New type of cell could be used to reverse sight loss

A study in the United States has demonstrated that fibroblasts (cells involved in healing after injury) could be reprogrammed into light-sensitive photoreceptor-like cells and used to reverse sight loss, according to a report in the journal Nature.

The research team, based at the University of North Texas Health Science Centre and the National Eye Institute, National Institutes of Health, Bethesda, used a set of five small molecules to chemically transform the cells. 

It takes up to six months to create replacement photoreceptor cells from stem cells. This new technique may re-programme photoreceptor-like cells within 10 days.

The research was conducted in mice bred to have retinal degeneration, and the team is now focused on preparing to begin research in people. 

Commenting on the work at the NEI, Dr Anand Swaroop said: “This is the first study to show that direct, chemical reprogramming can produce retinal-like cells, which gives us a new and faster strategy for developing therapies for age-related macular degeneration (AMD) and other retinal disorders caused by the loss of photoreceptors.”

The researchers admit that there are still hurdles to overcome before this technology could restore the sight of people with macular disease: only a small proportion of fibroblasts are converted into photoreceptors, and they do not spread out across the retina to repair larger areas of damage.

In the paper, the researchers concluded that: “Although Chemically induced Photoreceptor-like Cells (CiPCs) have therapeutic potential, a lack of proliferation – as is the case for native photoreceptors – and low conversion efficiency are the main impediments for a translational application. We anticipate that optimisation of our current protocol may be beneficial for obtaining large numbers of CiPCs. Overall, CiPCs are a promising cell-replacement candidate and may lead to a scalable therapy for vision restoration.”