Retinal regeneration

The roles of a few important elements are summarized below:[3][4][5][6][7] Rod precursor differentiation is another mechanism by which zebrafish can replace lost retinal neurons.

[10] More information on the signaling pathways involved is required before Muller glia mediated regeneration will be a viable treatment method for restoring vision in mammalian retinas.

In findings presented in the journal "Proceedings of the National Academy of Sciences" in 2012, a Nuffield Laboratory of Ophthalmology research team led by Dr Robert MacLaren from the University of Oxford restored sight to totally blind mice by injections of light-sensing cells into their eyes.

Researchers at Moorfields Eye Hospital had already been using human embryonic stem cells to replace the pigmented lining of the retina in patients with Stargardt's disease.

The team is also restoring vision to blind patients with an electronic retinal implant which works on a similar principle of replacing the function of the light-sensing photoreceptor cells.

The device may help adults with RP who have lost the ability to perceive shapes and movement to be more mobile and to perform day-to-day activities.

Rods, cones and nerve layers in the retina. The front (anterior) of the eye is on the left. Light (from the left) passes through several transparent nerve layers to reach the rods and cones (far right). A chemical change in the rods and cones send a signal back to the nerves. The signal goes first to the bipolar and horizontal cells (yellow layer), then to the amacrine cells and ganglion cells (purple layer), then to the optic nerve fibres. The signals are processed in these layers. First, the signals start as raw outputs of points in the rod and cone cells. Then the nerve layers identify simple shapes, such as bright points surrounded by dark points, edges, and movement. (Based on a drawing by Ramón y Cajal .)
Section through retina
Section through retina