In situ regeneration of retinal pigment epithelium by gene transfer of E2F2: a potential strategy for treatment of macular degenerations

Gene Ther. 2017 Dec;24(12):810-818. doi: 10.1038/gt.2017.89. Epub 2017 Nov 30.

Abstract

The retinal pigment epithelium (RPE) interacts closely with photoreceptors to maintain visual function. In degenerative diseases such as Stargardt disease and age-related macular degeneration, the leading cause of blindness in the developed world, RPE cell loss is followed by photoreceptor cell death. RPE cells can proliferate under certain conditions, suggesting an intrinsic regenerative potential, but so far this has not been utilised therapeutically. Here, we used E2F2 to induce RPE cell replication and thereby regeneration. In both young and old (2 and 18 month) wildtype mice, subretinal injection of non-integrating lentiviral vector expressing E2F2 resulted in 47% of examined RPE cells becoming BrdU positive. E2F2 induced an increase in RPE cell density of 17% compared with control vector-treated and 14% compared with untreated eyes. We also tested this approach in an inducible transgenic mouse model of RPE loss, generated through activation of diphtheria toxin-A gene. E2F2 expression resulted in a 10-fold increase in BrdU uptake and a 34% increase in central RPE cell density. Although in mice this localised rescue is insufficiently large to be demonstrable by electroretinography, a measure of massed retinal function, these results provide proof-of-concept for a strategy to induce in situ regeneration of RPE for the treatment of RPE degeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / genetics
  • Aging / metabolism
  • Animals
  • Cell Proliferation / genetics
  • Diphtheria Toxin / genetics
  • Disease Models, Animal
  • E2F2 Transcription Factor / genetics*
  • Gene Transfer Techniques*
  • Genetic Therapy*
  • Genetic Vectors
  • Macular Degeneration / therapy*
  • Mice
  • Mice, Transgenic
  • Peptide Fragments / genetics
  • Regeneration
  • Retinal Pigment Epithelium / cytology
  • Retinal Pigment Epithelium / metabolism
  • Retinal Pigment Epithelium / physiopathology*

Substances

  • Diphtheria Toxin
  • E2F2 Transcription Factor
  • E2f2 protein, mouse
  • Peptide Fragments
  • diphtheria toxin fragment A