When photoreceptor cells, the light sensing cells in the eye, degenerate the result is blindness and the vision cannot be restored. But what lies behind those “dead” cells?
Researchers in Europe asked this very question and came up with a molecular “light switch” that restored vision in blind mice. Lurking behind the dead photoreceptors were healthy retina cells that normally do not respond to light. When a light sensing protein was introduced to the healthy cells they became replacement photoreceptor cells that responded to light stimulus rather than neurotransmitter signals. The result was restored vision and reaction to visual stimulus in the mice.
Human clinical trials are still a few years out, but potentially any form of blindness via dead photoreceptors could be reversed.