Haemagglutination by vaginal anaerobic curved rods and its inhibition by oligosaccharides

Except for occasional (6/45) strains, both the short (21/24) and long (16/21) variants of anaerobic curved rods isolated from the vagina of women with bacterial vaginosis were capable of agglutinating human, guinea pig and sheep erythrocytes. The agglutination was not affected by heat treatment, i.e. up to 80 degrees C for 30 minutes, of the bacteria prior to use. Nor was the agglutination influenced by 50 mM EDTA or 50 mM D-mannose. To elucidate receptors on the erythrocyte membrane responsible for the agglutination, various free oligosaccharides and glycoproteins were tested for haemagglutination-inhibiting capacity, using representative strains of the short variant. Glycoproteins containing terminal lactosamine structures inhibited the agglutination.