Possible solution to the shortage of corneas donated

Tissue engineers at Newcastle University have developed a biological system that creates cell structures of tissues which can change shape over time into a desired form. The so-called “4D tissue” building technique creates self curving synthetic cornea, formed from corneal stem cells condensed into a collagen gel which was cast into two concentric flat circles. These circles were then treated with serum containing peptide amphiphile molecules which turned the cells into biological actuators, which over time pulled the flat structure into the desired three-dimensional shape.
Professor Che Connon, a professor of tissue engineering at Newcastle University, said: “Currently there is a shortage of donated corneas which has worsened in recent years, as they cannot be used from anyone who has had laser eye surgery so we need to explore alternatives such as these self-curving corneas. The cells are triggered into forming a complex 3D structure, but as this requires time to occur, the fourth dimension in this equation, we have labelled them 4D structures. The technology and understanding we have developed holds enormous potential as these corneas show that engineered tissue shape can be controlled by cell actuators. This may lead us to imagine a future where such an approach can be combined with key-hole surgery enabling a surgeon to implant tissue in one shape which then develops into a more complex, functional shape within the body, driven by the behaviour of the cells themselves. Because all the process was orchestrated by the cells themselves, we can envision them as bio-machines remodelling these structures from the inside.”
Martina Miotto, lead author of the paper, said: “This is a cutting-edge example of the strict relationship between form and function. The research also showed that the biomechanical and bio-functional properties of these 4D structures reproduced those of the native tissue, with undifferentiated corneal limbal epithelial stem cells located in the softer limbus and the differentiated epithelium spanning the stiffer centre of the anterior cornea.”