Parallel expression of new idiotypes on T and B cells.

Abstract

THE structural nature of the antigen receptor on thymus-derived (T) cells is as yet unresolved1–4. It has been clearly demonstrated that antigen receptors on bone marrow-derived (B) cells are immunoglobulin (Ig) molecules which are similar to the antibodies secreted by their progeny5–7. This is further reflected in the presence of common variable region determinants present on Ig receptors and on antibodies produced by B cells belonging to the same clone8,9. These variable region determinants are called idiotypes10. We report here the use of anti-idiotypic antibodies to determine whether receptors on T and B cells specific for the hapten phosphorylcholine (PC) share idiotypic determinants. The majority of PC-specific B cells in BALB/c mice have receptors bearing an idiotype characteristic of the myeloma protein TEPC 15 (T15) (ref. 8). To determine whether receptors on PC-specific T cells also reflect this ‘idiotypic homogeneity’, we have induced PC-specific helper T cells and attempted to inhibit their activity using anti-T15 antibodies. Our results indicate that receptors on PC-specific T and B cells share similar idiotypes.