title: Antigenicity and protective effects of type 3 pneumococcal polysaccharide in rats.
abstract: The response to type 3 pneumococcal polysaccharide vaccination, the protective effect of type 3 pneumococcal polysaccharide vaccination, and the ability of hemagglutinating antibody to type 3 pneumococcal polysaccharide to cross the blood-brain barrier were studied in rats. Hemagglutinating antibody response to vaccination with type 3 pneumococcal polysaccharide was found to be dependent on the dose and route of inoculation. Intraperitoneal vaccination with type 3 pneumococcal polysaccharide protected the rats from subsequent intraperitoneal challenge with type 3 Streptococcus pneumoniae but had no effect after intracisternal challenge with type 3 S. pneumoniae. In the presence or absence of sterile meningeal inflammation, hemagglutinating antibody could not be found in cerebrospinal fluid of animals vaccinated intraperitoneally with type 3 pneumococcal polysaccharide. These results suggest that type 3 pneumococcal polysaccharide is antigenic in rats and intraperitoneal vaccination with type 3 pneumococcal polysaccharide does not protect against experimental meningitis because antibodies do not cross the blood-brain barrier.
mesh_terms: D000373:Agglutinins / Q000096:biosynthesis*; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis* / Q000134:cerebrospinal fluid; D001812:Blood-Brain Barrier; D006388:Hemagglutinins / Q000096:biosynthesis* / Q000134:cerebrospinal fluid; D008297:Male; D011008:Pneumococcal Infections / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage / Q000276:immunology*; D051381:Rats; D013296:Streptococcus pneumoniae / Q000254:growth & development / Q000276:immunology*; D014611:Vaccination
chemical_list: D000373:Agglutinins; D000907:Antibodies, Bacterial; D006388:Hemagglutinins; D011135:Polysaccharides, Bacterial