Figure 1. Six transduced cancer cell lines that express antigens at high levels were effectively killed in vitro.

(A) Diagram of fusion proteins constructed to express antigen in MC57 cancer cells. Triple repeats of peptide and AAY proteasomal cleavage sites were fused to fluorescent proteins: OVA₂₅₇, SIY, mouse tyrosinase_369–377 (Tyr₃₆₉), mouse or human gp100_25–33 (mgp100₂₅ and hgp100₂₅, respectively) and EGP; a Cerulean fusion gene was generated only for SIY. (B) Flow cytometric analysis of peptide-EGFP fusion proteins expressed by the transduced MC57 fibrosarcoma lines. (C) MC57-mgp100/SIY expressed mgp100₂₅ and SIY antigens as EGFP and Cerulean fusion proteins, respectively. The HLA-A2/D^b chimeric protein HHD was co-transduced with the Tyr₃₆₉-EGFP fusion protein to generate MC57-TyrHHD. Parental MC57 (gray) was analyzed for comparison. (D) Cytolysis of MC57 target cells overexpressing SIY, mgp100₂₅, hgp100₂₅, EGP, or Tyr₃₆₉ and HHD (Tyr) by 2C, pmel, AFH (Tyr-negative) or FH (Tyr-positive) T cells in a 4.5 h ⁵¹Cr-release assay. Cancer cells expressing non-cognate peptide were used as negative controls. These data are compiled of three experiments and are representative for seven independent experiments. See Figure S1 for induction of vitiligo by FH and pmel T cells.