title: Functional subsets of B cells defined by quantitative differences in surface I-A.
abstract: The quantitative expression of surface I-A determinants has been used to define functional B cell heterogeneity based on responsiveness to the trinitrophenyl (TNP) hapten on various classes of carrier molecules. Unprimed, anti-Thy 1 and complement-treated B10.A (I-Ak) B cells were stained with a monoclonal anti-I-Ak reagent that had been fluorescein (FL) conjugated. By using a fluorescence-activated cell sorter these cells were then sorted into 2 populations of cells staining heavily or lightly with this reagent. These populations of cells were then assayed for anti-TNP precursor frequency, in responses to 3 TNP-antigens, by limiting dilution analysis. B cells responsive to TNP-lipopolysaccharide (LPS) and TNP-sheep red blood cells (SRBC) were found in both the B cells that expressed a low amount of surface I-A and the B cells that expressed a high amount of I-A. However, B cells with the ability to respond to TNP-Ficoll were found only in the B cells that expressed a low amount of surface I-A. These experiments suggest that the quantitative expression of surface I-A can be used to define B cell populations with different abilities to respond to hapten coupled to Ficoll.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000276:immunology*; D001402:B-Lymphocytes / Q000145:classification* / Q000276:immunology; D003208:Concanavalin A / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D005452:Fluoresceins; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D011961:Receptors, Fc / Q000276:immunology; D012756:Sheep; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D000954:Antigens, Surface; D005452:Fluoresceins; D000949:Histocompatibility Antigens Class II; D008070:Lipopolysaccharides; D011961:Receptors, Fc; D014301:Trinitrobenzenes; D003208:Concanavalin A