A) Cells underwent successful dual transduction followed by mRNA TALEN transfection for development of CD3/TcR^- CD19CAR⁺EGFRt⁺ CNA22-IMPDH2Δ-HER2tG⁺ T cells. B) Transduced T cells underwent selection for their respective markers, were stimulated and cultured for 21 days at varying MPA concentrations. Cells transduced to express IMPDH2Δ exhibited improved expansion as compared to CD19CAR and mock control cells. Data was normalized to the cell group's no drug control expansion. C) Following co-culture with K562-CD19 antigen cells with CSA concentrations of 0-1000ng/ml CD19CAR cells transduced with the drug resistant vector secreted significantly increased IFNg and IL-2 levels compared to CD19CAR only cells. NS = not significant; Horizontal bars indicate statistical significance defined as p-value <0.05.