Phenotype of patient treatment cells before and after infusion. DMF5 patient PBMCs were stained by tetramers for TCR-recognizing MART1:27-35, and by mAb for CD3 and the activation and differentiation markers CD27, CD28, CD45RA, and CD45RO. Cell phenotype was evaluated by flow cytometry, gated on CD3+ cells before treatment, and on CD3+tetramer+ cells for infusion (Rx) and 1 month after treatment (1 mo) samples. Error bars indicate mean ± SEM. Responding patients (PR) are represented by solid symbols, and nonresponding patients (NR) by open symbols.