Figure 2. Primary human T cells transduced to DHFR^FS/IMPDH2^IY transgenes are resistant to MTX and MPA.

Non-transduced T cells (non-Txd; grey line/bar) and immunomagnetically-enriched EGFRt⁺ T cells (99.5% EGFRt⁺; Txd+Enr; black line/bar) were plated on day 8 at the indicated concentrations of MTX (a), MPA (b), and a combination of MTX+ MPA (c), cells were followed for total viable cell number, percentage of viable cells, and fold expansion for12 days. Equal numbers of cells were plated in triplicate wells of 24-well plates. The data represent the mean ± S.D. There was a significant difference in viability and fold expansion at day 12 between the non-transduced (Non-Txd) and the transduced, EGFRt-enriched T cells (Txd+Enr) at each drug concentration. ***, p≤0.0002; **, p≤0.001; *, p≤0.01. The data are representative of three separate experiments.