Cure for blindness 'edges closer'
Published on 22 July 2013 11:30 AM
Researchers say a 'huge leap forward' has been made for the prospects of reversing blindness.
In an animal study, scientists at Moorfields Eye Hospital and University College London have discovered that the part of the eye which actually detects light can be repaired using stem cells.
As a result of this 'significant breakthrough', they believe that human trials are now for the first time a real possibility.
Professor Robin Ali, lead researcher, claims 5 years is a realistic aim for starting a clinical trial involving photoreceptors - the cells in the retina which react to light and convert it into an electrical signal which can be sent to the brain.
These cells can die off in some cases of blindness such as Stargardt's disease and age-related macular degeneration, although there are already trials in people to use stem cells to replace the 'support' cells in the eye which keep the photoreceptors alive
But now the London-based team has raised the prospect of reversing blindness by showing it is possible to replace the light-sensing cells themselves.
The study showed that these cells could hook up with the existing architecture of the eye and begin to function. It used a new technique whereby thousands of stem cells, which were primed to transform into photoreceptors, were injected into the eyes of blind mice.
However, only about 1,000 cells out of a transplant of 200,000 actually hooked up with the rest of the eye - and this level of effectiveness is a concern for Professor Chris Mason from University College London.
'I think they have made a major step forward here, but the efficiency is still too low for clinical uses,' he said.
'At the moment the numbers are tiny, and it will take quite a bit of work to get the numbers up - and then the next question is "Can you do it in man?"
'But I think it is a significant breakthrough, which may lead to cell therapies and will give a much expanded knowledge on how to cure blindness.'
The research was published in Nature Biotechnology.
Copyright Press Association 2013