Text | Xu Rui
Cornea made of pig collagen Image source: THOR BALKHED/Linkoping University
More than 12 million people worldwide suffer from corneal blindness, which is when the transparent protective outer layer of the eye changes due to injury or disease. Blindness can result when blurred or deformed. However, the treatment of corneal blindness is very difficult. First, there is a shortage of donors. Currently, only 1 in 70 people who need corneal transplants can have a matching donor cornea. Second, in many low-income countries, the high cost of surgery makes people Treatment is difficult to obtain.
To this end, scientists have been looking for transplants that can replace the human cornea.
Recently, researchers from Linköping University in Sweden and LinkoCare Life Sciences successfully restored sight to people who were blind or visually impaired by extracting artificial cornea made from porcine collagen. Two years after the operation, the patient had no serious complications. reports of symptoms or side effects. Relevant research was published in Nature Biotechnology on August 11.
Mehrdad Rafat of Linköping University and colleagues created a flexible and elastic contact lens-like artificial cornea by extracting and purifying collagen from pig skin. After successful trials, the team began testing the artificial corneas on volunteers.
The 20 volunteers who participated in the test all suffered from keratoconus (the cornea thins and bulges outward from the center of the eye). Among them, 14 were completely blind and 6 had severely impaired vision. After receiving artificial corneal transplantation, everyone's vision improved, and the vision of three blind patients returned to normal levels after surgery.
"The day one of the patients had an artificial cornea implanted for the first time, I stayed up all night, waiting for the surgeon to tell me the progress of the operation." Rafat recalled, when we learned that the patient's vision had recovered, we were very surprised. The effect of the operation was better than Expected much better.
Collagen is a structural protein, and artificial corneas made from porcine collagen are not rejected by the immune system compared to human donor corneas. Patients who have been transplanted with a human donor cornea usually need to take medication for several years to avoid rejection, but the patient who participated in the corneal transplant only needed to use immunosuppressive eye drops for 8 weeks.
But some experts pointed out that this new artificial cornea may not be as groundbreaking as it initially seems because "it does not cure anyone who cannot be cured by existing technologies."
In this regard, Neil Lagali from Linköping University said that the research results will help develop a biomaterial that meets all standards for human implants and can be mass-produced and stored for up to two years, thereby benefiting more people with vision problems. people. "This could help us address the shortage of donated corneas and gain access to other treatments for eye disease."
At this time, Rafat is not sure of the final cost of the surgery, but he thinks it should be more expensive than the tens of thousands of dollars it would cost in the United States. Somatic corneal transplantation is more affordable. However, further clinical trials are needed before porcine protein artificial corneas can be widely used.
related paper information:
https://doi.org/10.1038/s41587-022-01408-w
