title: Membrane immunoglobulins of B lymphocytes: inability to detect certain characteristic IgM and IgD antigens.
abstract: Hemagglutination and fluorescent antibody studies have provided strong evidence for the unavailability or absence of specific antigenic sites on membrane-bound IgM which are present in serum and intracellular IgM. Antisera specific for different parts of the molecule indicated that a portion but not all of the Fc was involved. Absorption experiments with normal and leukemic viable B lymphocytes failed to remove a population of Fc antibodies found in IgM-specific antisera. Similar findings were made for IgD, the other major membrane immunoglobulin of human peripheral blood B cells. Various interpretations of these observations are discussed. The most likely possibility appears that the C-terminal portion of the heavy chains of the immunoglobulin molecule is buried in the membrane.
mesh_terms: D000888:Antibodies, Anti-Idiotypic; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D001402:B-Lymphocytes / Q000276:immunology*; D001666:Binding Sites, Antibody; D002462:Cell Membrane / Q000276:immunology; D000939:Epitopes; D004912:Erythrocytes / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006384:Hemagglutination; D006801:Humans; D007072:Immunoglobulin D / Q000032:analysis*; D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007075:Immunoglobulin M / Q000032:analysis*; D007945:Leukemia, Lymphoid / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000939:Epitopes; D007072:Immunoglobulin D; D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007075:Immunoglobulin M