IDENTIFICATION OF 2 DISTINCT FUNCTION GAMMA-DELTA-TCR COMPLEXES ON THE SURFACE OF A HUMAN T-CELL CLONE

In this study we describe the expression of two T cell receptor (TCR) gamma chains on the surface of a human T cell clone isolated from the peripheral blood. Each gamma chain was part of an independent and func tional TCR. The dual receptor T cell clone (and all subclones derived from this clone) had stable expression of this phenotype. Immunoprecip itation studies revealed the expression of non-disulfide linked TCRs b y this V gamma 4(+)V gamma 9(+)V delta 1(+) T cell clone, which was in agreement with the finding that both V gamma gene transcripts were re arranged to C gamma 2-associated joining elements. Both gamma chains w ere derived from productive rearrangements of different (allelic) gene s coding for a V gamma 4(+) and a V gamma 9(+) gamma-chain, and both w ere coupled to a V delta 1(+) delta chain. Incubation of this V gamma 4(+)V gamma 9(+)V delta 1(+) T cell clone with TCR gamma-chain-specifi c MoAbs rapidly induced an increase in intracellular Ca++, indicating that both gamma-chains are functional. Furthermore, this clone respond ed to stimulation with S. aureus derived superantigens. We suggest the refore that exogenous (super)antigens can trigger dual receptor T cell s resulting in activation of these T cells.