Fig. 5: Dual FLT3/CD123 epitope editing enables more effective AML immunotherapies.
From: Epitope editing enables targeted immunotherapy of acute myeloid leukaemia
a, The efficiency of multiplex FLT3N399CD123S59 editing measured on bulk HSPCs or FACS-sorted subsets. Data are mean ± s.d. Statistical analysis was performed using one-way ANOVA. b, Representative plots of dual FLT3/CD123 reporter cells showing loss of recognition by 4G8 and 7G3 monoclonal antibodies after multiplex editing. OE, overexpressed. c, Single- or dual-edited K562 reporters were FACS-sorted and co-cultured with dual-specificity FLT3/CD123 CAR T cells at different effector:target (E:T) ratios. The fraction of live target cells (left) and T cell activation (CD69+; right) are shown. Statistical analysis was performed using two-way ANOVA; the comparisons are reported in Supplementary Table 24. d, Representative plots of BM samples from mice engrafted with HSPCs only, HSPCs + PDX-2 or HSPCs + PDX-2 treated with 4G8/CSL362 CAR T cells. Plots were pregated on total hCD45+; CAR T cells were identified by CD3 and AML PDXs by mNeonGreen. e, The percentage of PDX cells within hCD45+CD3− BM cells of mice transplanted and treated as indicated. Data are mean ± s.d. Statistical analysis was performed using one-way ANOVA with correction for multiple comparisons. f, FLT3 (left) and CD123 (right) editing efficiencies measured on peripheral blood (week 9–10) and sorted CD33+ and CD19+ BM fractions at the end point. Data are mean ± s.d. Statistical analysis was performed using multiple unpaired t-tests. g, The absolute counts of progenitors (left) and myeloid (middle) and lymphoid (right) subsets in the BM. Untreated mice were pooled (grey bars), CAR-treated FLT3N399CD123S59 mice are shown in pink and CAR-treated AAVS1BE mice are shown in blue. The fold change in the absolute counts (FLT3N399CD123S59/AAVS1) for CAR-treated groups is reported above each population. Data are mean ± s.d. Statistical analysis was performed using one-way ANOVA. False-discovery rate (FDR)-adjusted P values of the comparison between the FLT3N399CD123S59 and AAVS1BE conditions treated with CAR T cells are reported. Full counts are provided in Supplementary Table 23. PMN, polymorphonucleate granulocytes; prolymph., prolymphocytes.
