| Abstract: | An adoptive cell transfer system was utilized to evaluate the site of action of the suppressive mechanism involved in antigenic competition in IgE antibody production. Carrier-primed (OA) and hapten-primed (DNP-KLH) spleen cells were transferred to syngeneic irradiated recipients that were challenged with a heterologous conjugate (DNP-OA). To study the effect of antigenic competition on T and B cells, donor mice of one or the other cell type received in addition the competitor antigen (Asc) at immunization. The adoptive secondary IgE anti-DNP antibody response was suppressed in both situations. This effect could not be attributed to transfer of Asc-primed cells. Irradiation of donor mice before immunization with the two antigens abrogated the suppressive effect. These results indicate that both Th and B cells primed to the test antigen were affected by antigenic competition. |
