For people with severely damaged corneas, a cornea transplant is the common solution. But due to the long wait—six or more years on average—for a cornea donation, scientists are looking to develop an artificial cornea. However, existing artificial corneas use recombinant collagen or are made of chemical substances such as a synthetic polymer. They do not incorporate well with the eye, or are not transparent after implantation.
But a solution may be on the way, thanks to the innovative use of 3D printing. Researchers Professor of Mechanical Engineering Dong-Woo Cho, Professor of Creative IT Convergence Engineering Jinah Jang, and Ms. Hyeonji Kim from POSTECH, collaborated with Professor of Ophthalmology at Kyungpook National University School of Medicine Hong Kyun Kim, to 3D print an artificial cornea. The cornea is printed using a bioink comprising decellularized corneal stroma and stem cells. The cornea is thus biocompatible and provides transparency similar to the human cornea.
The scientists recently published their study in Biofabrication.
The cornea is the thin outermost layer that covers the pupil and protects the eye from the external environment. Up to now, researchers have been unable to use synthetic biocompatible materials to develop an artificial cornea because of different cornea-related properties. The materials used in existing studies have limited microstructures to penetrate the light.
The human cornea is organized in a lattice pattern of collagen fibrils. To overcome the limitations of existing cornea transplant technology, the researchers used shear stress generated in the 3D printing to manufacture the corneal lattice pattern. They demonstrated that using a corneal stroma-derived, decellularized extracellular matrix bioink produced a biocompatible cornea.
The research team also observed that the collagen fibrils remodeled along with the 3D printing path created a lattice pattern similar to the structure of a native human cornea after four weeks in vivo.
“The suggested strategy can achieve the criteria for both transparency and safety of engineered cornea stroma,” says Professor Jang. “We believe it will give hope to many patients suffered from cornea-related diseases.”