Scientists at Newcastle University in the UK have successfully created the first ever 3D printed corneas using human tissue.
The scientists, led by Professor of Tissue Engineering at Newcastle University, Che Connon, believe that the technique could be used in the future to ensure an unlimited supply of corneas.
This would be significant for people who are waiting for a cornea transplant because there is currently a global shortage. There are 10 million people worldwide requiring surgery to prevent corneal blindness as a result of diseases such as trachoma, an infectious eye disorder. There are also almost 5 million people suffering from total blindness due to corneal scarring caused by burns, lacerations, abrasion or disease.
In their paper published in Experimental Eye Research, the scientists explain how stem cells (human corneal stromal cells) from a healthy donor cornea were mixed together with alginate and collagen to create a solution that could be printed, a ‘bio-ink’.
By 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. According to the scientists, it took less than 10 minutes to print.
“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,” said Prof Connon.
“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,” continued Prof Connon.
According to the scientists, their technique can be used to develop a cornea to match a patient’s unique specifications. In their proof-of-concept research, the dimensions of the printed tissue were originally taken from an actual cornea. By scanning a patient’s eye, they could use the data to rapidly print a cornea which matched the size and shape.
“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,” said Prof Connon.
“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,” concluded Prof Connon.