title: Mechanism of effector cell blockade--IV. Induction by monoclonal anti-mu or anti-idiotypic antibody, role of secreted IgM and mechanism of decreased secretion.
abstract: Effector cell blockade (ECB), the inhibition of antibody synthesis by antigen or antigen-antibody complexes, was shown to be induced by monoclonal anti-mu or anti-idiotypic antibodies. An initial event in the induction of blockade was demonstrated to be the build up on the cell surface of a complex of membrane Ig, and either antigen or anti-mu or anti-Id antibody, together with secreted IgM. Trapping of secreted IgM in this complex was not, however, sufficient to account for the overall reduction in antibody secretion. This reduction was not due to reduced translation of mu mRNA, but rather to blockade of the normal process of assembly of the IgM molecule which was followed by increased intracellular degradation of intermediate precursor molecules. These findings have shown ECB to be a rapidly induced negative feedback control of IgM secretion which, at least initially, could be reversed. ECB may act in vivo as a flexible first-line mechanism for prevention of overproduction of IgM antibodies.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000917:Antibody Formation; D000936:Antigen-Antibody Complex; D000954:Antigens, Surface / Q000276:immunology; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D006825:Hybridomas / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology*; D007148:Immunoglobulin mu-Chains / Q000276:immunology; D011817:Rabbits; D051381:Rats
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D000954:Antigens, Surface; D000939:Epitopes; D007130:Immunoglobulin Idiotypes; D007075:Immunoglobulin M; D007148:Immunoglobulin mu-Chains