Figure 6. CD19 CAR-targeted T cell dependence on conditioning chemotherapy and T cell dose.

T cells were transduced with m1928z and infused at increasing doses (noted on axes) into congenic mice (n = 40) that had been conditioned with increasing doses of cyclophosphamide (noted above columns). Peripheral blood B and congenic T cells were evaluated by flow cytometry for B and T cell markers 4 weeks after adoptive transfer. (b and c) A repeat experiment (n = 44) was done while holding cyclophosphamide conditioning constant (300 mg/kg), but with increasing T cell doses. Mice were sacrificed 1 and 5 weeks after adoptive transfer with CD19 CAR-targeted congenic T cells and flow cytometry for B cell (B220) and congenic T cells (Thy1.1/Thy1.2) was performed on single-cell suspensions of the BM and spleen. All counts and percentages were done with Countbright beads (Invitrogen). Statistical significance (p <0.05) was calculated by one-way ANOVA and is denoted by asterisks. For all sections of this figure error bars represent the SEM.