Lentiviral gene therapy for X-linked chronic granulomatous disease recapitulates endogenous CYBB regulation and expression

Blood. 2023 Mar 2;141(9):1007-1022. doi: 10.1182/blood.2022016074.

Abstract

X-linked chronic granulomatous disease (X-CGD) is a primary immunodeficiency caused by mutations in the CYBB gene, resulting in the inability of phagocytic cells to eliminate infections. To design a lentiviral vector (LV) capable of recapitulating the endogenous regulation and expression of CYBB, a bioinformatics-guided approach was used to elucidate the cognate enhancer elements regulating the native CYBB gene. Using this approach, we analyzed a 600-kilobase topologically associated domain of the CYBB gene and identified endogenous enhancer elements to supplement the CYBB promoter to develop MyeloVec, a physiologically regulated LV for the treatment of X-CGD. When compared with an LV currently in clinical trials for X-CGD, MyeloVec showed improved expression, superior gene transfer to hematopoietic stem and progenitor cells (HSPCs), corrected an X-CGD mouse model leading to complete protection against Burkholderia cepacia infection, and restored healthy donor levels of antimicrobial oxidase activity in neutrophils derived from HSPCs from patients with X-CGD. Our findings validate the bioinformatics-guided design approach and have yielded a novel LV with clinical promise for the treatment of X-CGD.

MeSH terms

  • Animals
  • Genetic Therapy / methods
  • Granulomatous Disease, Chronic* / genetics
  • Granulomatous Disease, Chronic* / therapy
  • Mice
  • Mutation
  • NADPH Oxidase 2 / genetics
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism

Substances

  • NADPH Oxidases
  • NADPH Oxidase 2
  • Cybb protein, mouse