Reaching Rods With Gene Therapy (IMAGE) University of Pennsylvania Caption This is a canine retina, injected with an AAV2/5 carrying the GRK1 promoter and the GFP gene. A red antibody that specifically identifies cones was used to label this class of photoreceptor cells, and confirm that GFP targeted rods. Blue labeling identifies the retina cells. Credit University of Pennsylvania Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.