Stem Cells Could Cure the Most Common Cause of Irreversible Blindness 

As reported in Medical Xpress; Fight for Sight, a charity in the UK dedicated to vision, has an exciting announcement for people with macular diseases: they have just granted funding for a team at King’s College London to carry out a stem cell research project which could potentially reverse what is now irreversible blindness caused by macular diseases. This includes vision loss due to age-related macular degeneration, myopic macular degeneration, and juvenile macular dystrophies.

Macular Diseases

Macular diseases are a group of rare diseases involving the eye, the most common of which being macular degeneration. Macular degeneration is an eye disease due to failure of the macula, the part of the retina used to see fine detail such as for reading, seeing faces, colors, and motor skills like driving.

The disease has two types: wet, which can cause sudden vision loss, accounting for 10% of cases; and dry, in which patients expression gradual visual decline, making up almost 90% of cases. The main symptom is vision loss, which results in needing brighter light, difficulty reading print, and trouble recognizing faces. The disease is thought to be caused be a mix of genetic and environmental features including smoking and lack of vitamins. Macular degeneration is the most common reason for visual decline and blindness in America.

Growing Retinas from Stem Cells

 The researchers will use the study to explore using lab-grown stem cells to create mini retinas, a thin layer of light sensitive tissue on the back of the eye, to implant into those with macular-induced vision issues.
These stem cells patch up the damage on the macula, a region in the back of the eye home to many of our photoreceptors, a light-sensitive cell that enables us to see detail. People with macular diseases suffer from a failure in this region, causing them to lose the ability to see fine details and eventually become permanently blind. While the progression can be slowed if caught in time, whatever damage already done to the photoreceptors is considered irreversible.
However, the new study has a groundbreaking premise- they are using stem cells to mimic the macula which could restore vision when transplanted into the retina. By now, they have already discovered which stem cells are suitable to be turned into retinal cells and photoreceptors and are working on turning these into a remedial patch.
According to Medical Xpress, Rachael Pearson, who leads the Kings College team, said:

“Our hope is that this study will give us a better understanding of human macular formation, which we can then use to generate structures for transplantation for the treatment of age-related macular degeneration and other macular dystrophies. To be able to give back any vision to someone who has lost it is so important, but it would be particularly significant to improve vision in the macula, as we are trying to do in this project, because that’s the region upon which we are so dependent on for our high acuity vision. This means reading, seeing people’s faces, all of those tasks which we tend to take for granted. It’s so important for independence.”

What Needs to Happen in the Lab Next

Their next steps are to figure out how to get these stem cells-turned-retinal cells to carry out their function independently, like natural retinal cells. This includes organizing themselves and finding the right positions that will enable their integration into the eye, so they can join the system and carry out their function.
The director of research, Dr. Neha Issar-Brown at Fight for Sight, said to Medical Xpress,
“We know from our recent Time to Focus research report that the prevalence of these conditions is on the rise. If successful, this research paves the way for future transplantation research and possibilities and has the potential to transform the lives of countless people with macular disease.”
This could be a game changer for patients with these diseases or who have been told to expect to lose their vision with age. Katie, age 35, was diagnosed with Stargardt disease and is expected to lose her vision with age. She told Medical Xpress,
“My diagnosis has had a huge impact on my life. It’s always at the back of my mind. I look at my little boys and I think: ‘What am I going to miss when they’re older?’ To be suddenly told you have an eye condition but that there’s nothing that can be done about it because it’s incurable is the hardest thing for me. Any research into a cure or treatment for Stargardt disease and other macular conditions gives me hope for the future and hope is what you have to cling on to when you have a progressive sight loss condition like this.”