Researchers, for the first time, have not only developed the photo-receptors of the eye in the dish from stem cells but also transplanted them into eyes of blind mice where the cells became fully integrated into the complex retinal tissue.
Scientists may have been unable to show any improvement in the vision of the blind mice, however, they are confident that this will soon be possible in further experiments.
The technique could lead to stem cell transplants for improving the vision of thousands of people with degenerative eye disorders caused by the progressive loss of photosensitive cells, scientists said.
"The breakthrough here is that we've demonstrated we can transplant photo-receptors derived from embryonic stem cells into adult mice. It paves the way to a human clinical trial because now we have a clear route map of how to do it," said Professor Robin Ali of University College London, who led the research at the Institute of Ophthalmology and Moorfields Eye Hospital.
Doing so allowed the rod cells to develop the complex three-dimensional structure that is important for them to function correctly, the report said.
"The new 3D technique more closely mimics normal development, which means we are able to pick out and purify the cells at precisely the right stage to ensure successful transplantation. The next step will be to refine this technique using human cells to enable us to start clinical trials," Ali said.