Big leap made in curing blindness
An animal study published in the journal Nature Biotechnology has found that stem cells can repair a part of the eye that detects light and could eventually reverse blindess. Scientists are describing this finding as a "significant breakthrough," and expect human trials to be a realistic prospect.
The retina houses photoreceptor cells that react to light and convert it to an electrical signal that is then sent to the brain. Certain diseases, such as age-related macular degeneration and Stargardt's disease, can cause these cells to die off and potentially cause blindness. In current human trials, scientists are using stem cells to replace "support cells" in the eye to keep the photoreceptors alive.
For the study, researchers used a new technique for building retinas in the laboratory. They collected thousands of stem cells, which were then primed to become photoreceptors before injecting them into the eyes of blind mice. They found that the cells were able to sync with the architecture of the eye and begin to function. Unfortunately the effectiveness is still low, with only 1,000 cells out of 200,000 that actually functioned with the rest of the eye.
But the researchers said the study provided proof of concept that photoreceptors can be transplanted from embryonic stem cells and believe a clinical trial involving humans within five years is a realistic goal.