Identification of Ad-specific and EBV-specific T cells ex vivo using the ELISPOT assay of IFN-γ release. CD4-isolated and CD8-isolated T cells from 2 healthy seropositive donors, donor 4 and donor 5, were stimulated with autologous Ad5f35GFP-transduced DCs. T cells were used at different cell concentrations starting at 1 × 105 per well in the case of Ad-specific responses and 5 × 104 per well to detect EBV-specific responses. The assay was performed on triplicate samples, and the results shown, expressed as spot-forming cells (SFCs), are the averages of these triplicates, which had been corrected for background assessed using control wells containing T cells alone, APCs alone and, in the case of the Ad-specific response, nontransduced DCs plus T cells (mean, 142 SFCs per 105 cells for donor 4; and mean, 30.5 SFCs per 105 for donor 5). (A) The Ad-specific response detected ex vivo from donor 4. (B) The EBV-specific response detected from donor 4. (C-D) The Ad- and EBV-specific responses, respectively, detected from donor 5. Error bars indicate the standard error of 3 experiments.
