Phosphorylcholine-specific helper T cells in mice with an X-linked defect of antibody production to the same hapten

F1 male mice with the CBA/N X-linked defect that are unable to produce plaque-forming cell responses to phosphorylcholine (PC) provide normal PC-specific helper T-cell activity when compared to F1 female littermates. Inhibition of helper activity with anti-idiotypic antiserum indicates that PC-specific T cells from both NBF1 female and male mice possess predominantly BALB/c myeloma protein HOPC-8 idiotypic determinants. Therefore, the CBA/N defect cannot be explained as a deletion of genes coding for V-region anti-PC specificities. The demonstration of helper activity in NBF1 male mice, which occurs in the absence of anti-PC antibody synthesis, also demonstrates the endogenous origin of the T-cell receptor.