Presence of exhaustion markers on CD19 CAR T cells. (A) Mean fluorescence and percentage positive of PD-1 on CD3⁺CD34⁺ cells transduced either after IL-7 culture or CD3 activation. MFI ∗P = .0185; percent positive ∗∗P = .0015. (B) Mean fluorescence and percentage positive of TIM-3 on CD3⁺CD34⁺ cells transduced either after IL-7 culture or CD3 activation. MFI ∗∗∗P = .0003; percent positive ∗∗∗P < .0001. (C) Mean fluorescence and percentage positive of LAG-3 on CD3⁺CD34⁺ cells transduced either after IL-7 culture or CD3 activation. MFI ∗P = .0288; percent positive ∗∗P = .0039. (D) Mean fluorescence and percentage positive of CTLA-4 on CD3⁺CD34⁺ cells transduced either after IL-7 culture or CD3 activation. MFI ∗P = .0288; percent positive P = .1230. Graphs depict each data point from 10 donors with lines connecting data points from an individual donor. Statistics were calculated by 2-tailed Wilcoxon rank sum test. MFI, mean fluorescence intensity.