American scientists from the National Eye Institute (NEI) in Bethesda were able to cure mice of congenital blindness by reprogramming retinal cells into photoreceptors.
In order to see, both we and mice need photoreceptors — light-sensitive neurons located in the retina of the eye. In addition to rods, cones and other cells, auxiliary, so-called Müller’s glial cells are also part of the retina.
These cells are known to have a high regenerative potential. Moreover, with injuries, they can turn into photoreceptors. For example, in a zebrafish in this way, it is possible to restore sight after damage to the retina.
In their studies, scientists have moved from fish to mice, which are much closer to the person on the device eye. During the experiments, scientists stepped up the work of Müller cells in the eyes of mice born blind. That is, these animals did not have photo-receptor sticks at all.
Indeed, it turned out that you can force Muller cells to transform into the right photoreceptors, which will work just as effectively as real sticks. The contacts of newly formed photoreceptors with other types of nerve cells and the formation of synapses between them, a specific form of connection between neurons, were recorded. The rods have actually integrated into the path from the retina to the visual cortex in the brain.
At the moment, scientists are checking how mice with new vision are oriented in the maze. If the experiments are successful, the new method of regenerative therapy in the future can be used to treat age-related macular degeneration and pigmentary retinitis.