<i>In vivo</i> cytotoxicity levels against the murine CMV CD8 T-cell epitope YPHFMPTNL detected in animals with pre-existing HAd5V immunity or control animals after immunization with different doses of HAd5V-based vaccine vector, HAd5VCMV.

<p>Mice were immunized by either i.n. or i.m. routes with different doses of HAd5VGFP as indicated (10³, 10⁵ or 10⁷ pfu/animal). Four weeks later, mice were vaccinated with one (prime) dose of 1×10⁹ pfu/animal of HAd5VCMV administered subcutaneously. The ^lowCFSE and ^highCFSE+^CMVCD8-peptide labeled cells were identified by flow cytometry using the gates shown in panel (A). Histograms show data from a single mouse. FS–forward scatter, SS–side scatter. (B) Percentage of specific lysis induced in vaccinated animals after a single immunization (prime). The specific lysis was normalized to the positive control (set as 100% of specific lysis). Negative control represents mice that were not immunized with any adenovirus vector. The graph in panel (B) shows one of three independent experiments with at least 3 mice per group. Bars represent mean values +/- SD. (+) ctrl–positive control, (-) ctrl–negative control; (-) mice non-immunized with adenovirus; i.n.–intranasal immunization route; i.m.–intramuscular immunization route.