First 3D printed human corneas produced by Newcastle team

(Credit: Newcastle University)

The team create a bio-ink using human corneal stromal cells from a healthy donor. These were mixed with alginate and collagen to create a solution that could be printed. Using a low-cost bio-printer, the bio-ink was extruded in concentric circles to create a shape that mimics the human cornea, a process that took just 10 minutes.

Once printed, the corneal stem cells – also known as keratocytes - were found to grow. According to the study, published in Experimental Eye Research, the keratocytes exhibited high cell viability both at day one post-printing (>90 per cent) and at day 7 (83 per cent). The breakthrough could lay the foundations for lab-grown corneas to be made available for millions of people around the world at risk from corneal blindness.

"Many teams across the world have been chasing the ideal bio-ink to make this process feasible,” said project lead Che Connon, Professor of Tissue Engineering at Newcastle University. "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.