Investigating the candidacy of the serotype specific rhamnan polysaccharide based glycoconjugates to prevent disease caused by the dental pathogen Streptococcus mutans

AbstractDental caries remains a major health issue and the Gram-positive bacteriumStreptococcus mutans is considered as the major pathogen causing caries. More recently,S. mutans has been recognised as a cause of endocarditis, ulcerative colitis and fatty acid liver disease along with the likelihood of increased cerebral hemorrhage following a stroke ifS. mutans is present systemically. We initiated this study to examine the vaccine candidacy of the serotype specific polysaccharides elaborated byS. mutans. We have confirmed the carbohydrate structures for the serotype specific rhamnan containing polysaccharides from serotypes c, f and k. We have prepared glycoconjugate vaccines using the rhamnan containing polymers from serotypes f and k and immunised mice and rabbits. We consistently obtained a robust immune response to the glycoconjugates with cross-reactivity consistent with the structural similarities of the polymers from the different serotypes. We developed an opsonophagocytic assay which illustrated the ability of the post-immune sera to facilitate opsonophagocytic killing of the homologous and heterologous serotypes at titers consistent with the structural homologies. We conclude that glycoconjugates of the rhamnan polymers ofS. mutans are a potential vaccine candidate to target dental caries and other sequelae following the escape ofS. mutans from the oral cavity.

Source: Glycoconjugate Journal - October 2, 2017 Category: Biochemistry Source Type: research