CYP1B1-derived peptides are endogenously processed and presented by tumor cells. (A) Specific lysis of COS/A*0201 cells transfected with a construct encoding EGFP + CYP1B1 amino acids (aa) 170-213 by CYP190-specific CTLs (left panel, ♦) or aa 205-352 by CYP239-specific CTLs (right panel, ♦) but not control EGFP-transfected COS cells (⋄). (B) Lysis of primary follicular lymphoma cells by CYP190-specific and CYP239-specific CTLs (♦, HLA-A*0201–positive; ⋄, HLA-A*0201–negative FL cells). All graphs are representative of at least 2 independent experiments. Expression of CYP1B1 by tumor cells was confirmed by Western blotting.