STEM Cell Treatment for Vision Loss

Researchers at Japan’s Osaka University recently discovered a treatment for impaired vision using stem cells. **Courtesy of U.S. Food and Drug Administration – Stem Cell Research via Wikimedia Commons**

Stem cells are a unique type of cells that have special properties, allowing them to “develop into many different types of cells in the body.” While originally unspecialized, they have the ability to become specialized — in other words, take on a unique function in the body — and replace dying cells in that area, whether it be the brain, the blood, or the eye.

Recently, scientists have been making advances in stem cell treatments. For example, a research team in Japan was able to substantially improve the vision of three people with “severely impaired vision” using stem cell treatment. The improvements lasted for more than a year. However, for the fourth individual who received this treatment, the improvement in vision did not last. This treatment specifically involved the use of reprogrammed stem cells which was founded by Shinya Yamanaka in his Nobel prize-winning work.

First, scientists need to turn off the specific gene in the cell that allows it to “identify as a specific type of cell” and turn on the specific gene that codes for the cell to become a stem cell. Eventually, given their surroundings, the cells will “grow, divide, and differentiate into various cell types.”

In a healthy eye, the outside of the cornea is surrounded by stem cells, but when participants experience a condition called limbal stem cell deficiency (LSCD), the stem cells in their cornea are deficient, leading to eventual blindness. This disease is normally caused by “trauma to the eye or … autoimmune or genetic diseases.” In order to combat the effects of this progressive disease, Dr. Kohji Nishida and his colleagues from a university in Japan injected stem cells from a healthy donor into the cornea of four individuals with LSCD. Two years after this procedure, it was noted that there were no detrimental side effects to the individuals that received the treatment and, rather, they all showed “immediate improvements” with the improvements being stable in three out of the four individuals. Overall, while there were significant improvements in the participants’ vision the reasoning for the results was still murky, due to the impact of removed scar tissue or their own population of cells affecting the improvement of the cornea. Whether the results were due to the effect of stem cells or not, knowing the impact that stem cells have on diseases such as LSCD could impact the treatment of other conditions in the future.