Open AccessExploring potential of vaginal Lactobacillus isolates from South African women for enhancing treatment for bacterial vaginosis
Author(s) -
AnnaUrsula Happel,
Brian Kullin,
Hoyam Gamieldien,
Nicole Wentzel,
Chambrez Z. Zauchenberger,
Heather B. Jaspan,
Smritee Dabee,
Shaun Barnabas,
Shameem Z. Jaumdally,
Janan Dietrich,
Glenda Gray,
LindaGail Bekker,
Rémy Froissart,
JoAnn S. Passmore
Publication year - 2020
Publication title -
plos pathogens
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.719
H-Index - 206
eISSN - 1553-7374
pISSN - 1553-7366
DOI - 10.1371/journal.ppat.1008559
Subject(s) - lactobacillus crispatus , lactobacillus , microbiology and biotechnology , bacterial vaginosis , lactobacillus gasseri , gardnerella vaginalis , biology , vaginal flora , probiotic , lactobacillus reuteri , lactobacillus rhamnosus , bacteria , genetics
Antibiotics continue to be the standard-of-care for bacterial vaginosis (BV), although recurrence rates are high. Vaginal probiotics may improve durability of BV treatment, although few probiotics for vaginal health contain Lactobacillus spp. that commonly colonize the lower female genital tract. Characteristics of vaginal Lactobacillus strains from South African women were evaluated for their probiotic potential in vitro compared to strains from commercial vaginal products, including growth at varying pHs, ability to lower pH, produce D-/L-lactate and H 2 O 2 , influence growth of BV-associated Gardnerella vaginalis and Prevotella bivia , adherence to cervical cells and susceptibility to antibiotics. Fifty-seven Lactobacillus strains were purified from cervico-vaginal fluid, including L . crispatus , L . jensenii , L . gasseri , L . mucosae , and L . vaginalis . L crispatus strains grew better at pHs below 4.5 and lowered pH more effectively than other strains. Production of D-/L-lactate and H 2 O 2 varied between Lactobacillus species and strains. Lactobacillus strains generally inhibited P . bivia more uniformly than G . vaginalis isolates. All vaginal Lactobacillus isolates were resistant to metronidazole while susceptibility to clindamycin varied. Furthermore, vaginal Lactobacillus strains tended to be broadly susceptible to penicillin, amoxicillin, rifampicin and rifabutin. Whole-genome-sequencing of five of the best-performing vaginal Lactobacillus strains confirmed their likely safety, due to antimicrobial resistance elements being largely absent, while putative intact prophages were present in the genomes of two of the five strains. Overall, vaginal Lactobacillus strains largely performed better in these in vitro assays than probiotic strains currently used in probiotics for vaginal health. Including the best-performing vaginal Lactobacillus isolates in a region-specific probiotic for vaginal health may result in improved BV treatment options.