A Versatile Reporter Platform for Evaluating HDR- and NHEJ-Based Genome Editing in Airway Epithelial Cell Cultures Using an rAAV Vector

Viruses. 2025 Jun 6;17(6):821. doi: 10.3390/v17060821.

Abstract

Therapeutic gene editing strategies utilize endogenous DNA repair pathways-nonhomologous end joining (NHEJ) or homology-directed repair (HDR)-to introduce targeted genomic modifications. Because HDR is restricted to dividing cells, whereas NHEJ functions in both dividing and non-dividing cells, NHEJ-based approaches are better suited for in vivo gene editing in the largely post-mitotic airway epithelium. Homology-independent targeted insertion (HITI), an NHEJ-based method, offers a promising strategy for cystic fibrosis (CF) gene therapy. Here, we applied HITI to drive the expression of a promoterless reporter through an exon trap strategy in both proliferating airway basal cells and well-differentiated primary airway epithelial cultures derived from transgenic ROSAmTmG ferrets. We also established a versatile human gene editing reporter (GER) airway basal cell line capable of multipotent differentiation, enabling real-time visualization of editing outcomes and the quantitative assessment of HDR- and NHEJ-based editing efficiencies. Together, these platforms provide easily accessible tools for optimizing genome editing strategies in the respiratory epithelium and advancing clinically relevant delivery strategies for CF gene therapy.

Keywords: adeno-associated virus vector; airway epithelial cultures; gene editing; reporter cell lines.

MeSH terms

  • Animals
  • Cell Line
  • Cells, Cultured
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis / therapy
  • DNA End-Joining Repair*
  • Dependovirus* / genetics
  • Epithelial Cells* / metabolism
  • Ferrets
  • Gene Editing* / methods
  • Genes, Reporter*
  • Genetic Therapy / methods
  • Genetic Vectors* / genetics
  • Humans
  • Recombinational DNA Repair*
  • Respiratory Mucosa / cytology