Down-regulation of transgene expression is similar to that of endogenous genes. (A) β-actin RNA expression, corrected for the level of β-actin DNA, before (PRE) and at time intervals after cell infusion were normalized to the infusion value (INF). Corrected RNA expression of the endogenous TCR α-chain (B) and CD3ϵ (C) before (PRE) and at time intervals after cell infusion were normalized to the infusion values (INF). (D) The relative, corrected MART-1–specific TCR transgene expression and the relative, corrective expression of β-actin, the endogenous TCR α-chain, and CD3ϵ at each time interval after treatment. Values are the mean of the analyzed patients ± SEM.