A common idiotope on T cell receptors and antibodies expressed in the absence of network selection.

The monoclonal antibody F6(51), directed to an idiotope of MOPC 460-like anti-1,4,6-trinitrophenl (TNP) antibodies produced in IgHa mouse strains, identifies in helper T cells from C57BL/6 (IgHb) mice with (4-hydroxy-3-nitrophenyl)acetyl (NP)-self specificity, a clonotypic determinant functionally and biochemically associated with the specific T cell receptor. The expression of this antibody-related T cell clonotype in C57BL/6 mice, although "recurrent", is independent of network selection, as shown by its presence in B mice suppressed from birth with anti-mu antibodies, and in IgH-congenic mouse strains. These results indicate aleatory cross-reactivity between T cell receptors and antibodies and command caution in network interpretations for "idiotype sharing".