New Master Control Gene Provides Key Insights into Restoring Vision

October 31st, 2017 by Dr. Chad Andrews

With support from the FFB community, Dr. Michel Cayouette’s research is advancing the field of stem cell therapy in extraordinary ways; it is doing so by illuminating how stem cells are produced, how they turn into other cells, and the role they play in the overall biology of the human eye.

Dr. Cayouette’s ultimate goal? The transplantation of new cells into individuals living with vision loss, leading, of course, to the restoration of vision. Stem cells are the key to this, according to Dr. Cayouette. The work that he and his team have advanced has laid strong foundations in this field, and with your continued support they can realize their vision of a world without blindness.

Stem cells have emerged as a major force in the fight to end blindness, largely because they have the unique ability to turn into other kinds of cells. As a result, they have incredible applications, including the potential to transform into the cells that are lost in many inherited retinal diseases: namely, the photoreceptors that convert light into the brain-signals that give us vision.

But as many researchers have discovered, we cannot simply deposit stem cells in the eye and expect them to replace missing cells. Researchers—including Dr. Cayouette and his team—are able to turn stem cells into photoreceptors in a controlled environment in vitro (in a dish), but transplanting them into the eye and having them function properly is the next challenge.

This is where the true value of Dr. Cayouette’s research lies. In order to successfully transplant stem cells into the human eye, we must first understand the processes that control how stem cells function. If we fail to do so, we will not have a clear idea of what happens to a cell when it is placed in an uncontrolled biological environment—in vivo (in living tissue) instead of in vitro. It would be like introducing a new organism into an ecosystem without understanding the potential effects: the organism could die off, it could overwhelm other forms of life, and so forth. The results could be catastrophic.

Supported by a joint funding partnership between the FFB and the Canadian government, the most recent breakthrough in Dr. Cayouette’s lab is not only exciting but ground-breaking. It involves the discovery of a specialized gene, one that tells us a lot about stem cells in the human eye. Dr. Cayouette is going to announce the name of the gene in an upcoming publication, but for now we know that it is in the “master regulator” category. These kinds of genes are unique in that they control how certain cells develop; in the case of Dr. Cayouette’s gene, it tells retinal stem cells to turn into either cone or rod photoreceptors (cones are responsible for central vision, rods for peripheral).

If he can find a way to harness this gene’s function, he will be able to more effectively control the development of stem cells into photoreceptors—and not just in a petri dish, but in a live, biological environment. It is useful in this case to think of the eye in metaphorical terms as a kind of production line, including several intricate pieces such as human workers, machinery, and so forth. If you want to change what the factory produces—in the case of the eye, the end-product is vision—it is best to talk to the factory supervisor, the individual who oversees and controls all aspects of the system. This approach is more effective than trying to communicate with each production worker individually.

Dr. Cayouette’s master regulator gene has the potential to fill this role; rather than ensuring that each cell in the eye is functioning properly, this important gene could oversee the entire process, could ensure, for example, that stem cells are doing what is necessary to compensate for lost photoreceptors.

In the assembly line of the eye, Dr. Cayouette’s breakthrough can enable us to better control stem cells in a biological environment and more effectively manage their role in the production of sight. With continued support from the FFB community, Dr. Cayouette and his team will design a way to transplant functional photoreceptors into human eyes. The end-point of their work is nothing less than the restoration of vision in individuals living with vision loss. An end to blindness. That is the team’s aspiration and mission—with your support they can make it happen.