Viral delivery of multiple miRNAs promotes retinal ganglion cell survival and functional preservation after optic nerve crush injury

Research output: Contribution to journalArticlepeer-review

Authors

  • Ben Mead
  • Erin Cullather
  • Naoki Nakaya
  • Yuzhe Niu
  • Christo Kole
  • Stanislav Tomarev

Colleges, School and Institutes

External organisations

  • Cardiff and Vale University Health board, University Hospital of Wales, Cardiff, UK.
  • National Eye Institute
  • Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, United Kingdom.
  • Institute for Inflammation and Ageing

Abstract

Bone marrow mesenchymal stem cell (BMSC)-derived small extracellular vesicles (sEV) but not fibroblast sEV provide retinal ganglion cell (RGC) neuroprotection both in vitro and in vivo, with miRNAs playing an essential role. More than 40 miRNAs were more abundant in BMSC-sEV than in fibroblast-sEV. The purpose of this study was to test the in vitro and in vivo neuroprotective and axogenic properties of six candidate miRNAs (miR-26a, miR-17, miR-30c-2, miR-92a, miR-292, and miR-182) that were more abundant in BMSC-sEV than in fibroblast-sEV. Adeno-associated virus 2 (AAV2) expressing a combination of three of the above candidate miRNAs were added to heterogenous adult rat retinal cultures or intravitreally injected into rat eyes one week before optic nerve crush (ONC) injury. Survival and neuritogenesis of βIII-tubulin+ RGCs was assessed in vitro, as well as the survival of RBPMS+ RGCs and regeneration of their axons in vivo. Retinal nerve fiber layer thickness (RNFL) was measured to assess axonal density whereas positive scotopic threshold response electroretinography amplitudes provided a readout of RGC function. Qualitative retinal expression of PTEN, a target of several of the above miRNAs, was used to confirm successful miRNA activity. AAV2 reliably transduced RGCs in vitro and in vivo. Viral delivery of miRNAs in vitro showed a trend towards neuroprotection but remained insignificant. Delivery of selected combinations of miRNAs (miR-17-5p, miR-30c-2 and miR-92a; miR-92a, miR-292 and miR-182) before ONC provided significant therapeutic benefits according to the above measurable endpoints. However, no single miRNA appeared to be responsible for the effects observed, whilst positive effects observed appeared to coincide with successful qualitative reduction in PTEN immunofluorescence in the retina. Viral delivery of miRNAs provides a possible neuroprotective strategy for injured RGCs that is conducive to therapeutic manipulation.

Bibliographic note

Copyright © 2020 Elsevier Ltd. All rights reserved.

Details

Original languageEnglish
Pages (from-to)108071
JournalExperimental Eye Research
Volume197
Publication statusE-pub ahead of print - 20 Jun 2020