Flow diagram of the cell analysis.

<p>At day 1, some PBMC's were use directly for an <i>ex vivo</i> analysis of pp65 specific T cells. The remaining PBMC's were split in adherent and non-adherent cells. The non-adherent cells comprising the T cells were expanded on a pp65 peptide mixture. The peptide mixture was added overnight, washed away the next day, and the T cells were propagated on IL2 until day 7. At the same time, the adherent cells were cultured for 7 days in the presence of IL4 and GM-CSF to mature the into DC. At day 7, both the T cells and the DC's were harvested. The DC's were pulsed with the pp65 peptide mixture and added to the T cells (at the ratio 1∶10) during a 4 h ICS assay.