We see thanks to photoreceptors - cells on the retina of the eye. They react to light and send signals to the brain to interpret the image. Vision is impaired if these cells are damaged. In mammals, to which humans belong, they cannot regenerate on their own. However, there is a fish in which these cells are regenerated, on the basis of which scientists have created a "cure for blindness" and tested it in mice.
The Danio fish can restore its vision thanks to the special Müller glia cells, which help to renew photoreceptors. Scientists have tried to recreate the same process in mammals, which are not capable of such regeneration.
At the first stage, a genome was introduced into the eyes of the mice, which included the beta-catenin protein. It allows Müller glia cells to start dividing. The second step was to transform these cells into structural rods. For this, two weeks later, special injections were introduced into the retina.
Upon further examination of the cells with a microscope, it turned out that the structural rods grown from Müller glia look exactly like natural ones. In addition, they have established communication with other neurons and are fully integrated into the visual apparatus. Tests on mice with congenital blindness, in which cells are completely absent, have also shown positive results. The research holds promise for a cure for a myriad of vision-related illnesses.