Antigen-specific memory and virgin B cells differ in their requirements for conjugation to T cells.
The physical interaction between carrier-specific T hybridoma cells and long-term primed, TNP-specific memory B cells (TNP-MABC) exposed to TNP-OVA was compared to that of unprimed, TNP-specific virgin B cells (TNP-ABC). The direct conjugation of the T and B cells was visualized at the light microscopic level and the number of T/B conjugates was quantified directly. The results demonstrate that the TNP-MABC, as compared to TNP-ABC, formed T/B conjugates after a shorter exposure time to antigen and at a 10-fold lower concentration of antigen. Conjugate formation was inhibited almost completely by treating the TNP-MABC with concentrations of chloroquine that only partially inhibited the ability of the TNP-ABC to form conjugates. Exposure of the T hybridoma cells or the TNP-ABC to monoclonal antibodies directed against cell surface antigens prior to conjugation indicated that L3T4, Thy-1.2, and LFA-1 antigens on the T cells and LFA-1 and I-A antigens on the TNP-ABC are involved in conjugate formation. However, in contrast to the TNP-ABC where treatment of the B cells with anti-LFA-1 blocked T/B conjugate formation, pretreatment of the TNP-MABC with anti-LFA-1 had no effect.
D000818:Animals; D000911:Antibodies, Monoclonal; D000921:Antibody-Producing Cells / Q000276:immunology*; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002738:Chloroquine / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D006825:Hybridomas / Q000276:immunology; D007156:Immunologic Memory; D008211:Lymphocyte Cooperation / Q000187:drug effects; D051379:Mice; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D013997:Time Factors; D014302:Trinitrobenzenesulfonic Acid / Q000276:immunology
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D002738:Chloroquine; D014302:Trinitrobenzenesulfonic Acid