title: Interactions between Lactobacillus crispatus and bacterial vaginosis (BV)-associated bacterial species in initial attachment and biofilm formation.
abstract: Certain anaerobic bacterial species tend to predominate the vaginal flora during bacterial vaginosis (BV), with Gardnerella vaginalis being the most common. However, the exact role of G. vaginalis in BV has not yet been determined. The main goal of this study was to test the hypothesis that G. vaginalis is an early colonizer, paving the way for intermediate (e.g., Fusobacterium nucleatum) and late colonizers (e.g., Prevotella bivia). Theoretically, in order to function as an early colonizer, species would need to be able to adhere to vaginal epithelium, even in the presence of vaginal lactobacilli. Therefore, we quantified adherence of G. vaginalis and other BV-associated bacteria to an inert surface pre-coated with Lactobacillus crispatus using a new Peptide Nucleic Acid (PNA) Fluorescence In Situ Hybridization (FISH) methodology. We found that G. vaginalis had the greatest capacity to adhere in the presence of L. crispatus. Theoretically, an early colonizer would contribute to the adherence and/or growth of additional species, so we next quantified the effect of G. vaginalis biofilms on the adherence and growth of other BV-associated species by quantitative Polymerase Chain Reaction (qPCR) technique. Interestingly, G. vaginalis derived a growth benefit from the addition of a second species, regardless of the species. Conversely, G. vaginalis biofilms enhanced the growth of P. bivia, and to a minor extent of F. nucleatum. These results contribute to our understanding of BV biofilm formation and the progression of the disorder.
authors.affiliation: Centre of Biological Engineering, IBB-Institute for Biotechnology and Bioengineering, University of Minho, Campus de Gualtar 4710-057, Braga, Portugal. nunocerca@ceb.uminho.pt.
authors.forename: António
authors.initials: A
authors.lastname: Machado
authors.forename: Kimberly Kay
authors.initials: KK
authors.lastname: Jefferson
authors.forename: Nuno
authors.initials: N
authors.lastname: Cerca
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001422:Bacterial Adhesion; D018441:Biofilms / Q000254:growth & development*; D005260:Female; D006801:Humans; D007778:Lactobacillus / Q000502:physiology*; D056265:Microbial Interactions / Q000502:physiology*; D016133:Polymerase Chain Reaction; D013045:Species Specificity; D013499:Surface Properties; D016585:Vaginosis, Bacterial / Q000382:microbiology*