The scientists from the Newcastle University, UK, managed to print the human cornea with the “bio-ink” from stem cells for the first time on a 3D printer. This means that the new technology can be used to unrestricted creation of corneas for transplantation in the near future. The results of the work were published on May 30, 2018 in Experimental Eye Research.
The cornea is a outermost layer of the human eye, which protects the inner layers from penetration of bacteria and damage. The cornea also plays an important role in focusing vision.
Currently, about 10 million people all over the world need a corneal transplant surgery to prevent blindness from infectious eye diseases, such as trachoma, for example.
Almost 5 million people suffer total blindness due to corneal scarring as a result of burns, lacerations, abrasion or various diseases. However, donor material for transplantation is sorely lacking.
In the new study, scientists created a bio-ink from alginate and collagen with the addition of stem cells (corneal stromal cells), obtained from a healthy donor cornea. Using a simple low-cost 3D bio-printer, the bio-ink was successfully extruded in concentric circles to form the shape of a human cornea. It took less than 10 minutes to print.
Che Connon, Professor of Tissue Engineering at Newcastle University, who led the work, said: “Many teams across the world have been chasing the ideal bio-ink to make this process feasible. Our unique gel – a combination of alginate and collagen – keeps the stem cells alive whilst producing a material which is stiff enough to hold its shape but soft enough to be squeezed out the nozzle of a 3D printer.
This builds upon our previous work in which we kept cells alive for weeks at room temperature within a similar hydrogel. Now we have a ready to use bio-ink containing stem cells allowing users to start printing tissues without having to worry about growing the cells separately”.
Dr Neil Ebenezer, director of research, policy and innovation at Fight for Sight (nonprofit organization in the United States which funds medical research in vision and ophthalmology), said: “We are delighted at the success of researchers at Newcastle University in developing 3D printing of corneas using human tissue.
This research highlights the significant progress that has been made in this area and this study is important in bringing us one step closer to reducing the need for donor corneas, which would positively impact some patients living with sight loss. However, it is important to note that this is still years away from potentially being available to patients and it is still vitally important that people continue to donate corneal tissue for transplant”.
Researchers from the Institute of Genetic Medicine at the University of Newcastle demonstrated that they are able to create a cornea in accordance with the unique characteristics of a person. By scanning a patient’s eye, they could use the data to rapidly print a cornea which matched the size and shape.
Professor Connon added: “Our 3D printed corneas will now have to undergo further testing and it will be several years before we could be in the position where we are using them for transplants. However, what we have shown is that it is feasible to print corneas using coordinates taken from a patient eye and that this approach has potential to combat the world-wide shortage.”