A 3D-printed artificial cornea made of decellularised corneal stroma and stem cells may eventually replace the use of donated corneas in eye surgery.
A group of researchers at the Pohang University of Science & Technology and the Kyungpook National University School of Medicine in South Korea worked together to 3D print an artificial cornea using tissue-derived bioink. Their research has been published in Biofabrication.
Because the 3D-printed cornea is composed of materials deriving from corneal tissue it is biocompatible, with 3D cell printing technology recapitulating the corneal microenvironment so that its transparency is similar to the human cornea.
There are roughly 2,000 patients awaiting cornea donation in South Korea, who wait an average of six years for surgery. While artificial corneas are available for patients who cannot find a suitable donor, those currently on the market are made up of recombinant collagen or chemical substances such as synthetic polymer. This means they can often resist full incorporation into the eye or are not transparent after the cornea implant.
This is because the cornea is organised in a lattice pattern of collagen fibrils, which directly impacts the transparency of the cornea. Many researchers have tried to replicate this structure via a synthetic artificial cornea but have struggled to do so.
The researchers at Pohang and Kyungpook were able to solve this problem through the shear stress generated by the frictional force of the 3D printing process when the bioink passed through the nozzle. Regulating the shear stress to control the pattern of the collagen fibrils manufactured the necessary corneal lattice pattern, demonstrating that corneal stroma-derived decellularised extracellular matrix bioink was biocompatible and could be transplanted into a human eye.
The research team also observed that the collagen fibrils remodelled along with the printing path create a lattice pattern similar to the structure of native human cornea after four weeks in vivo.
A 3D-printed artificial cornea derived from real corneal tissue could help to bypass both the difficulties of finding a donor match and the complications associated with synthetic corneas for patients with cataracts and other ocular complications.
Pohang University of Science & Technology professor Jinah Jang said: “The suggested strategy can achieve the criteria for both transparency and safety of engineered cornea stroma. We believe it will give hope to many patients suffering from cornea-related diseases.”