Open AccessInduction of immune response to Streptococcus pneumoniae by administration of oral viridans streptococci via phosphorylcholine determinant
Author(s) -
Miwa Yoko,
Ito HiroO,
Inoue Masakazu,
Oho Takahiko
Publication year - 2005
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1016/j.femsim.2004.11.001
Subject(s) - phosphorylcholine , streptococcus pneumoniae , microbiology and biotechnology , biology , pneumococcal infections , antibody , immunogenicity , immune system , epitope , immunogen , isotype , immunology , pneumolysin , monoclonal antibody , antibiotics , biochemistry
Expression of the phosphorylcholine (PC) epitope was examined in 48 viridans streptococcal strains, including Streptococcus pneumoniae R36a as the positive control, and their immunogenicity to induce an S. pneumoniae ‐cross‐reactive response was evaluated in mice. Thirteen strains were found to express the PC epitope, while no obvious association was found between the taxonomic categories and PC expression. Serum antibody responses to S. pneumoniae cells were induced in mice by intraperitoneal injection of the PC‐positive, but not PC‐negative, strains. The cross‐reactive antibodies induced by non‐pneumococcal oral streptococci were readily inhibited by free hapten PC. IgM was the sole isotype of the anti‐pneumococcal and anti‐PC antibodies, and the phenomenon of immunological memory was not observed. Since the anti‐PC antibody is critically important for resistance against pneumococcal infection in mice, the present results indicate the possibility that PC‐expressing oral commensal bacteria have a significant influence on the hosts’ responsiveness to S. pneumoniae .