Comparison of Gene-Editing Approaches for Severe Congenital Neutropenia-Causing Mutations in the ELANE Gene

CRISPR J. 2024 Oct;7(5):258-271. doi: 10.1089/crispr.2024.0006.

Abstract

Safety considerations for gene therapies of inherited preleukemia syndromes, including severe congenital neutropenia (CN), are paramount. We compared several strategies for CRISPR/Cas9 gene editing of autosomal-dominant ELANE mutations in CD34+ cells from two CN patients head-to-head. We tested universal and allele-specific ELANE knockout, ELANE mutation correction by homology-directed repair (HDR) with AAV6, and allele-specific HDR with ssODN. All strategies were not toxic, had at least 30% editing, and rescued granulopoiesis in vitro. In contrast to published data, allele-specific indels in the last exon of ELANE also restored granulopoiesis. Moreover, by implementing patient-derived induced pluripotent stem cells for GUIDE-Seq off-target analysis, we established a clinically relevant "personalized" assessment of off-target activity of gene editing on the background of the patient's genome. We found that allele-specific approaches had the most favorable off-target profiles. Taken together, a well-defined head-to-head comparison pipeline for selecting the appropriate gene therapy is essential for diseases, with several gene editing strategies available.

Publication types

  • Comparative Study

MeSH terms

  • Alleles
  • CRISPR-Cas Systems*
  • Congenital Bone Marrow Failure Syndromes* / genetics
  • Congenital Bone Marrow Failure Syndromes* / therapy
  • Gene Editing* / methods
  • Genetic Therapy* / methods
  • Humans
  • Induced Pluripotent Stem Cells / metabolism
  • Leukocyte Elastase
  • Mutation*
  • Neutropenia* / congenital
  • Neutropenia* / genetics
  • Neutropenia* / therapy
  • Recombinational DNA Repair / genetics

Substances

  • ELANE protein, human
  • Leukocyte Elastase

Supplementary concepts

  • Neutropenia, Severe Congenital, Autosomal Recessive 3