Doctors have taken a major step towards curing the most common form of blindness in the UK – age-related macular degeneration.
Douglas Waters, 86, could not see out of his right eye, but “I can now read the newspaper” with it, he says.
He was one of two patients given pioneering stem cell therapy at Moorfields Eye Hospital in London.
Cells from a human embryo were grown into a patch that was delicately inserted into the back of the eye.
Douglas, who is from London, developed severe age-related macular degeneration in his right eye three years ago.
The technique, published in Nature Biotechnology, starts with embryonic stem cells. These are a special type of cell that can become any other in the human body.
They are converted into the type of cell that makes up the retinal pigment epithelium and embedded into a scaffold to hold them in place.
The living patch is only one layer of cells thick – about 40 microns – and 6mm long and 4mm wide.
It is then placed underneath the rods and cones in the back of the eye. The operation takes up to two hours.
However, he does not call this a “cure” as completely normal vision is not restored.
So far the patients, the other is a woman in her early sixties, have maintained improved vision in the treated eye for a year.
They went from not being able to read with their affected eye at all, to reading 60 to 80 words per minute.
Eight more patients will take part in this clinical trial.
Doctors need to be sure it is safe. One concern is the transplanted cells could become cancerous, although there have been no such signs so far.