The transcriptome of dendritic cells redraws the boundaries between pathogenicity and commensalism in yeast.

Abstract

Our immune system is constantly exposed to fungi, but it mounts a consistent, disease-related, and species-specific inflammatory response only against a few fungal species. Most of the current understanding of fungus-host interactions is based on a limited number of strains, hence neglecting the fungal intra-specific genetic and phenotypic diversity. To expand our knowledge of the spectrum of immune responses to pathogenic and non-pathogenic fungi, we compared the cytokine and transcriptional profiles of human monocyte-derived dendritic cells exposed to Aspergillus fumigatus, Candida albicans, Candida parapsilosis, and Saccharomyces cerevisiae strains. The tested species triggered common and species-specific responses, mostly resulting from the different timing of signaling pathways. Faster phagolysosome acidification was observed for pathogenic species. These results highlight the urgency to redraw the boundaries between pathogenicity and commensalism in fungi, shining a spotlight on the timing of the response, rather than solely on the genes triggered by the stimuli.