title: Identification, purification, and characterization of antigen-activated and antigen-specific human B lymphocytes.
abstract: Activated pneumococcal polysaccharide (PPS)-specific human B lymphocytes have been purified and examined in vitro. They are large cells that are refractory to further activation by antigen, anti-Ig, or Staphylococcus aureus Cowan strain I, but they respond directly by proliferation to B cell growth factors. In addition, they express the isotype pattern of activated cells and a surface marker of activated lymphocytes called 4F2. Finally, they contain a subset of cells that spontaneously secrete PPS-specific antibody.
mesh_terms: D000328:Adult; D000818:Animals; D000941:Antigens / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology; D001666:Binding Sites, Antibody; D002469:Cell Separation; D000939:Epitopes; D006133:Growth Substances / Q000502:physiology; D006801:Humans; D015847:Interleukin-4; D008213:Lymphocyte Activation; D051379:Mice; D022242:Pneumococcal Vaccines; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D012397:Rosette Formation
chemical_list: D000941:Antigens; D001428:Bacterial Vaccines; D000939:Epitopes; D006133:Growth Substances; D022242:Pneumococcal Vaccines; D011947:Receptors, Antigen, B-Cell; D015847:Interleukin-4