title: In vitro tolerance induction of neonatal murine B cells.
abstract: The susceptibility of neonatal and adult B lymphocytes to tolerance induction was analyzed by a modification of the in vitro splenic focus technique. This technique permits stimulation of individual hapten-specific clonal precursor cells from both neonatal and adult donors. Neonatal or adult BALB/c spleen cells were adoptively transferred into irradiated, syngeneic, adult recipients which had been carrier-primed to hemocyanin (Hy), thus maximizing stimulation to the hapten 2,4-dinitrophenyl coupled by Hy (DNP-Hy). Cultures were initially treated with DNP on several heterologous (non-Hy) carriers and subsequently stimulated with DNP-Hy. Whereas the responsiveness of adult B cells was not diminished by pretreatment with any DNP conjugate, the majority of the neonatal B-cell response was abolished by in vitro culture with all of the DNP-protein conjugates. During the 1st wk of life, the ability to tolerize neonatal splenic B cells progressively decreased. Thus, tolerance in this system is: (a) restricted to B cells early in development; (b) established by both tolerogens and immunogens; (c) achieved at low (10(-9) M determinant) antigen concentrations; and (d) highly specific, discriminating between DNP- and TNP-specific B cells. We conclude that: (a) B lymphocytes, during their development, mature through a stage in which they are extremely susceptible to tolerogenesis; (b) the specific interaction of B-cell antigen receptors with multivalent antigens, while irrelevant to mature B cells, is tolerogenic to neonatal (immature) B cells unless antigen is concomitantly recognized by primed T cells; and (c) differences in the susceptibility of immature and mature B lymphocytes to tolerance induction suggest intrinsic differences between neonatal and adult B cells and may provide a physiologically relevant model for the study of tolerance to self-antigens.
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn / Q000276:immunology; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology; D000939:Epitopes; D006241:Haptens; D007108:Immune Tolerance; D051379:Mice; D008807:Mice, Inbred BALB C; D009578:Nitrobenzenes / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors
chemical_list: D002352:Carrier Proteins; D000939:Epitopes; D006241:Haptens; D009578:Nitrobenzenes