Gene correction for SCID-X1 in long-term hematopoietic stem cells

Abstract
Gene correction in human long-term hematopoietic stem cells (LT-HSCs) could be an effective therapy for monogenic diseases of the blood and immune system. Here we describe an approach for X-linked sSevere cCombined immunodeficiency (SCID-X1) using targeted integration of a cDNA into the endogenous start codon to functionally correct disease-causing mutations throughout the gene. Using a CRISPR-Cas9/AAV6 based strategy, we achieve up to 20% targeted integration frequencies in LT-HSCs. As measures of the lack of toxicity, we observe no evidence of abnormal hematopoiesis following transplantation and no evidence of off-target mutations using a high-fidelity Cas9 as a ribonucleoprotein complex. We achieve high levels of targeting frequencies (median 45%) in CD34+ HSPCs from six SCID-X1 patients and demonstrate rescue of a lymphopoietic defect in a patient-derived HSPC population in vitro and in vivo. In sum, our study provides specificity, toxicity and efficacy data supportive of clinical development of genome editing to treat SCID-Xl.

Pavel-Dinu, Mara, et al. “Gene correction for SCID-X1 in long-term hematopoietic stem cells.” Nature Communications 10.1 (2019): 1634.s.

Methods Highlight:

PeproTech products used 

  • Animal-Free Recombinant Human SCF (AF-300-07)
  • Animal-Free Recombinant Human Flt3-Ligand (AF-300-19)
  • Recombinant Human IL-7 (200-07)
  • Animal-Free Recombinant Human IL-3 (200-03)
  • Animal-Free Recombinant Human GM-CSF (AF-300-03)
  • Animal-Free Recombinant Human TPO (AF-300-18)
  • Recombinant Human EPO (100-64)
  • Animal-Free Recombinant Human IL-15 (AF-200-15)
  • Recombinant Human IL-6 (200-06)
  • Recombinant Human IL-2 (200-02)