title: Intrinsic tritium labeling of the capsular polysaccharide antigen of Haemophilus influenzae type B.
abstract: The capsular polysaccharide of Haemophilus influenzae type b was intrinsically labeled with tritium by a microculture technique with 6-3H-D-glucose and was isolated in radioantigenically pure form by a combination of selective precipitation and molecular sieve chromatography. Labeling with tritated sugar residues approached one-fourth maximum and produced a specific activity 10-fold that previously described for extrinsic labeling methods. In radioantigen-binding assays for antibody, sensitivity depended on the size of the antigen; preparations were readily made that could detect 0.01 microgram Ab/ml in serum samples of 25 microliter. Stability of the labeled antigen appears limited only by the primary radiodecomposition of tritium.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial; D001666:Binding Sites, Antibody; D002701:Chloramphenicol / Q000494:pharmacology; D002850:Chromatography, Gel; D000939:Epitopes; D006193:Haemophilus influenzae / Q000276:immunology*; D006801:Humans; D011135:Polysaccharides, Bacterial / Q000276:immunology / Q000378:metabolism*; D011817:Rabbits; D014316:Tritium
chemical_list: D000942:Antigens, Bacterial; D000939:Epitopes; D011135:Polysaccharides, Bacterial; D014316:Tritium; D002701:Chloramphenicol