title: Presence of plasma cells binding autologous antibody during an immune response.
abstract: Spleen and other lymphoid tissues of rabbits immunized with human serum albumin (HSA) and human lactoferrin (LF) were examined for the presence of cells forming anti-idiotype antibodies. To detect these cells, IgG, F(ab')2, or Fab' of specific antibodies were isolated, fluorochrome-tagged with tetramethylrhodamine isothiocyanate, and used as an idiotypic marker to detect splenic plasma cells that are producing anti-idiotypic antibody. By this procedure, we were able to demonstrate anti-idiotypic cells in surprisingly high numbers. For example, in six rabbits immunized with HSA for periods ranging from 36 to 542 d, the percentage of Ig-positive cells that stained with autologous idiotype ranged from 0.7 to 44; furthermore, cross-reactivity was observed among seven different anti-HSA preparations and two anti-LF antisera. The isotype of anti-idiotypic cells, determined by costaining with fluorescein isothiocyanate-labeled goat Fc-specific anti-rabbit Ig, was shown to be predominantly IgG. These findings provide evidence of the presence of plasma cells producing antibody to autologous idiotype during a vigorous immune response.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000939:Epitopes; D005260:Female; D005455:Fluorescent Antibody Technique; D007070:Immunoglobulin A / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007518:Isoantibodies / Q000096:biosynthesis*; D010950:Plasma Cells / Q000276:immunology*; D011817:Rabbits
chemical_list: D000939:Epitopes; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007518:Isoantibodies