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bioRxiv · 10.1101/2023.02.23.529353

Multiplex Base Editing to Protect from CD33-Directed Therapy: Implications for Immune and Gene Therapy

Borot, F.·Humbert, O.·Newby, G. A.·Fields, E.·Kohli, S.·Radtke, S.·Laszlo, G. S.·Mayuranathan, T.·Ali, A. M.·Weiss, M. J.·Yen, J. S.·Walter, R. B.·Liu, D. R.·Mukherjee, S.·Kiem, H.-P.
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Abstract

On-target toxicity to normal cells is a major safety concern with targeted immune and gene therapies. Here, we developed a base editing (BE) approach exploiting a naturally occurring CD33 single nucleotide polymorphism leading to removal of full-length CD33 surface expression on edited cells. CD33 editing in human and nonhuman primate (NHP) hematopoietic stem and progenitor cells (HSPCs) protects from CD33-targeted therapeutics without affecting normal hematopoiesis in vivo, thus demonstrating potential for novel immunotherapies with reduced off-leukemia toxicity. For broader applications to gene therapies, we demonstrated highly efficient (>70%) multiplexed adenine base editing of the CD33 and gamma globin genes, resulting in long-term persistence of dual gene-edited cells with HbF reactivation in NHPs. In vitro, dual gene-edited cells could be enriched via treatment with the CD33 antibody-drug conjugate, gemtuzumab ozogamicin (GO). Together, our results highlight the potential of adenine base editors for improved immune and gene therapies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/529353v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@70c99dorg.highwire.dtl.DTLVardef@c46ef4org.highwire.dtl.DTLVardef@505fd2org.highwire.dtl.DTLVardef@c30b8c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Borot, F., Humbert, O., Newby, G. A., Fields, E., Kohli, S., Radtke, S., Laszlo, G. S., Mayuranathan, T., Ali, A. M., Weiss, M. J., Yen, J. S., Walter, R. B., Liu, D. R., Mukherjee, S., Kiem, H.-P.. 2023-02-23. Multiplex Base Editing to Protect from CD33-Directed Therapy: Implications for Immune and Gene Therapy. https://doi.org/10.1101/2023.02.23.529353

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