Stimulatory activity of DCs pulsed with CEA peptide after treatment with various cytokines.

DCs, either untreated or treated with various cytokine combinations, were pulsed with CEA peptide (Cap-1) or Her2/neu peptide (each at 25 μg/mL) for 2 hours at 37°C in the presence 3 μg of β2-microglobulin. DCs were washed and were used as stimulators for autologous nonadherent PBMCs. Cells were cultured in the presence of IL-7 (10 ng/mL) and IL-2 (20 U/mL) for 12 days, followed by isolation of CD8⁺ T cells. The CD8⁺ T cells were restimulated with the corresponding DCs in the presence of IL-7 and IL-2. The CTL assay was performed 5 days after restimulation. T2 cells pulsed with CEA peptide or Her2/neu peptide were used as targets. Data are expressed as the mean percentage specific lysis of triplicate samples ± SD.