A team of researchers from Newcastle University has 3D-printed human corneas for the first time, in what has been described as a potentially game-changing shift for the medical industry.
In a human eye, the cornea is the layer that fits directly over the iris. When damaged or scratched, it can cause serious loss of vision or even cause complete blindless if trachoma, an infectious eye disease, is contracted. Currently, there is a worldwide shortage of replacement corneas, as 10 million people require operations to prevent corneal blindness.
3D-printed corneas, then, have the potential to solve a real issue. The Newcastle University team achieved this first step, which they are calling a "proof of concept," by taking human stem cells from healthy donor corneas and mixing them with alginate and collagen, creating a mix that can be 'bio-printed.'
This solution can then be printed in a 'low-cost' 3D bio-printer. The corneas are printed in a radial fashion, in concentric circles, simulating 'real' corneas. Currently, one cornea takes around 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."
Dr Steve Swioklo, co-author with Professor Che Connon (right). (Image: Newcastle University)
Professor Connon added: "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."