Preferential association of alpha and beta chains of the T cell antigen receptor.

The cytotoxic T lymphocyte (CTL) clone B6.2.16 expresses a V beta 8.2/J beta 2.3/C beta 2-encoded T cell receptor (TcR) beta chain and an alpha chain that is encoded by a novel V alpha gene segment, J alpha 27 and C alpha. While expression of V alpha B6.2.16 and J alpha 27 is not detectable in lymph node cells of normal C57BL/6 mice, expression of these gene segments was readily seen in transgenic mice expressing the rearranged beta chain gene of the B6.2.16 T cell clone. This finding indicates that only a limited number of alpha chains can associate with the B6.2.16 beta chain and strongly suggests that the size of the TcR repertoire of mature T cells is not only limited by TcR ligand-mediated thymic selection but also by restrictions in alpha-beta combinatorial chain association.