Fig 3. In vivo cellular immunogenicity of MVA deletion mutants, lacking fifteen genes, with TIP antigen, in a prime-boost regimen.

Two groups of female BALB/c mice (n = 10) were immunized i.m. with 100μg of pSG-TIP DNA, then boosted with i.p. injection of MVAwt with TIP model antigen (MVA-TIP), or MVA deletion mutant (lacking 15 genes) ∆15-MVA-TIP at the dose of 1x10⁷ pfu/ml. 7 days (top), or 56 days (bottom) post-boost immunization, half of the mice were sacrificed and spleens collected for intracellular cytokine staining and flow cytometry to determine the percentage of IFN-γ-secreting CD8⁺ T splenocytes in response to in vitro re-stimulation with pb9 peptide (A), or with MVA vector-specific peptides (B and C). All values are presented after subtracting the values of unstimulated cells for every mouse (sample). The mean of each group with the SEM error bars are shown. Data is representative of two independent experiments. There was no statistical significant difference between the tested groups using Mann Whitney test.