Light-activated 3D printing produces branching blood vessels

A novel approach to 3-D printing has helped nanoengineers at the University of California San Diego to produce lifelike, functional networks of synthetic blood vessels that, in animal trials, have successfully integrated into living subjects. The team believes that this could be a first step towards a long-desired goal of being able to print functional organs and other regenerative therapies.

Previous work on printing blood vessels has tended to focus on printing very simple structures, such as a single vessel – effectively a tube. The San Diego research, in the Nanobiomaterials, Bioprinting, and Tissue Engineering Laboratory directed by Prof Shaochen Chen, has resulted in a network featuring branching vessels that become successively smaller, similar to those found in living tissue where they supply oxygen and nutrients and remove waste from cells.

The technique works by creating a 3D computer model of the desired structure. The computer then transfers two-dimensional snapshots of this structure from different angles to a series of motorised mirrors, which project ultraviolet light following the shape of these snapshots until onto a solution containing live cells and UV-sensitive polymers. The polymer solidifies layer by layer, trapping the cells in such a way that they can continue to grow into the shape of the structure.