Antibodies against pneumococcal C-polysaccharide are not protective

Microb Pathog. 1993 Apr;14(4):299-305. doi: 10.1006/mpat.1993.1029.


The ability of antibodies against C-polysaccharide (C-Ps) to protect against experimental pneumococcal infection was examined in a mouse model. No protection against types 6A and 14 pneumococcal infection could be demonstrated neither with mouse monoclonal antibodies against C-Ps, specific for phosphorylcholine (PC) or for C-Ps backbone, nor for polyclonal rabbit immunsera against C-Ps. The monoclonal antibody with PC-specificity was protective against infection with type 27 pneumococcus, that has PC as part of its capsular polysaccharide. Type-specific mono- and polyclonal antibodies were highly protective against infection with the homologous type. We conclude that no species-specific protection can be achieved against intraperitoneal Streptococcus pneumoniae infection with optimally capsulated bacteria in outbred mice by passive immunization with antibodies to C-Ps.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Bacterial / immunology*
  • Antibodies, Monoclonal / immunology
  • Disease Models, Animal
  • Female
  • Mice
  • Pneumococcal Infections / immunology*
  • Polysaccharides, Bacterial / immunology*
  • Streptococcus pneumoniae / pathogenicity
  • Virulence


  • Antibodies, Bacterial
  • Antibodies, Monoclonal
  • Polysaccharides, Bacterial
  • polysaccharide C-substance (Streptococcus)