A number of degenerative eye diseases are related to photoreceptors no longer functioning properly. There can be a host of reasons that photoreceptors don’t work, but soon it may not be that important to know why the disease is happening. That is because researchers at University of California, Berkeley have come up with a way of treating retinal degenerative diseases by turning cells that normally can’t sense light into ones that can.
The researchers used an inactivated virus to introduce a gene into the ganglion cells of mice suffering from macular degeneration. Normally, ganglion cells can’t see anything at all, but the gene that the researchers delivered makes cells express the medium-wavelength cone opsin, a protein that makes cells sensitive to green light. The mice were born with good vision, but it failed over time because the mice inherited macular degeneration. Before they went blind, the mice were taught to respond to different symbols on a screen. In the weeks and months after treatment, the same symbols were displayed to the mice to test whether they responded to them, indicating that they had vision.
Remarkably, the mice followed the instructions coded to them on the computer screen and this ability remained even while the ambient light changed. They were able to explore their environment and used their vision to their advantage.
Diagram of a setup in which mice were trained to respond to patterns on iPads instead of much brighter LEDs. After the trained mice went blind from an inherited retinal disease, they were treated with a gene therapy that restored sufficient sight for them to respond to patterns on the iPads almost as well as before they went blind.
Study in Nature Communications: Restoration of high-sensitivity and adapting vision with a cone opsin…