Biosynthetic corneas restore vision to humans

By Ben Coxworth

 

Dr. May Griffith displays a biosynthetic cornea that can be implanted into the eye to repair damage and restore sight

A study made public this Wednesday has shown that biosynthetic corneas can and do restore eyesight in humans. Researchers from the Ottawa Hospital Research Institute (OHRI) and the University of Ottawa in Canada, along with Linköping University in Sweden, conducted a clinical trial using ten Swedish patients with advanced keratoconus or central corneal scarring. Each patient had the damaged corneal tissue in one eye surgically replaced with a biosynthetic cornea made from synthetically cross-linked recombinant human collagen. After two years, six of the patients’ vision had improved. After being fitted with contact lenses, their vision was comparable to that of someone who had received a real human cornea transplant.

"This study is important because it is the first to show that an artificially fabricated cornea can integrate with the human eye and stimulate regeneration," said Dr. May Griffith, who holds positions at OHRI, the University of Ottawa and Linköping. "With further research, this approach could help restore sight to millions of people who are waiting for a donated human cornea for transplantation."

Over a decade ago, Dr. Griffith started developing biosynthetic corneas in Ottawa, using laboratory-produced human collagen molded into the shape of a cornea – collagen is what “real” corneas are made from, too. After extensive testing, she began her collaboration with Dr. Per Fagerholm, an eye surgeon at Linköping, to provide the first-in-human experience with biosynthetic cornea implantation.

The patients in the trial didn’t experience any rejection reaction or require long-term immune suppression, which are complications that sometimes occur when human tissue is transplanted. During the two-year follow-up period, the researchers observed nerves and cells from the patients’ own corneal material growing into the implants, ultimately resulting in normal-looking “regenerated” corneas. The biosynthetic corneas also became sensitive to touch, and stimulated tear production to keep the eye oxygenated.

"We are very encouraged by these results and by the great potential of biosynthetic corneas," said Dr. Fagerholm. "Further biomaterial enhancements and modifications to the surgical technique are ongoing, and new studies are being planned that will extend the use of the biosynthetic cornea to a wider range of sight-threatening conditions requiring transplantation."

The research was published in the current issue of the journal Science Translational Medicine.