title: Ontogeny of mouse B lymphocytes and inactivation by antigen of early B lymphocytes.
abstract: Taking advantage of recent findings about membrane fluidity, we have studied and compared the biosynthetic capacities of fetal or neonatal mouse B (bone-marrow derived) lymphocytes (until 10 days after birth) and adult B lymphocytes. Although both early and adult lymphocytes can synthesize surface immunoglobulins, they have a different physiological behavior after interaction with a ligand (anti-immunoglobulin sera or antigen), either in vivo or in vitro. Fetal and neonatal lymphocytes bearing surface immunoglobulins do not reexpress their membrane receptors after capping and endocytosis promoted by anti-immunoglobulin sera. On the other hand, adult lymphocytes resynthesize completely their receptors after the same treatment. Furthermore, intrafetal injections of hemocyanin in pregnant mice lead to a striking decrease in the number of hemocyanin-binding cells. It seems plausible that this non-reexpression of surface immunoglobulins could be the first step in tolerance establishment.
mesh_terms: D000367:Age Factors; D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation; D006433:Hemocyanins / Q000276:immunology / Q000378:metabolism; D007108:Immune Tolerance; D007075:Immunoglobulin M / Q000378:metabolism; D008099:Liver / Q000196:embryology; D051379:Mice; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D013154:Spleen / Q000196:embryology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell; D006433:Hemocyanins