Minimal CD8<sup>+</sup> T cell epitope within peptide 13 of MPT83.

<p>C57BL/6 mice (n = 3) were immunized with 100 µg DNA-MPT83 (▪) or pcDNA3 (□) control vector by i.m.i three times at two-weekly intervals. Four weeks post-immunization, the mice were harvested and the splenocytes were stimulated with nonameric peptides spanning the sequence of peptide 13 and overlapping by one residue (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034991#pone-0034991-t001" target="_blank">Table 1</a>) at 10 µg/ml, MPT83 (10 µg/ml) and ConA (3 µg/ml) and number of peptide-specific IFN-γ secreting T cells were measured by ELIspot after 16 h. Data shown are the means±SEM for triplicate samples from three mice and representative of two independent experiments. The statistical significance of differences was determined by the Student’s <i>t</i>-test (*, <i>p</i><0.05; ***, <i>p</i><0.001, ****, <i>p</i><0.0001).</p>