Scientists use gene therapy and a novel light-sensing protein to restore vision in mice

The National Eye Institute, part of the National Institutes of Health, had provided a research grant to Nanoscope, LLC for their development of MCO1. MCO1 opsin is a newly created light-sensing protein that was able to restore vision in blind mice when it was introduced to the retina bipolar cells using gene therapy. Opsins are proteins that are part of the visual process. They signal other cells as part of a pathway of signals necessary for vision. Opsins are expressed by the photoreceptors in the retina. When photoreceptors are activated by light, they pulse and send signals to nerves in the eye. There are eye diseases, including retinitis pigmentosa where the photoreceptors are damaged. This impairs vision. Although the photoreceptors are damaged, there are still other working cells in the eye, like bipolar cells. This research found a way for these bipolar cells to do some of the work that normally would fall to the photoreceptors. In totally blind mice (no light perception) after treatment with MCO1, they were observed to gain significant retinal function and vision. This therapy could be simpler than other existing treatments. It only requires a one-time injection into the eye and no other equipment is needed. This can be an alternative to retinal prosthesis. MCO1 is also sensitive to ambient light so there does not need to be strong light shining into the eye that might result in damage to the cells. This can also treat a wider range of degenerative retinal diseases. Nanoscope is planning on a US clinical trial.

What this means for Usher syndrome: As vision loss in Usher syndrome is caused by retinitis pigmentosa, this could be a possible therapy for vision loss in the future. It needs to undergo further research in humans but if it proves to be successful, it could be a simpler one-time only injection treatment for vision loss.

Link to original article