Scientists are very excited about new lab experiments allowing them to restore eyesight in blind mice. The researchers used stem cells to give these mice the ability to see. This is the first time that they have been able to produce sight where it didn’t exist.
According to the team involved, they do not know if the same procedure would work in people or not, until human trials are completed. If this works out, then blind people may be able to see again as well.
How Did the Researchers Give Sight to Mice?
Researchers working at the RIKEN Center for Developmental Biology, a large research facility in Japan, collected skin cells from the mice. In the lab, they were then able to induce them to make pluripotent stem cells. They were then able to convert these stem cells into retinal tissue. Finally, they transplanted the retina tissue into mice that had end-stage retinal degeneration.
The mice were then put into a test box with two different chambers. They first trained the mice to move from one chamber to the other, using a beep and a light, in order to avoid receiving an electrical shock. Eventually, the beep was eliminated to see if the mice could detect just the light.
In 40 percent of the mice, who had the procedure was done in just one eye, the mice responded to the light. In 45 percent of the mice, where both eyes were transplanted, the mice could see as well. That’s a high percentage for a trial to restore eyesight with no previous groundwork to rely on.
The researchers hope that over time, eye-brain connection techniques can be improved to make these percentages even higher.
Can the Same Thing Happen in Humans?
Lead researcher Dr. Michiko Mandai says:
From a clinical point of view, although we think that these results are very promising, human eyes may have a different environment from mice.
He adds that without human studies, there is no way to know if human eyes would accept such retina transplants and then make connections with the brain. In his opinion, those answers can only be found when human tests are done.
According to the scientists, it would be very exciting if it did work, because this would restore eyesight and light sensitivity to those currently struggling with blindness. They believe that it would also mean those affected could see large objects.
If successful, this would be particularly great news for people with retinal degeneration. While there are several different types of this disease, everyone suffering from it experiences damage to photoreceptor cells (which allow them to sense light). Depending on the stage of degeneration, the person may see a blurred image, distorted, or see no image at all.
The most common type of retinal degeneration is age-related macular degeneration. This disease that is usually seen in people over 50 slowly destroys the ability to see straight ahead. It can eventually make a person go totally blind.
Caucasians are more likely to experience this disease than people from other ethnic groups. Scientists know that over 20 genes that can be passed down can cause age-related macular degeneration.
Therefore, people are at a higher risk if one or both parents have the disease. Those who smoke or do not exercise are also more likely to develop this disease. Eating a well-balanced diet can also help prevent it.
For the first time, scientists have been able to grow retina tissue in the lab from stem cell. They were also able to transplant it into mice and restore eyesight at least partially (in regards to perceiving light). Scientists are still not sure if the same will work in humans or not without completing a human trial.
If the procedure works for human subjects, people with retinal degeneration will be able to see again. This would be great news for everyone suffering from age-related macular degeneration.
Image source: here.