title: The presence of the putative Gardnerella vaginalis sialidase A gene in vaginal specimens is associated with bacterial vaginosis biofilm.
abstract: Bacterial vaginosis (BV) is a difficult-to-treat recurrent condition in which health-associated lactobacilli are outnumbered by other anaerobic bacteria, such as Gardnerella vaginalis. Certain genotypes of G. vaginalis can produce sialidase, while others cannot. Sialidase is known to facilitate the destruction of the protective mucus layer on the vaginal epithelium by hydrolysis of sialic acid on the glycans of mucous membranes. This process possibly facilitates adhesion of bacterial cells on the epithelium since it has been linked with the development of biofilm in other pathogenic conditions. Although it has not been demonstrated yet, it is probable that G. vaginalis benefits from this mechanism by attaching to the vaginal epithelium to initiate biofilm development. In this study, using vaginal specimens of 120 women enrolled in the Ring Plus study, we assessed the association between the putative G. vaginalis sialidase A gene by quantitative polymerase chain reaction (qPCR), the diagnosis of BV according to Nugent score, and the occurrence of a BV-associated biofilm dominated by G. vaginalis by fluorescence in situ hybridisation (FISH). We detected the putative sialidase A gene in 75% of the G. vaginalis-positive vaginal specimens and found a strong association (p<0.001) between the presence of a G. vaginalis biofilm, the diagnosis of BV according to Nugent and the detection of high loads of the G. vaginalis sialidase A gene in the vaginal specimens. These results could redefine diagnosis of BV, and in addition might guide research for new treatment.
authors.affiliation: HIV and Sexual Health Group, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.|Laboratory Bacteriology Research, Faculty of Medicine & Health Sciences, University of Ghent, Ghent, Belgium.|HIV/STI Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Liselotte
authors.identifier: http://orcid.org/0000-0002-8785-5081
authors.initials: L
authors.lastname: Hardy
authors.affiliation: HIV and Sexual Health Group, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Vicky
authors.initials: V
authors.lastname: Jespers
authors.affiliation: HIV/STI Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Magelien
authors.initials: M
authors.lastname: Van den Bulck
authors.affiliation: Clinical Trials Unit, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Jozefien
authors.initials: J
authors.lastname: Buyze
authors.affiliation: Rinda Ubuzima, Kigali, Rwanda.
authors.forename: Lambert
authors.initials: L
authors.lastname: Mwambarangwe
authors.affiliation: Rinda Ubuzima, Kigali, Rwanda.
authors.forename: Viateur
authors.initials: V
authors.lastname: Musengamana
authors.affiliation: Laboratory Bacteriology Research, Faculty of Medicine & Health Sciences, University of Ghent, Ghent, Belgium.
authors.forename: Mario
authors.initials: M
authors.lastname: Vaneechoutte
authors.affiliation: HIV/STI Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Tania
authors.initials: T
authors.lastname: Crucitti
mesh_terms: D000293:Adolescent; D000328:Adult; D018441:Biofilms; D005260:Female; D006194:Gardnerella vaginalis / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D006868:Hydrolysis; D017404:In Situ Hybridization, Fluorescence; D018613:Microscopy, Confocal; D009092:Mucous Membrane / Q000382:microbiology; D019158:N-Acetylneuraminic Acid / Q000737:chemistry; D009439:Neuraminidase / Q000235:genetics*; D020135:Peptide Nucleic Acids / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011134:Polysaccharides / Q000737:chemistry; D012432:Rwanda; D014621:Vagina / Q000382:microbiology*; D016585:Vaginosis, Bacterial / Q000201:enzymology*; D055815:Young Adult
chemical_list: D020135:Peptide Nucleic Acids; D011134:Polysaccharides; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid