Differential expression of γ-chain cytokine receptors during T-cell gene transfer. Kinetics of CD25 (A) and CD127 (B) expression on transduced cells is shown. Briefly, PBMCs were stimulated with either baCD3/CD28⁺ IL-7/IL-15 (◆), baCD3/CD28⁺ IL-7 (), baCD3/CD28⁺ IL-2 (), or aCD3⁺ IL-2 (□). At 48 and 72 hours after stimulation, cells were transduced with the RV SFCMM-3 Mut2. At day 7, transgene-positive cells were selected magnetically and cultured for additional 6 days with corresponding cytokines. Expression of IL-2Rα (CD25) and IL-7Rα (CD127) were measured by flow cytometry at days 2, 4, 9, and 13. Six hours before staining with anti-CD25 and anti-CD127 antibodies, cytokines were removed. Averages plus or minus SD of 6 independent experiments from different donors are shown. *P < .05; **P < .01. Asterisks only on aCD3⁺ IL-2 indicate significant differences versus all other samples.