The occurrence of defined idiotypes on autoantibodies to mouse thyroglobulin

Anti‐idiotypic antibodies were raised in rabbits to three monoclonal mouse autoantithyroglobulins. Of the idiotypes recognized, one was unique to that monoclonal, while the other two showed evidence of sharing idiotopes with other monoclonal anti‐thyroglobulin (TG) idiotypes, the IgM idiotype in particular being found on nearly half of the hybridomas studied. Two of the idiotypes could be detected in the sera of mice with experimental allergic thyroiditis (EAT), but they constituted only a very small percentage of the total anti‐TG present. In spite of its low levels in EAT mice the D8 idiotype could be induced by injection of anti‐idiotype and TG and in this case it constituted up to 20% of the anti‐TG activity in individual mice, showing a strain‐related association between the idiotype and autoanti‐TG.