Changes of the CE response in macaques vaccinated with p55^gag DNA after heterologous boost with p24CE DNA and upon co-immunization with p24CE and p55^gag DNA.

<p>(<b>A</b>) Vaccination schedule of the animals primed with p55^gag DNA and boosted with p24CE DNA. (<b>B</b>) Four of the p55^gag DNA vaccinated animals, which developed cellular immune responses targeting CE (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0086254#pone-0086254-t001" target="_blank"><b>Table 1</b></a>), received an additional vaccination with p24CE DNA. PBMC isolated 2 weeks after the 2^nd p55^gag DNA vaccination (vaccination 2) and after the p24CE DNA boost (vaccination 3) were stimulated with a CE-specific peptide pool (15- and 10-mer) covering individual 7 CE to map CE-specific T cell responses. The percentage of IFN-γ⁺ CD4⁺ (open bars) and CD8⁺ (filled bars) T cells specific for each CE is shown. (<b>C</b>) Frequencies of the total CE-specific IFN-γ⁺ T cells and (<b>D</b>) of the polyfunctional (4 functions; IFN-γ⁺ TNF-α⁺ CD107a⁺ GzmB⁺) CE-specific T cells are shown before and after the heterologous boost. (<b>E</b>) Vaccination schedule of the animals co-immunized with p24CE and p55^gag DNA. (<b>F</b>) PBMC isolated 2 weeks after the vaccinations 2 and 3 were stimulated with a CE-specific peptide pool covering the 7 individual CE. The percentage of IFN-γ⁺ CD4⁺ (open bars) and CD8⁺ (filled bars) T cells specific for each CE is shown. The frequencies of the total (<b>G</b>) CE-specific IFN-γ⁺ T cells and of the (<b>H</b>) polyfunctional (4 functions) CE-specific T cells are shown.