Borot Florence, Humbert Olivier, Newby Gregory A, Fields Emily, Kohli Sajeev, Radtke Stefan, Laszlo George S, Mayuranathan Thiyagaraj, Ali Abdullah Mahmood, Weiss Mitchell J, Yen Jonathan S, Walter Roland B, Liu David R, Mukherjee Siddhartha, Kiem Hans-Peter
bioRxiv. 2023 Feb 23:2023.02.23.529353. doi: 10.1101/2023.02.23.529353.
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 , 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. , 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.
对正常细胞的靶向毒性是靶向免疫疗法和基因疗法的一个主要安全问题。在此，我们开发了一种碱基编辑（BE）方法，利用自然存在的CD33单核苷酸多态性，导致编辑细胞上全长CD33表面表达的去除。在人类和非人类灵长类动物（NHP）造血干细胞和祖细胞（HSPC）中进行CD33编辑可免受CD33靶向治疗的影响，而不影响正常造血，从而证明了具有降低白血病外毒性的新型免疫疗法的潜力。为了更广泛地应用于基因治疗，我们展示了对CD33和γ珠蛋白基因进行高效（>70%）的多重腺嘌呤碱基编辑，导致双基因编辑细胞在NHP中长期存在并伴有HbF重新激活。此外，双基因编辑细胞可以通过用CD33抗体-药物偶联物吉妥珠单抗奥唑米星（GO）处理来富集。总之，我们的结果突出了腺嘌呤碱基编辑器在改进免疫疗法和基因疗法方面的潜力。
