An invariant Vα24-JαQ/V/β11 T cell receptor is expressed in all individuals by clonally expanded CD4-8- T cells

Abstract

The T cell receptor (TCR)-α/β CD4-8- (double negative, DN) T cell subset is characterized by an oligoclonal repertoire and a restricted V gene usage. By immunizing mice with a DN T cell clone we generated two monoclonal antibodies (mAbs) against Vα24 and Vβ11, which have been reported to be preferentially expressed in DN T cells. Using these antibodies, we could investigate the expression and pairing of these Vα and Vβ gene products among different T cell subsets. Vα24 is rarely expressed among CD4+ and especially CD8+ T cells. In these cases it is rearranged to different Jα segments, carries N nucleotides, and pairs with different Vβ. Remarkably, Vα24 is frequently expressed among DN T cells and is always present as an invariant rearrangement with JαQ, without N region diversity. This invariant Vα24 chain is always paired to Vβ11. This unique Vα24-JαQ/Vβ11 TCR was found in expanded DN clones from all the individuals tested. These findings suggest that the frequent occurrence of cells carrying this invariant TCR is due to peripheral expansion of rare clones after recognition of a nonpolymorphic ligand.