CD6+ CTL activity generated following second boost. PBMCs from Ad5-FMDV-B (p864, p865, and p866)- or Ad5-FMDV-T (p925, p945 and p947)-vaccinated pigs were isolated before and following boosting and treated as described in the legend to Fig. 5, except that only data from Ad5-FMDV-T secondary antigen stimulation are shown. Target cells: ⧫, Ad5-FMDV-T; ▪, mock. Additionally, pigs 864, 865, and 866 were tested on target cells: ▴, Ad5-FMDV-B; •, Ad5-VSV-G. Data from all time points are shown relative to Ad5-Empty. Error bars represent the standard deviation of results for duplicate wells.