The Interchain Disulfide Linkage of T-Cell Antigen Receptor-α and -β Chains Is a Prerequisite for T-Cell Activation

Complementary DNAs encoding the T-cell antigen receptor (TCR)-α and mutant TCR-β chains, lacking the interchain disulfide bond-related cysteine, were introduced into a TCR-α and -β protein-deficient T-cell line. TCR-α and the mutant TCR-β chains assembled with the CD3-ϵ, -γ, -δ, and -ζ subunits and were efficiently transported to the cell surface; however, the hybrid TCR molecules exhibited a diminished response to T-cell activation by major histocompatibility complex-bound antigen, superantigen, and TCR cross-linking. These results suggest that the interchain disulfide bond between the TCR clonotypic chains is not required for TCR assembly and cell surface expression, but it plays an important role in maintaining the functional integrity of the TCR complex.