Scientists at University College London's Institute of Ophthalmology have unveiled 'stunning' new research where retinal cell transplants have successfully restored vision in mice.
The paper, published in yesterday's edition of Nature, shows that non-dividing retinal cells implanted into adult mouse retina can generate new photoreceptors, suggesting a possible method of regenerating photoreceptors lost in eye conditions such as age-related macular degeneration.
Previously, stem cells transplanted into adult retinas have not integrated correctly and it was thought the retinal environment inhibits regeneration.
But Professor Robin Ali from UCL and colleagues have extracted immature retinal cells from newborn mice - at a time when main rod photoreceptors are normally being generated - and transplanted them into adult mouse retinas. Another author, Dr Jane Sowden, said: 'Remarkably we found that the mature retina, previously believed to have no capacity for repair, is in fact able to support the development of new functional photoreceptors.'
Professor Ali said: 'Recent research has shown that a population of cells can be found on the margin of the adult retina which have stem cell-like properties, in other words they are capable of self-renewal.
'These could be harvested through minor surgery and grown in the lab to become photoreceptor precursors before being re-implanted on the retina.'
To harvest human retinal cells at the same developmental stage as used in this study, however, would involve taking cells from a foetus in the second trimester of pregnancy.
But Dr Robert MacLaren, a specialist at Moorfields Eye Hospital who worked on the research, said they did not want to do that. He said the aim would be to look at adult stem cells to see if they could be genetically altered to behave like the mouse retinal cells.
Andrew Dick, professor of ophthalmology at the University of Bristol, said that as with any basic research we have to be careful not to over-hype. 'However, this is a stunning piece of research,' he told the BBC.
