Sialidases activity in the cervicovaginal fluid is associated with changes in bacterial components of Lactobacillus-deprived microbiota - Ferreira, Carolina Tafner; Marconi, Camila; Ravel, Jacques; Parada, Cristina Maria Garcia de Lima [UNESP]; Silva, Márcia Guimarães da [UNESP] (My University, 2021)
Introduction: Sialidases activity in the cervicovaginal fluid (CVF) is associated with microscopic findings of bacterial vaginosis (BV). Sequencing bacterial 16S rRNA gene in vaginal samples has revealed that the majority of microscopic BV cases fits into vaginal community-state type IV (CST IV), which was named molecular-BV. Bacterial vaginosis-associated bacterial species, as Gardnerella spp., are the sources of CVF sialidases. These hydrolases lead to impairment of local immunity through cervical mucus and immunoglobulin A degradation. However, the impact of CVL sialidase on microbiota components and diversity remains unknown. Objective: To assess if CVF sialidase activity is associated with changes in bacterial components of CST IV. Methods: One hundred forty women were cross-sectionally enrolled. Presence of molecular-BV (CST IV) was assessed by V3-V4 16S rRNA sequencing (Illumina). Fluorometric assays were performed using 2‐(4‐methylumbelliferyl)‐α‐D‐N‐acetylneuraminic acid (MUAN) for measuring sialidases activity in CVF samples. Linear discriminant analysis effect size (LEfSe) was performed to identify the differently enriched bacterial taxa in molecular-BV according to status of CVF sialidase activity. Results: Forty-four participants (31.4%) had molecular-BV, of which 30 (68.2%) had sialidases activity at detectable levels. A total of 24 bacterial taxa were enriched in the presence of sialidase activity, while just two taxa were enriched in sialidases-negative samples. Conclusion: Sialidases activity in molecular-BV is associated with changes in bacterial components of the local microbiome. This association should be further investigated, since it may result in diminished the local defenses against pathogens.
Keywords: Vaginal microbiota; Bacterial vaginosis; Sialidases