Using lab-created tissue to heal or replace damaged organs is one of the great visions for the future of medicine. Synthetic materials could be suitable as scaffolding for tissue because, unlike natural tissues, they remain stable in the organism long enough for the body to form new natural structures. A fundamental requirement for functional tissue is that blood vessels must be able to grow in them and connect to the organism’s vascular system, so that the tissue is properly supplied with oxygen and nutrients. However, until now, almost nothing has been known about which material properties promote the growth of blood vessels. A team headed by biomedical engineer Dr Britta Trappmann from the Max Planck Institute for Molecular Biomedicine in Münster, Germany, has developed a cell culture system in which, for the first time, a functional blood vessel system is able to grow within a framework made of synthetic materials.