Improved Intravitreal AAV-Mediated Inner Retinal Gene Transduction after Surgical Internal Limiting Membrane Peeling in Cynomolgus Monkeys

Mol Ther. 2017 Jan 4;25(1):296-302. doi: 10.1016/j.ymthe.2016.10.008. Epub 2017 Jan 4.


The retina is an ideal target for gene therapy because of its easy accessibility and limited immunological response. We previously reported that intravitreally injected adeno-associated virus (AAV) vector transduced the inner retina with high efficiency in a rodent model. In large animals, however, the efficiency of retinal transduction was low, because the vitreous and internal limiting membrane (ILM) acted as barriers to transduction. To overcome these barriers in cynomolgus monkeys, we performed vitrectomy (VIT) and ILM peeling before AAV vector injection. Following intravitreal injection of 50 μL triple-mutated self-complementary AAV serotype 2 vector encoding EGFP, transduction efficiency was analyzed. Little expression of GFP was detected in the control and VIT groups, but in the VIT+ILM group, strong GFP expression was detected within the peeled ILM area. To detect potential adverse effects, we monitored the retinas using color fundus photography, optical coherence tomography, and electroretinography. No serious side effects associated with the pretreatment were observed. These results indicate that surgical ILM peeling before AAV vector administration would be safe and useful for efficient transduction of the nonhuman primate retina and provide therapeutic benefits for the treatment of retinal diseases.

Keywords: cynomolgus; glaucoma; internal limiting membrane; intravitreous injection; retina; triple-mutated AAV.

MeSH terms

  • Animals
  • Dependovirus / genetics*
  • Electroretinography
  • Ependymoglial Cells / metabolism
  • Ependymoglial Cells / pathology
  • Female
  • Fluorescein Angiography
  • Gene Expression
  • Gene Transfer Techniques
  • Genes, Reporter
  • Genetic Therapy
  • Genetic Vectors / administration & dosage
  • Genetic Vectors / genetics*
  • Inflammation / genetics
  • Inflammation / metabolism
  • Inflammation / pathology
  • Intravitreal Injections
  • Macaca fascicularis
  • Retina / metabolism*
  • Retina / pathology
  • Tomography, Optical Coherence
  • Transduction, Genetic*
  • Transgenes*