title: Phytohemagglutinin stimulation of enhanced immunoglobulin G production in mice inoculated with type III pneumococcal polysaccharide.
abstract: In BALB/c mice previously inoculated intraperitoneally with an immunogenic dose of the T-independent antigen type III pneumococcal polysaccharide, the intravenous administration of the T-cell activating agent phytohemagglutinin P causes a pronounced increase in the number and relative proportion of immunoglobulin G-producing cells. These results, detected by a modified hemolytic plaque assay, were supported by finding increased levels of serum immunoglobulin G anti-type III pneumococcal polysaccharide in the treated mice. A comparable stimulation of immunoglobulin G antibody-producing cells was not induced in phytohemagglutinin P-treated nude mice, indicating that the change in class of the predominant antibody is attributable to the activation by the phytohemagglutinin P of a T-cell population. Under the conditions of these experiments, phytohemagglutinin P also promotes a progressive suppression of the antibody-forming cells during the response to type III pneumococcal polysaccharide.
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D000921:Antibody-Producing Cells / Q000276:immunology; D005260:Female; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007075:Immunoglobulin M / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D010835:Phytohemagglutinins / Q000494:pharmacology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D010835:Phytohemagglutinins; D011135:Polysaccharides, Bacterial