The role of surface IgD in the response to thymic-independent antigens.
An alloanti-delta antibody was prepared by immunizing C57BL/Ka mice with BALB/c spleen cells. Its specificity for delta-chain was demonstrated by immunoprecipitation and SDS-PAGE of 125I-labeled membrane proteins from BC8 spleen cells. BC8 mice possess C57BL/Ka "background" genes and BALB/c IgH genes. The anti-delta reagent without complement inhibited the primary in vitro anti-TNP antibody response to TNP-AECM-Ficoll by BC8 spleen cells, although it had no effect of the anti-TNP response of congenic C57BL/Ka spleen cells, which lack the delta-allotype identified by this antibody. On the other hand, the anti-delta antibody had no effect on the anti-TNP response of BC8 spleen cells to TNP-BA, except at limiting antigen concentrations. Both TNP-AECM-Ficoll and TNP-BA are T-I antigens, but they differ in that TNP-AECM-Ficoll fails to stimulate in vitro responses by immunologically defective CBA/N and neonatal spleen cells whereas TNP-BA can cause responses from both these animals. These results suggest that the IgD receptor is critical to T-I antibody responses initiated by TNP-AECM-Ficoll but that it is not required for T-I responses stimulated by TNP-BA.
D000818:Animals; D000917:Antibody Formation; D000941:Antigens; D001402:B-Lymphocytes / Q000276:immunology*; D000939:Epitopes; D007072:Immunoglobulin D / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D011947:Receptors, Antigen, B-Cell / Q000502:physiology*
D000941:Antigens; D000939:Epitopes; D007072:Immunoglobulin D; D011947:Receptors, Antigen, B-Cell