to infection-relevant stresses.

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BibTeXRIS

Mead, M. E., Alves de Castro, P., Steenwyk, J. B., Gangneux, J.-P., Hoenigl, M., Prattes, J., Rautemaa-Richardson, R., Guegan, H., Moore, C. B., Lass-Floerl, C., Reizine, F., Valero, C., van Rhijn, N., Bromley, M. J., Rokas, A., Goldman, G. H., Gago, S.. 2022-12-15. COVID-19 Associated Pulmonary Aspergillosis isolates are genomically diverse but similar to each other in their responses to infection-relevant stresses. https://doi.org/10.1101/2022.12.14.520265

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