Fig. 1.

The FluM1, Mart1 M26, and Cyp239 T-cell clones are peptide-specific and cytolytic. a Detection of FluM1, Mart1 M26, and Cyp239 T-cell clones by flow cytometry using antigen-specific tetramer (left, right) and pentamer (middle). b All three T-cell clones are cytolytic to peptide-pulsed HLA-A2+ CD40-B cells (5,000 target cells/well) at an E:T ratio of 10:1. Specific peptides were titrated in the concentrations shown. Background is unpulsed target cells. c The Mart1 M26 or Cyp239 T-cell clones were cocultured with tumor cell targets (5,000 target cells/well), and cytolytic activity was measured by standard europium release assay at the varying E:T ratios shown. The Mart1 T-cell clone efficiently lyses HLA-A2+ melanoma cells, including HLA-A2+ Mart1+ cells (melanoma cells K029 and C32TG), but not HLA A2− Mart1+ cells (K008), HLA-A2+ Mart1− cells (MCF-7), nor HLA-A2− Mart1− cells (SKBR-3). The positive control (T2 cells pulsed with Mart1 peptide M26) and negative control targets (T2 cells pulsed with FluM1 peptide) are shown