Oral epithelial cells distinguish between Candida species with high or low pathogenic potential through miRNA regulation

AbstractOral epithelial cells monitor microbiome composition and initiate immune response upon dysbiosis, as in case of Candida imbalances. Comparison of healthy oral epithelial cell responses revealed that the inability of C. parapsilosis to induce a robust antifungal response was due to activation of various inflammation-independent pathways, while C. albicans robustly activated inflammation cascades. Regarding posttranscriptional regulation, several miRNAs were altered by both species. For C. parapsilosis, the applied dose directly correlated with changes in transcriptomic responses. Carbohydrate metabolism, hypoxia- and cardiovascular development-related responses dominate after C. parapsilosis stimulus, whereas C. albicans altered inflammatory responses. Subsequent analyses of HIF1-α and HSC-activation pathways predicted target genes through which miRNA-dependent regulation of yeast-specific functions may occur, supporting the observed responses. Thus, C. parapsilosis is recognized as a commensal at low doses by the oral epithelium; however, increased fungal burden activates different pathways, some of which overlap with inflammatory processes induced by C. albicans.Impact statementAltered miRNA regulation discriminates between C. albicans and C. parapsilosis in human oral epithelial cells