title: Distribution of kappa and lambda light chain isotypes among human blood immunoglobulin-secreting cells after vaccination with pneumococcal polysaccharides.
abstract: The light chain isotype of immunoglobulin-secreting blood cells was investigated by means of monolayer plaque-forming cell assays allowing direct immunofluorescence staining for cytoplasmic kappa and lambda light chains in centre cells. The study revealed that cultured, polyclonally activated pokeweed mitogen (PWM) and Epstein-Barr virus (EBV), IgM-, IgG- and IgA-secreting cells expressed the kappa light chain isotype in approximately 65% of the cells. IgM- and IgG-secreting cells induced by vaccination with pneumococcal polysaccharides had a similar percentage of kappa light chain-containing cells. In contrast, IgA-secreting cells induced by vaccination with pneumococcal polysaccharides showed a different (bimodal) distribution as regards expression of kappa light chain. The majority (56%) of the investigated individuals expressed kappa light chain in approximately 50% of the cells and the rest expressed kappa light chains in approximately 80% of the cells. The percentage of cells containing kappa light chains among spontaneous IgA-secreting cells in unvaccinated individuals was approximately 50% and thus also differed from the general pattern for mitogen-activated B cells. The light chain pattern of IgA-secreting cells from individuals vaccinated with pneumococcal polysaccharides and from unvaccinated individuals probably indicates that these cells are being derived from B-cell clones with a limited idiotypic heterogeneity, which have been selected and clonally expanded by naturally occurring antigens at the mucosal membranes.
authors.affiliation: Department of Paediatrics G, University Hospital, Copenhagen, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Heilmann
authors.forename: T
authors.initials: T
authors.lastname: Barington
mesh_terms: D000328:Adult; D000921:Antibody-Producing Cells / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D006462:Hemolytic Plaque Technique; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000032:analysis; D007132:Immunoglobulin Isotypes / Q000032:analysis*; D007145:Immunoglobulin kappa-Chains / Q000032:analysis*; D007146:Immunoglobulin lambda-Chains / Q000032:analysis*; D022242:Pneumococcal Vaccines; D013296:Streptococcus pneumoniae / Q000276:immunology*; D014611:Vaccination
chemical_list: D001428:Bacterial Vaccines; D007071:Immunoglobulin A, Secretory; D007132:Immunoglobulin Isotypes; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D022242:Pneumococcal Vaccines