Gizmodo Science Fair: A Stem Cell Treatment for Severely Damaged Corneas

Scientists at Mass Eye and Ear are winners of the 2025 Gizmodo Science Fair for their research and development of an experimental stem cell therapy for severely, and supposedly permanently, injured corneas.

The question

Can stem cells help repair previously untreatable eye injuries?

The results

In a small trial of 14 patients published this March, the researchers showed it was possible to take stem cells from a person’s healthy eye and use them to safely replenish the surface of their other severely damaged cornea.

18 months after the procedure, nearly all of the patients continued to show at least a partial response to the treatment and saw their vision improve, while two-thirds experienced a complete restoration of their corneal surface. No severe side effects related to the treatment were reported.

Why they did it

When our cornea—the transparent outer layer of the eye—is harmed by injury or infection, doctors often treat it by transplanting healthy corneal tissue from a donor, also known as a corneal graft. But sometimes, an injury is so damaging that it also wipes away the cornea’s limited supply of surface stem cells, also called limbal epithelial cells. Without these cells, people will experience symptoms like itching, pain, whitened corneas, and eventually loss of vision.

The team’s approach harvests corneal stem cells from the person’s healthy eye and grows them in the lab. These cultivated autologous limbal epithelial cells (CALEC) are then packaged onto a cellular tissue graft that’s transplanted to the other eye.

“Corneal stem cell deficiency is really one of the most common causes of blindness worldwide. These stem cells create a healthy corneal epithelial cell layer, and that is compatible with good vision and no pain and just having a comfortable eye when you blink,†project leader Ula Jurkunas, associate director of the Cornea Service at Mass Eye and Ear, told Gizmodo. “And therefore, we developed this kind of stem cell therapy in response to an unmet medical need for stem cell deficiency and corneal blindness.â€

Why they’re a winner

There is no highly effective treatment for the most severe cases of limbal stem cell deficiency, according to Jurkunas. So CALEC could offer hope to many people who otherwise had no options. And since it uses a person’s own adult stem cells, there’s no worry about the body rejecting the transplant or other ethical considerations commonly brought up with using embryonic stem cells.

But more than just that, it’s breaking new ground in the world of stem cell medicine. According to the researchers, this is the first stem cell therapy of its kind in the U.S. to be used in the eye. For decades, scientists have been studying stem cells as a possible treatment for all sorts of irreversible injuries. CALEC and similar therapies could very well become some of the first bona fide examples of this approach working as intended.

What’s next

Jurkunas and her team are now in discussion with the Food and Drug Administration regarding CALEC’s approval, which may require additional data from a larger trial conducted across multiple research sites. They’re also in talks with potential commercial partners to license the therapy and help fund further development, including a new trial if needed.

Outside of that, the team is still working to improve the shelf life and manufacturing of CALEC cells, which will be important to ensuring that the therapy can be shipped over longer distances.

The team

Jurkunas first started working on the research that gave rise to CALEC as a junior scientist in 2006, nearly 20 years ago. And while the team may bring on commercial partners for the final leg of development, CALEC’s current journey from the lab bench to the bedside has notably been made without any pharmaceutical funding. It has required the collaboration of many other researchers, however, including the scientists in Japan who initially helped Jurkunas learn how to better grow stem cells in the lab.

“It’s taken an enormous amount of study research staff. And then there’s the physician collaborators, Reza Dana, Jia Yin, Lynette Johns; they were the main investigators in the [March 2025] study,†Jurkunas said. “And that’s Mass Eye and Ear only. Then we have Boston Children’s Hospital; we have Dana Farber; we have the JAEB Center, which is our [Contract Research Organization] that helped us with data analysis and management and all the things that you have to do to make sure the data is intact.â€

Jurkunas also pointed out that CALEC would have never come to fruition without the federal funding provided by the National Institutes of Health and the National Eye Institute—the same sort of funding that’s now being endangered by the current Trump administration.

“I want to just remind people that the NIH does support medically transformative therapies that are de novo, they’re new,†she said. “We think of them, we work on them, and we develop them.â€

Click here to see all of the winners of the 2025 Gizmodo Science Fair.