Antigen-specific activation of hTERT-transduced CD4⁺T cells. Top graph shows the production of IFNγ by hTERT-GFP–transduced (□) and untransduced CD4⁺ T-cell clone MoT-81 (▪), stimulated for 24 hours with tetanus toxoid peptide 16-35 or control tetanus toxoid peptide 941-960 (○ and •, respectively) at the indicated concentrations. Bottom graph shows the stimulation of hTERT-GFP transduced (□) and untransduced CD4⁺ T-cell clone MoT-98 (▪) with tetanus toxoid peptide 16-35 or control tetanus toxoid peptide 941-960 (○ and •, respectively). ELISA assays were performed on supernatants of triplicate cultures. Graphs show a representative example of 2 experiments.