title: Development of B lymphocytes. I. Cell populations and a critical event during ontogeny.
abstract: The ontogeny of Ig(+), theta(+) and "null" (Ig-, theta-) lymphocytes in the mouse spleen was followed. An event was found at about 10 days after birth when the percentage of Ig(+) lymphocytes in the spleen begins to rise sharply, and the percentage of "null" lymphocytes falls. The Ig(+) lymphocytes before and after this event were then evaluated by four criteria pertaining to B cells. Three of these, the presence of C3 receptors, "capping" behavior, and the amount and/or disposition of surface Ig distinguished the Ig(+) lymphocytes before the event described from those present afterward. The fourth criterion, the presence of Fc receptors, did not distinguish between the early and mature forms of Ig(+) lymphocytes.
mesh_terms: D000375:Aging; D000818:Animals; D000961:Antilymphocyte Serum; D001345:Autoradiography; D001402:B-Lymphocytes / Q000276:immunology*; D001665:Binding Sites; D002462:Cell Membrane / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D005455:Fluorescent Antibody Technique; D007106:Immune Sera; D007141:Immunoglobulin Fc Fragments; D007457:Iodine Radioisotopes; D008214:Lymphocytes / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D011817:Rabbits / Q000276:immunology; D011947:Receptors, Antigen, B-Cell; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes
chemical_list: D000961:Antilymphocyte Serum; D007106:Immune Sera; D007141:Immunoglobulin Fc Fragments; D007457:Iodine Radioisotopes; D011947:Receptors, Antigen, B-Cell