Role of antigen and antibody in the regulation of the immune response.
The enzyme dextranase could degrade antigenic dextran in vivo even when given 6-15 d after the antigen. Dextranase injected after the antigen suppressed the immune response when given 24 but not 48 h after the antigen, indicating that the antigen must interact with the immune system for 48 h to initiate a response. Thereafter, the B cells are independent of further antigen stimulation. To show whether antibody-mediated suppression of the immune response was determinant specific FITC-conjugated SRC were applied as immunogen and antibodies were raised both against the carrier (SRC) and the FITC hapten. When these antibodies were injected 1-3 h after the immunogen they only suppressed the immune response to the corresponding determinant. Anti-carrier antibodies usually enhanced the response to the hapten. Therefore, antibody-mediated suppression of the immune response is determinant-specific and cannot be mediated in vivo to a detectable extent by the Fc part of the antibodies.
Möller
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D000818:Animals; D000906:Antibodies / Q000276:immunology*; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D003910:Dextranase; D003911:Dextrans / Q000276:immunology*; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins / Q000276:immunology; D007108:Immune Tolerance; D051379:Mice; D008815:Mice, Inbred Strains; D013861:Thiocyanates / Q000276:immunology; D013997:Time Factors
D000906:Antibodies; D000941:Antigens; D003911:Dextrans; D000939:Epitopes; D005452:Fluoresceins; D013861:Thiocyanates; D003910:Dextranase; D016650:Fluorescein-5-isothiocyanate