Resistance to DEX and cytolytic activity of TALEN-modified CMV-specific CD8⁺ T cells. (A) Apoptosis of CMV-specific T cells (CMV^wt) and CMV-specific TALEN-modified T cells (CMV^GR-Ex2) measured by annexin V and propidium iodide staining after 72 hours in the presence of DEX (10⁻⁴ M). (B) Absolute number of live cells after 72 hours of DEX treatment measured by anti-CD8 staining and cell-counting beads. (C) Antigen-specific killing assay using CFSE-labeled target cells. The T2^GR-Ex2 cell line was pulsed with the pp65 (NLV) viral peptide for 1 hour and CFSE labeled prior to coculture with CMV-specific T cells under DEX for 72 hours. (D) Dose response of specific cytolytic activity under DEX. Data are represented as means ± standard deviation from 3 independent experiments; statistical analysis was performed by 1-way ANOVA (***P < .001). E:T, effector/target; NS, not significant.