A team of South Korean researchers has achieved an important breakthrough in regenerative medicine: they have created a human cornea in the laboratory using 3D printing. He hopes this discovery will help restore sight to millions of people in the future. However, the method would not work in every situation, but only if the vision problems were caused by a corneal condition.
In order to achieve success, the researchers from Pohang University of Science and Technology and Kyungpook National University they used a “biological material” made from the structure of a donor cornea and combined it with stem cells. This mixture – also called bioink -it was then “printed” layer by layer, until an artificial cornea resulted. The study was published in the scientific journal Biofabrication.
Why discovery is important
The cornea is the transparent part of the front of the eye that allows light to pass through. To function properly, it must be perfectly clear.
The problem is that its internal structure is made up of very fine collagen fibers arranged in an orderly pattern. If this structure breaks down, the cornea loses its transparency and vision is impaired.
So far, attempts to create artificial corneas have not been able to perfectly reproduce this structure.
But the South Korean researchers discovered during printing that they could control the friction that occurs as the material passes through the printer’s nozzle in a way that guided the collagen fibrils to organize into the same orderly network found in a healthy human cornea.
Test results
In laboratory and animal tests, the results were promising:
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over 90% of the cells remained viable after printing, indicating that the tissue not only survives the printing process but remains biologically active.
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the tissue integrated into the eye in about four weeks
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there have been early signs that the nerves are starting to recover
- the tissue maintained optical transparency and flexibility, two properties critical to visual function.
All of these are essential for normal eye function.
What the discovery means for patients
Globally, many people have serious corneal problems, and some of them can be treated by transplantation. The problem is that there are not enough donor corneas for all patients.
It is estimated that there is only one cornea available for about 70 people who need a transplant, and millions of people suffer from vision loss from causes that can be treated by intervention. In some regions, including South Korea, waiting lists can reach years.
An important aspect of the technology is that it does not completely eliminate the need for donors, but rather optimizes their use. Donated tissue is used as the base material, but it can be processed and multiplied to produce more implants. In some scenarios, a single donated cornea could be used to generate tens or even hundreds of bioprinted implants.
The road from the laboratory to everyday practice
Teams of scientists are currently working to expand the research to clinical trials in humans, following the results obtained in the preclinical phases.
Although the technology is not yet available for widespread use – and could be years away – the results are seen as an important step towards the development of ‘on demand’ bioprinted corneal implants.
