Adhesion of Gardnerella vaginalis to vaginal epithelial cells: variables affecting adhesion and inhibition by metronidazole.

Variables affecting the adherence of Gardnerella vaginalis to human vaginal epithelial cells were examined in vitro. Adherence depended on pH, with maximum attachment occurring between pH 5 and pH 6. Preincubation of the bacteria at 56 degrees C for 30 minutes and ultraviolet irradiation resulted in a noticeable decrease in adherence. In contrast, adherence was not altered by preincubating the epithelial cells under these conditions. Periodate oxidation of the vaginal cells caused an appreciable reduction in subsequent adherence of G vaginalis. None of the 19 single carbohydrates tested inhibited adherence completely. Metronidazole at subinhibitory concentrations for G vaginalis, appreciably reduced the adhesive capacity of G vaginalis, whereas subinhibitory concentrations of ampicillin did not.