Fig. 2: ABE8e edited HSPCs are resistant to CD33-targeted therapy in vitro and in vitro differentiated CD33^Δ2-edited myeloid cells display intact phagocytic capacity.

a In vitro differentiated unedited (UE) or CD33^Δ2-edited monocytes show comparable phagocytosis capacity, as measured by E.coli bioparticles internalization. Left, Representative FACs plots of E. coli bioparticles internalization. Treatment with actin polymerization inhibitor, cytochalasin D, abrogates phagocytosis. Right, Graph of phagocytosis quantification. Unpaired two-tailed t-test. b CD33^Δ2-edited CD34⁺ cells resist Gemtuzumab Ozogamicin (GO) cytotoxicity in vitro. Cells were incubated 48 h with GO and cytotoxicity analyzed by FACS using Sytox Blue or 7AAD as a viability dye. CD33 ^Δ2-edited CD34⁺ show same resistance to GO cytotoxicity than a donor with homozygous rs12459419 A14V SNP (TT genotype). Error bars show ±SEM. (2 independent experiments, 2 donors, run in triplicates) c, ML1 CD33 WT or KO cells and Unedited, or ABE8e-edited mPB CD34⁺ cells were assessed for resistance to the CD33/CD3 bispecific T-cell engager (BiAb, generated from published sequences and described in Correnti et al⁶¹.). Target cells were incubated with healthy donor T cells for 2 days and absolute cell number and viability were detected by flow cytometry analysis following staining with 4’,6-diamidino-2-phenylindole (DAPI). Results were normalized to reactions that were not treated with the drug (1 experiment run in triplicates, 1 donor). Source data are provided as a Source Data file.