TedEd: How to 3D print human tissue

A TedEd by Taneka Jones

There are currently thousands of people waiting for implants of crucial organs like kidneys, hearts, and livers, but not enough donors for all of them. But what if we could create them from scratch? That's what bioprinting, a new branch of regenerative medicine, aims to do. Although we can't create major organs yet, we have already managed to print blood vessels and other circulatory systems. Bioprinting is similar to 3D printing, which prints layers of material on top of each other. Instead of ceramic, plastic, and metals, Bioprinting uses bioink, which is a printable material containing living cells. Most bioinks are something called a hydrogel, which contains the cells, which may be one or more types, in the hydrogel and other chemicals. The most common form of printing is extrusion printing, in which the ink is loaded into a pen and pushed out through a nozzle that is usually 400 microns wide. The tissue is printed onto a surface or a substance that will keep it stabilized until it is ready. The printed tissue will then behave the same way as normal tissue. Researchers have succeeded in producing things like skin, lung tissue, and cartilage, as well as miniature versions of larger organs. But the problem with those is that it is hard to replicate the bodily environment for larger organs. A faulty nozzle could destroy cells, and then there is the challenge of supplying blood and oxygen to the tissue. And this technology opens up many more possibilities, like computerized organs and prolonged life.