MDM-2_53-61 is immunogenic in HLA-A2+ normal donors but not in patients with HNC. DCs were prepared from the peripheral blood of 5 normal donors (panel A) and 4 patients with HNC (panel B) as outlined in Materials and Methods, pulsed with the MDM-2_53-61 peptide for 2 h at 37°C, prior to washing and addition to autologous responder T cells at a T:dendritic cell ratio of 50:1. A second identical DC/peptide restimulation was provided one week later and CD8+ T cells were analyzed for specific reactivity one week after this secondary boost in IFN-gamma ELISPOT assays against T2 control cells or T2 cells pulsed with the indicated peptides. HIV-nef peptide was included as a negative control. All determinations were performed in triplicate, with results reported as the mean ± SD.