title: Role of accessory cells in B cell activation. IV. Ia+ accessory cells are required for the in vitro generation of thymic independent type 2 antibody responses to polysaccharide antigens.
abstract: It has been previously shown that the in vitro antibody response to TNP-Ficoll requires the presence of adherent accessory cells. In order to determine if this characteristic was unique to TNP-Ficoll or a general feature of the TI-2 antibody responses, responses to the polysaccharide antigens TNP-Levan and TNP-Dextran were studied. Also, it was determined if the functionally relevant accessory cell expresses Ia determinants. Passage of spleen cells over Sephadex G-10 abrogated the response to TNP-Levan and TNP-Dextran as well as to TNP-Ficoll. Addition of adherent accessory cells to the G-10 passed spleen cells reconstituted the response to all 3 antigens. Pretreatment of the adherent accessory cells with a specific anti-Ia serum plus complement abrogated the ability of these cells to provide accessory cell function in the responses to all 3 antigens. Thus, an Ia-positive adherent accessory cell is required for the generation of TI-2 antibody responses to these polysaccharide antigens. This raises the possibility that genetic restrictions may exist between the Ia-positive accessory cell and the lymphocytes involved in the responses to TNP-Ficoll, TNP-Dextran, and TNP-Levan.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D002003:Brucella abortus / Q000276:immunology; D002448:Cell Adhesion; D003911:Dextrans / Q000276:immunology; D005362:Ficoll / Q000276:immunology; D005630:Fructans / Q000276:immunology; D000949:Histocompatibility Antigens Class II; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011134:Polysaccharides / Q000276:immunology; D013154:Spleen / Q000166:cytology; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D003911:Dextrans; D005630:Fructans; D000949:Histocompatibility Antigens Class II; D011134:Polysaccharides; D014301:Trinitrobenzenes; D005362:Ficoll