Senescence and inflammation are unintended adverse consequences of CRISPR-Cas9/AAV6 mediated gene editing in hematopoietic stem cells [NHEJ]

Gene editing (GE) using homology-directed repair (HDR) in hematopoietic stem and progenitor cells (HSPCs) offers promise for long-range gene correction of inherited genetic disorders. However, adverse cellular responses induced by CRISPR-Cas9/AAV6 engineering impair the long-term repopulating potential of HDR-edited HSPCs, limiting clinical translation. Our study uncovers a senescence-like response in genetically-engineered HSPCs triggered by p53 and IL-1/NF-κB activation, which restricts graft size and clonal diversity in long-term transplantation assays. We show that transient p53 inhibition or blocking inflammatory pathways can mitigate senescence-associated responses, enhancing the repopulating capacity of edited HSPCs. Importantly, we identify Anakinra, an IL-1 signaling antagonist, as a safer and effective strategy to enhance polyclonal output in HDR-edited cells while minimizing genotoxicity risks associated with the gene-editing procedure. These findings present strategies to overcome key hurdles in HDR-based HSPC therapies, providing a framework for enhancing the efficacy and safety of these approaches in future clinical applications. Targeted deep sequencing on Bone Marrow HSPC donors, treated with different editing conditions (i.e., standard editing, + ANAK, +GSE56, adn +SC514).