Factors governing the transduction efficiency of adeno-associated virus in the retinal ganglion cells following intravitreal injection

Gene Ther. 2019 Apr;26(3-4):109-120. doi: 10.1038/s41434-019-0060-0. Epub 2019 Jan 28.

Abstract

Efficient transduction of the retinal ganglion cells (RGCs) is a prerequisite to maximize therapeutic outcomes in any form of gene therapy for optic neuropathies. Whereas subretinal injection of adeno-associated virus 2 (AAV2) has been well-characterized, the serotype, viral load, and promoter combinations that govern RGC transduction efficiency following intravitreal injection remains poorly understood. We evaluated the transduction efficiency of seven AAV2 serotypes (AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9) for the RGCs at 4 weeks following intravitreal injection in C57BL/6J mice. Intravitreal injection of 1 × 109 vg of AAV2/2 with eGFP driven by the CMV promoter attained a higher transduction efficiency for the RGCs (60.0 ± 4.2%) compared with the six other AAV2 serotypes with eGFP driven by the same promoter injected at the same viral load ( < 3.0%). Reporter driven by the CAG promoter had a lower transduction efficiency (up to 42.0 ± 5.8%) compared with that driven by the CMV reporter (60.0 ± 4.2%, p ≤ 0.024). There was a viral dose-dependent transduction effect of AAV2/2-CMV-eGFP and the transduction efficiency was 40.2 ± 3.9%, 16.6 ± 4.2%, and 2.6 ± 0.2% when the viral load decreased to 5 × 108 vg, 1 × 108 vg, and 1 × 107 vg, respectively. Optimizing viral serotype, viral load, and promoter construct of AAV2 is important to maximize transgene expression in RGC-targeted gene therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dependovirus
  • Genetic Therapy / methods*
  • Genetic Vectors / genetics
  • Green Fluorescent Proteins / genetics
  • Intravitreal Injections
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Parvovirinae / genetics
  • Retina / metabolism
  • Retinal Ganglion Cells / drug effects*
  • Retinal Ganglion Cells / metabolism
  • Transduction, Genetic / methods*

Substances

  • Green Fluorescent Proteins

Supplementary concepts

  • Adeno-associated virus-2