Fig. 4.

TCR α- and β-chain pairing and mispairing. A genetically modified TCR T cell expresses both the endogenous and transduced α/β TCR chains. There are four possible TCR chain combinations: (1) an endogenous α and β chain TCR; (2) a TCR generated from the transduced exogenous α and β TCR sequences; and (3 and 4) hybrid (mispaired) TCRs formed from a combination of endogenous and exogenous α and β chains. The reactivity of the hybrid TCRs is unknown and is a potential source of self-reactive toxicities.