title: Subpopulations of B lymphocytes in germinal centers.
abstract: With two new monoclonal antibodies and flow cytometry, we defined three subpopulations among B cells expressing binding sites for peanut agglutinin (i.e., B cells of the germinal center). On monoclonal antibody (5B5) binds globotriaosyl ceramide. The B lymphocytes binding 5B5 have binding sites for peanut agglutinin on the surface and express only small amounts of sIgD and sIgM. When tested against a panel of B cell lines, only Burkitt's lymphoma cells were 5B5+. Moreover, the 5B5+ cells have larger average sizes and a large fraction of proliferating cells. The other monoclonal antibody (HK23) binds a 90,000 protein. Lymphocytes binding HK23 are 5B5- and include T cells and a subpopulation of B cells. In contrast to 5B5+ cells, the HK23+ and peanut agglutinin positive B cells express a large amount of sIgM. These two subpopulations of germinal centers are distinct from the germinal center B cell subpopulation expressing the CD23 (Blast-2) antigen. The CD23+ B cells are 5B5- and express an intermediate level of HK23 antigen. In addition, CD23+ B cells are highly variable in number, whereas the proportions of HK23+ and 5B5+ cells are relatively stable.
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000276:immunology; D001402:B-Lymphocytes / Q000145:classification* / Q000276:immunology / Q000378:metabolism; D005915:Globosides / Q000276:immunology; D006801:Humans; D007072:Immunoglobulin D / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D037102:Lectins / Q000378:metabolism; D008198:Lymph Nodes / Q000166:cytology*; D008875:Middle Aged; D019887:Peanut Agglutinin; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D011975:Receptors, Mitogen / Q000276:immunology; D014281:Trihexosylceramides
chemical_list: D000911:Antibodies, Monoclonal; D005915:Globosides; D007072:Immunoglobulin D; D007075:Immunoglobulin M; D037102:Lectins; D019887:Peanut Agglutinin; D011947:Receptors, Antigen, B-Cell; D011975:Receptors, Mitogen; D014281:Trihexosylceramides; C038223:peanut agglutinin receptor; C018549:globotriaosylceramide