Embryonic Stem Cells May Help Restore Sight to the Blind

Scientists have shown that light-sensitive retinal cells that have been grown in the lab from stem cells can successfully integrate into the eye when implanted into blind mice. This technique gives hope to the possibility that a similar treatment could one day help people who've become blind due to damage to their retinas to regain at least some of their sight.

Loss of photoreceptors, or light-sensitive nerve cells, is a major cause of blindness in conditions such as retinis pigmentosa, diabetes-related blindness, and age-related macular degeneration. Conditions such as these affect many people, and there is so far no effective treatment. Researchers have been exploring the possibility of somehow replacing the photoreceptors, which come in two types - rods which help to see in low light conditions, and cones, which help differentiate colors.

Robin Ali of the University College of London's Institute of Ophthalmology and Moorfields Eye Hospital led the research, and says it will be at least five years before this technique is ready for human trials. Ali is, however, confident that the treatment will reach human trials.