Levels of gene-modified cells and transgene RNA expression decrease in PBL after adoptive cell transfer in patients with metastatic melanoma. (A) DNA was isolated from cells in the treatment infusion (day 1) and subsequent peripheral blood samples of patients receiving autologous MART-1–specific TCR-transduced lymphocytes. Real-time PCR was performed to quantify the amount of transgene DNA present at each time point. Each line represents a single patient, and data points represent the mean of 3 replicates ± SD. (B) Persistence of MART-1 TCR transgene, normalized to the infusion sample (INF) at various time intervals after infusion. (C) The kinetics of immune reconstitution in the peripheral blood after the nonmyeloablative, lymphodepleting chemotherapy regimen. Adoptive cell transfer, IL-2 administration, and peptide vaccinations were initiated on day 1. Data points represent the mean of all patients in this report ± SEM. ALC indicates absolute lymphocyte count; and ANC, absolute neutrophil count. (D) MART-1–specific TCR transgene RNA expression, corrected for the level of transgene DNA, at each time interval and normalized to the infusion value (INF).