Nov 17, 2015

Restoring Vision with Stem Cells

Fighting Blindness Canada-funded researchers have succeeded in producing large amounts of human photoreceptors from stem cells. New findings by Dr. Gilbert Bernier from the University of Montreal fuel our hope in the potential of stem cells to treat vision loss.

Dr. Bernier’s research is making the news because his team has developed a highly effective technique for producing light sensitive retina cells (cone photoreceptors) from embryonic stem cells. “Our method has the capacity to differentiate 80% of the stem cells into pure cones,” Professor Bernier explained. “Within 45 days, the cones that we allowed to grow spontaneously formed organised retinal tissue… This has never been achieved before.”

We were excited to learn about this news at our recent Montreal Vision Quest event, thanks to Dr. Bernier’s students, Andrea Barabino and Anthony Flamier, who presented the findings in an incredible poster.

Thanks to this discovery, any laboratory in the world can now create photoreceptors,

Dr. Bernier explained. “To date, it has been difficult to obtain great quantities of human cones [photoreceptors].” His discovery offers a way to overcome this problem, offering hope that treatments may be developed for currently non-curable degenerative diseases, like Stargardt disease, retinitis pigmentosa and age-related macular degeneration (AMD). “Researchers have been trying to achieve this kind of trial for years,” said Dr. Bernier. “Thanks to our simple and effective approach, any laboratory in the world will now be able to create masses of photoreceptors… this means, in theory, that we will eventually be able to treat countless patients.”

The findings are particularly significant in the light of improving life expectancy and the associated increase in cases of AMD, which is the greatest cause of blindness amongst people over the age of 50 and affects millions of people worldwide. And as we age, it is more and more difficult to avoid. Amongst people over 80, this accelerated aging of the retina affects nearly one in four. People with AMD gradually lose their perception of colours and details to the point that they can no longer read, write, watch television or even recognize a face.

Big Return on Investment – 18 Years in the Making

Dr. Bernier has been working on this project for 18 years. The idea first came to him in 1997, just after he completed his Phd. Dr. Bernier recalled: “During my post-doc at the Max-Planck Institute in Germany, I developed the idea that there was a natural molecule that must exist and be capable of forcing embryonic stem cells into becoming cones.” Indeed, bioinformatic analysis led him to predict the existence of a mysterious protein: COCO, a “recombinational” human molecule that is normally expressed within photoreceptors during their development.

In 2001, he launched his laboratory at Maisonneuve-Rosemont Hospital and immediately isolated the molecule. But it took several years of research, supported by Fighting Blindness Canada, to demystify the molecular pathways involved in the photoreceptor’s development mechanism. His latest research shows that in order to create cones, COCO can systematically block all the signalling pathways leading to the differentiation of the other retinal cells in the eye. It’s by uncovering this molecular process that Bernier was able to produce photoreceptors. More specifically, he has produced S-cones, which are photoreceptor prototypes that are found in the most primitive organisms.

Beyond the clinical applications, Dr. Bernier’s findings pave the way for modelling a variety of human retinal degenerative diseases and offer the possibility of testing potential therapies using the patient’s own tissues. Thank you, Fighting Blindness Canada donors, for enabling us to make a long-term investment in Dr. Bernier’s research program. Research takes time, but the rewards will be life changing.

About this study:

Shufeng Zhou, Anthony Flamier, Mohamed Abdouh, Nicolas Tétreault, Andrea Barabino, Shashi Wadhwa and Gilbert Bernier published “Differentiation of human embryonic stem cells into cone photoreceptors through simultaneous inhibition of BMP, TGFβ and Wnt signaling” in Development on October 6, 2015. DOI: 10.1242/dev.125385