From: Targeting the Nrf2 Signaling Pathway in the Retina With a Gene-Delivered Secretable and Cell-Penetrating Peptide Invest. Ophthalmol. Vis. Sci.. 2016;57(2):372-386. doi:10.1167/iovs.15-17703 Figure Legend: Expression of the sGFP-TatNrf2mer AAV vector in mice retinas is safe. (A) Map of the pTR-smCBA-sGFP-TatNrf2mer AAV vector. The coding sequence of the secretable and cell-penetrating peptide was cloned in an AAV plasmid containing the small CMV enhancer/chicken β-actin hybrid promoter which is constitutively active in most cells within the retina. (B) Expression of sGFP-TatNrf2mer gene within the retina. C57BL/6J mice were intravitreally injected with 3 × 109 vector genome copies (vgc) of AAV2-QUAD(Y-F)-T497V vector delivering either GFP or sGFP-TatNrf2mer. Three weeks after vector injection, gene expression was detected by fluorescence funduscopy. Representative fundus images demonstrate that, in contrast to the localized fluorescence expression of GFP, eyes injected with sGFP-TatNrf2mer showed a diffused fluorescence consistent with the secretion of GFP. (C) Two weeks after viral vector injection, mice were evaluated by SD-OCT to detect changes within the different layers of the retina. Representative images of retinas transduced with AAV vectors delivering GFP (top) or sGFP-TatNrf2mer (bottom). (D) Quantification of the different retina layers. The thickness of each layer was measured using the segmentation analysis of Diver 2.0 software from Bioptigen. No statistically significant difference was observed in any layer between eyes injected with GFP or sGFP-TatNrf2mer vector. (E) TatNrf2mer expression within the retina was not deleterious to the electrophysiological activity of the tissue. Injected mice were evaluated by ERG to detect any differences in amplitude between the expression of GFP and sGFP-TatNrf2mer. Eyes injected with the sGFP-TatNrf2mer AAV vector had statistically significant higher a-wave and c-wave amplitudes (P < 0.05) when compared to eyes injected with the GFP AAV vector. ERG b-wave amplitudes also were elevated but did not reach statistical significance (P = 0.062). Values are reported as average ± SEM (n = 10 mice). Date of download: 1/2/2018 The Association for Research in Vision and Ophthalmology Copyright © 2018. All rights reserved.