title: In vivo polyclonal stimulation of antibody secretion by two types of bacteria.
abstract: We previously proposed that one benefit of early polyclonal antibody secretion after bacterial infection might be the formation of antibodies protective against infection by a second pathogen. In order to analyse this possibility, the polyclonal and anti-phosphorylcholine (PC) plaque-forming cell (PFC) response induced by Staphylococcus aureus Cowan I (SA) was compared with the same responses stimulated by unencapsulated Streptococcus pneumonia strain R36a. S. aureus stimulated significant anti-PC PFCs, despite an inability to detect immunoassay-reactive PC on the surface of SA (present on R36a). The induction of these antibodies appeared very similar to the mechanism for producing polyclonal responses. R36a also stimulated both anti-PC and polyclonal PFCs, but by different means. In summary, our data suggest that each type of bacteria induces polyclonal and anti-PC responses through different mechanisms, and that the polyclonal antibody response stimulated by one group of bacteria can contain antibodies directed towards a second and different genus of bacteria.
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D000918:Antibody Specificity; D000921:Antibody-Producing Cells / Q000276:immunology; D006462:Hemolytic Plaque Technique; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D010447:Peptide Hydrolases / Q000494:pharmacology; D010767:Phosphorylcholine / Q000276:immunology; D013211:Staphylococcus aureus / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D010767:Phosphorylcholine; D010447:Peptide Hydrolases