Development of a Microarray-Based Tool To Characterize Vaginal Bacterial Fluctuations and Application to a Novel Antibiotic Treatment for Bacterial Vaginosis

Abstract

ABSTRACTThe healthy vaginal microbiota is generally dominated by lactobacilli that confer antimicrobial protection and play a crucial role in health. Bacterial vaginosis (BV) is the most prevalent lower genital tract infection in women in reproductive age and is characterized by a shift in the relative abundances ofLactobacillusspp. to a greater abundance of strictly anaerobic bacteria. In this study, we designed a new phylogenetic microarray-based tool (VaginArray) that includes 17 probe sets specific for the most representative bacterial groups of the human vaginal ecosystem. This tool was implemented using the ligase detection reaction-universal array (LDR-UA) approach. The entire probe set properly recognized the specific targets and showed an overall sensitivity of 6 to 12 ng per probe. The VaginArray was applied to assess the efficacy of rifaximin vaginal tablets for the treatment of BV, analyzing the vaginal bacterial communities of 22 BV-affected women treated with rifaximin vaginal tablets at a dosage of 25 mg/day for 5 days. Our results showed the ability of rifaximin to reduce the growth of various BV-related bacteria (Atopobium vaginae,Prevotella,Megasphaera,Mobiluncus, andSneathiaspp.), with the highest antibiotic susceptibility forA. vaginaeandSneathiaspp. Moreover, we observed an increase ofLactobacillus crispatuslevels in the subset of women who maintained remission after 1 month of therapy, opening new perspectives for the treatment of BV.