Expression of CD20 on normal B cells severely inhibits the in vivo antileukemic function of CD20-specific cTCR⁺ T cells. (A) WT or hCD20 mice were injected intravenously with 2 × 10⁷ BM185-hCD20/Thy1.1-ffLuc-Neo leukemia cells and treated with 10⁷ Leu16 cTCR or empty vector–transduced Thy1.1⁺CD8⁺ T cells 3 days later. Serial quantitative bioluminescent imaging was performed. (B) Bioluminescent images of mice. Two-minute acquisitions are shown, but shorter acquisitions were performed for signal quantitation of mice that saturated the detector. Images were assembled with the use of Illustrator (Adobe Systems). (C) Peripheral blood analysis of mice 2 days after T-cell injection. P value was obtained by 1-way ANOVA analysis. Panels A to C are representative of 2 experiments with 3 to 4 mice per group. Bar graphs and data points represent mean ± SE. (D) Comparison of leukemia bioluminescent signal and peripheral blood donor T-cell percentage of CD8 2 days after T-cell injection. Data points are individual mice from 2 experiments. In 1 of 2 experiments Leu16⁺ T cells were titrated into WT mice at 0.1, 0.3, and 10⁷ T cells/mouse.