CD8⁺ T-cell quality measured by its proliferative potential and its ability to recognized cross-reactive peptides.

<p>Specific cellular immune responses were analyzed at 10, 30 or 53 days after the immunization in groups of six BALB/c mice. Pooled splenocytes of DNA-EnvB/MVA-EnvB (grey bars) and DNA-EnvB+DNA-IL-12₅₀+CTB/MVA-EnvB+CTB (black bars) groups were evaluated. (A) CFSE-labeled cells were stimulated <i>in vitro</i> during 4 days with the specific V3 loop peptide and then stained with surface antibodies (CD3 and CD8). Proliferating CFSE low CD8 T-cells was determined by flow cytometry. A representative dot plot is depicted (left panel) and percentage of proliferating cells were analyzed (right panel). (B) Ten and 53 days after immunization, splenocytes were stimulated with different pools of Env PTE peptides and evaluated by ELISPOT. Bars represented the accumulated number of IFN-γ spot forming units (SFU)/10⁶ cells for the total PTE peptide-pools. (C) Magnitude of the response against the individual PTE peptide-pools is depicted. (B) and (C): Data are representative of two independent experiments. Bars represent the average +SD for duplicate samples. Background values were subtracted in each case. Statistical differences between groups: *p<0.05; **p<0.01; ***p<0.001 by Student's T test. (D) Scheme indicating the gp160 region included in the different PTE peptide pools.