Project description:Vulvovaginal candidiasis (VVC) affects nearly ¾ of women during their lifetime and its symptoms seriously reduce quality of life. Although Candida albicans is a common commensal, it is unknown if VVC results from a commensal to pathogenic state switch, if only some strains can cause VVC, and/or if there is displacement of commensal strains with more pathogenic strains. We studied a set of VVC and Colonizing C. albicans strains to identify consistent in vitro phenotypes associated with one group or the other. We find that the strains do not differ in overall genetic profile or behavior in culture media (i.e. MLST profile, rate of growth, filamentation), but they show strikingly different behavior during their interactions with vaginal epithelial cells. Epithelial infections with VVC-derived strains yielded stronger fungal proliferation and shedding of fungi and epithelial cells. RNA-seq analysis of representative epithelial cell infections with selected pathogenic or commensal isolates identified several differentially activated epithelial signaling pathways, including the integrin, ferroptosis and type I interferon pathways; the latter has been implicated in damage protection. The type I interferon pathway is activated more by the Colonizing strains, while type I interferon inhibition selectively increases fungal shedding of only the colonizing fungi. These data suggest that VVC strains may intrinsically have more pathogenic potential via differential elicitation of epithelial responses, including type I interferon pathway. Therefore, it may be possible to evaluate pathogenic potential in vitro to refine VVC diagnosis.
Project description:Vulvovaginal candidiasis (VVC) is a common mucosal infection caused by Candida albicans, characterized by inflammation and disruption of epithelial immunity. Probiotic therapy has emerged as a promising approach for managing VVC by modulating host immune responses and enhancing mucosal defenses. In this study, we investigated the therapeutic potential of Lactobacillus salivarius HHuMin-U (HMU) against VVC using in vitro and in vivo models. HMU treatment enhanced the expression of antimicrobial peptides (AMPs) such as DEFB1 and S100A8 and modulated cytokine production (e.g., IL-6, IL-8) in vaginal epithelial cells. Furthermore, RNA sequencing of HMU-treated VK2/E6E7 cells revealed significant transcriptional changes, including upregulation of epithelial barrier function and immune-enhancing pathways. Gene Set Enrichment Analysis (GSEA) identified the NF-κB pathway as a critical regulator of HMU-induced immunity. In vivo, HMU administration significantly reduced fungal burden, mitigated tissue inflammation, and improved epithelial integrity in a murine model of VVC. The sequencing data presented in this report provide a comprehensive transcriptomic landscape of HMU-treated vaginal epithelial cells and offer insights into its underlying mechanisms. These findings support the therapeutic potential of HMU as a probiotic agent for VVC management.
Project description:A lactobacilli dominated microbiota in most pre and post-menopausal women is an indicator of vaginal health. A Nugent scoring system serves as a proxy for determining the ratio of lactobacilli to other vaginal inhabitants where a high score usually represents a diseased state, whilst an intermediate score represents a warning zone. The objective of this double blinded, placebo-controlled crossover study was to evaluate in 14 post-menopausal women with an intermediate score, the effect of vaginal administration of probiotic L. rhamnosus GR-1 and L. reuteri RC-14 on the microbiota and host response. The probiotic treatment did not result in changes to clinical parameters such as dryness, irritation and comfort, compared to when placebo was applied. Analysis using 16S rRNA sequencing and metabolomics profiling revealed that the proportional abundance of Lactobacillus was increased following probiotic administration as compared to placebo, which was weakly associated with an increase in lactate levels. Analysis of host responses by microarray showed the probiotics had an immune-modulatory response and multiplex cytokine analysis showed up-regulation of IL-5. This is the first study to use an interactomic approach for the study of vaginal probiotic administration in post-menopausal women. It shows that in some cases multifaceted approaches are required to detect the subtle trigger molecular changes induced by the host to instillation of probiotic strains. A total of 35 total RNA samples extracted from vaginal brushes were analyzed on Affymetrix Gene 2.0 ST arrays from 14 Participants collected over multiple visits including administration of either a probiotic supplement or placebo control.