Tetramer staining of T cells after stimulation with cDCs. Tetramer staining of T cells from patient no. 1 after 1 cycle (day 8) and 2 cycles (day 16) of stimulation with cDCs. CD8-enriched T cells were stimulated with cDCs pulsed with Hu157, the CMV pp65-derived peptide NLV, or no antigen (No Ag) as indicated in boldface. This indication applies to both rows of panels. Then, the stimulated T cells were stained with HLA-A*0201 tetramers loaded with Hu157, NLV, or irrelevant peptide as indicated by the x-axis labels of each panel. The percentage of CD8+ NLV-tetramer-positive T cells (upper right quadrants) increased from 0.01% of the T cells (No Ag, day 8) to 25% of the T cells (NLV, day 16). The percentage of Hu157-tetramer-positive T cells remained similar to that of the negative control tetramer (Irrelevant A2). Abbreviations: Hu157, cDCs pulsed with Hu157 peptide; NLV, cDCs pulsed with the CMV pp65-derived peptide NLV; Hu157 A2, HLA-A*0201 tetramer loaded with Hu157; NLV A2, HLA-A*0201 tetramer loaded with NLV; Irrelevant A2, tetramer loaded with irrelevant peptide.