Scientists at Manchester University have succeed in restoring vision for blind mice by reprogramming the deeper cells in their eyes.
Co-leading scientist Rob Lucas says human trials may begin as early as in five years, the New Scientist reports.
The therapy aims to reprogram cells deep within the retina to capture light, such as ganglion and bipolar cells. Their normal function does not include the recognition of light, but rather the processing of signals for the brain.
By attaching the human cell for rhodopsin (a pigment used to detect brightness) to a virus, it can reach these deeper cells and enable them to recognise brightness to a certain extent.
Although the mice used in the trials responded under normal light conditions, the detail of their vision remained impaired. “The treated mice could discriminate black and white bars, but only ones that were 10 times thicker than what sighted mice could see,” the New Scientist quoted Lucas.
Scientist Robin Ali of University College London called the discovery, “the most effective example yet” of how retinal degeneration may be treated through genetic therapy.
Retinal degeneration is a painless loss vision, due to damage to rods and cones. This may be caused by artery or vein occlusion, Retinitis pigmentosa (RP), diabetic retinopathy or specific hereditary diseases. If degenerated severely, photoreceptive cells may become damaged beyond repair, leading to – up until now – irreversible blindness.