P2X5 expression in KG1 AML cells results in recognition and lysis by LRH-1–specific CTLs. (A) P2X5 mRNA expression was determined by real-time quantitative RT-PCR in a panel of AML cell lines. (B) Specific cytotoxicity of LRH-1–specific CTL RP1 against AML cell lines KG1, KG1a, and K562 with and without transduction of HLA-B*0702. Specific lysis was determined after 2 days of coculture in a flow cytometry–based cytotoxicity assay at an E/T ratio of 0.5:1. (C) Survival up to 3 days of HLA-B*0702–transduced AML cell lines KG1 (▴), KG1a (▾), and K562 (♦) cocultured with LRH-1–specific CTL RP1 at an E/T ratio of 0.5:1. Data are displayed as mean plus or minus SD of triplicate wells.