April 2014
Volume 55, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2014
AAV-mediated Gene Therapy Restores M-Cone Function in S-opsin only Thrb Knockout Mouse
Author Affiliations & Notes
  • Wei Du
    Ophthalmology, University of Florida, Gainesville, FL
  • Wen-tao Deng
    Ophthalmology, University of Florida, Gainesville, FL
  • Sanford L Boye
    Ophthalmology, University of Florida, Gainesville, FL
  • Jie Li
    Ophthalmology, University of Florida, Gainesville, FL
  • Wei Li
    National Eye Institute, NIH, Bethesda, MD
  • William W Hauswirth
    Ophthalmology, University of Florida, Gainesville, FL
  • Ji-Jing Pang
    Ophthalmology, University of Florida, Gainesville, FL
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 3318. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Wei Du, Wen-tao Deng, Sanford L Boye, Jie Li, Wei Li, William W Hauswirth, Ji-Jing Pang; AAV-mediated Gene Therapy Restores M-Cone Function in S-opsin only Thrb Knockout Mouse. Invest. Ophthalmol. Vis. Sci. 2014;55(13):3318.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: Color vision is facilitated by cones expressing different opsin photopigments. M-cones are sensitive to middle (M, ‘green’) and S-cones short (S,‘blue’) wavelengths. Thyroid hormone receptor β2 (TRβ2) is a ligand-activated transcription factor that is expressed in the outer nuclear layer of the embryonic retina. Thrb (encoding Trβ2) knockout (KO) mice show selective loss of M-opsin and a concomitant increase in S-opsin. Therefore the Thrb KO mouse provides a model for the study of human Blue Cone Monochromacy. We therefore tested whether AAV-mediated M-opsin gene therapy targeting S-opsin only cones can restore M-cone system function/structure in this model.

Methods: At postnatal day 14 (P14), one μl of AAV8 (Y447, 733)-IRBP/GNAT2-M-opsin vector (1013 particles/ml) was injected subretinally into one eye of each TRb2 KO mouse. The other eye was uninjected as a control. M-cone mediated ERGs were recorded at 8 weeks after injection. Treated and control eyes were harvested for immunohistochemical studies.

Results: Eight weeks after treatment, nearly normal dark-adapted ERG waveforms were recorded in either treated or untreated Thrb KO eyes with a mild reduction of ERG amplitudes in treated eyes, perhaps due to subretinal injection-related damage. Cone mediated light-adapted ERGs were recorded from either treated or untreated eyes. S-cone mediated ERGs were also recorded from either treated or untreated eyes. M-cone mediated ERGs were only seen in treated Thrb KO eyes, at about 20% of normal amplitudes. Cone-opsin staining showed that robust S-opsin was present in both treated and untreated eyes whereas no M-opsins were evident in untreated eyes. In contrast, in treated eyes M-opsin positive cells were seen, which were shown to be cones by cone-specific PNA staining.

Conclusions: Since Thrb KO mouse has only S-opsin, it can be considered a model for human Blue Cone Monochromacy. AAV8-IRBP/GNAT2-M-opsin mediated gene therapy restores M-cone function in Thrb KO mouse. These results serve as a baseline for studying long-term retinal rescue in Thrb KO mice.

Keywords: 470 color pigments and opsins • 538 gene transfer/gene therapy • 695 retinal degenerations: cell biology  
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×