Blind People Gain 20/20 Vision With Cornea Made From Pig Collagen
By Mikelle Leow, 12 Aug 2022
Patients who were legally blind or visually impaired regained some or all of their vision after receiving a bioengineered cornea crafted from the protein of pig skin.
The 20 patients, live in Iran and India, were diagnosed with keratoconus, a condition where the eye’s protective outer layer gradually gets thinner and bulges outward (as depicted in the image above). The condition affects 50 to 200 out of 100,000 people.
Amazingly, two years after getting the implant, 14 of the patients got some or all of their vision back. Three others got perfect 20/20 vision after healing.
So far, none of their bodies have rejected the implants nor suffered inflammation or scarring.
The implant, developed by researchers at the Linköping University in Sweden, is made from pig tissue that has been dissolved into a collagen solution. This substance is turned into a hydrogel resembling the human cornea.
The synthetic cornea was inserted into the patients’ eyes through an incision made into their corneas. The addition thickened the corneas and restored their shape.
Two years after observing the patients’ recovery, the team has detailed its findings in the Nature Biotechnology journal.
Neil Lagali, a professor of experimental ophthalmology at the institute and co-author of the study, tells NBC News that the creators were “surprised with the degree of vision improvement.”
Lasting only half an hour, the procedure was also speedier than the conventional cornea transplants, which would typically take a few hours.
All told, not every patient developed normal sight. The 12 Iranian participants had an average visual acuity of 20/58 when wearing glasses, which is lower than the 20/40 standards of functional vision with glasses.
Further, an experimental procedure such as this comes with risks. There’s a chance that the collagen, a foreign molecule, might bring forth an immune response. To counter this, the team got the patients to use immunosuppressive eyedrops for eight weeks—something that patients who have gotten traditional cornea transplants from human tissue would have been administered at larger dosages and for a longer period of time.
Dr Marian Macsai calls the innovation “revolutionary” as it could make corneas more readily available for patients who may need them.
Corneal blindness affects 12 million people worldwide, and they’ll need to wait for a human donor to die before receiving a transplant. Pigskin collagen happens to be a byproduct of the food industry which often gets discarded, making it extremely accessible.
That means even patients in areas with limited medical resources—the very places with the highest blindness rates—could be able to get corneal transplants too, notes Lagali.
Moving forward, the team hopes to expand the study to more than 100 patients, as well as gain regulatory approval for the implant by the Food and Drug Administration and other authorities.
[via New Scientist and NBC News, cover photo 209464013 © Ukrainian photographer Zarina Lukash | Dreamstime.com]