title: Expression of cell surface markers after human B lymphocyte activation.
abstract: The fate of two recently described human B lymphocyte-specific antigens (B1 and B2) was studied after B-cell activation in vivo and in vitro. Whereas both B1 and B2 were present on virtually all B cells from normal lymph nodes, B2 was absent from approximately 50% of B cells from hyperplastic lymph nodes. When B cells from spleen, tonsil, or peripheral blood were stimulated in vitro with pokeweed mitogen, activated cells were found to lose B2 (days 4-5) and subsequently B1 (days 6-7). Temporally, B2 loss was accompanied by loss of surface IgD, expression of T10, and the development of intracytoplasmic IgM; B1 loss was correlated with the acquisition of surface IgG and the appearance of intracytoplasmic IgG. Peripheral blood B cells, on which B2 is normally only weakly expressed (B1++++B2+) in contrast to B cells from secondary lymphoid organs (B1++++B2++), exhibited a transitory increase in B2 expression to the B1++++B2++ phenotype prior to B2 disappearance during activation. Taken together with other findings, this observation suggests that peripheral blood may contain a relatively immature subpopulation of B cells.
mesh_terms: D000921:Antibody-Producing Cells / Q000276:immunology*; D000954:Antigens, Surface; D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation / Q000187:drug effects; D003593:Cytoplasm / Q000276:immunology; D006801:Humans; D007136:Immunoglobulins / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects; D008221:Lymphoid Tissue / Q000276:immunology; D010641:Phenotype; D011043:Pokeweed Mitogens / Q000494:pharmacology; D014018:Tissue Distribution
chemical_list: D000954:Antigens, Surface; D007136:Immunoglobulins; D011043:Pokeweed Mitogens