Using 3D printers to create tissue is nothing new. It started with printing of skin and progressed with printing jaws and windpipes. In the labs, researchers are working on printing more complex tissues and organs. Bladder and liver have attracted the attention of researchers as well as the heart.
The 3D printing of tissues makes use of cells harvested from the patient that are cultured to multiply until there is a sufficient number of them. When cells are cultured they multiply since they are not constrained by the presence of other cells, each one in “floating” on its own. They are used as ink by the printer.
The problem in 3D printing organs is that one needs to print different types of tissues as well as create structures including blood vessels. For 3D printing of hard structures, like bones and trachea, the approach is based on using a scaffold upon which the cells are layered. This is not possible for soft organs, like a bladder or the heart.
To create these organs a different approach is needed.
Researchers at the Tel Aviv University, Israel, have managed to print a (miniature) heart using human cells, collagen and biological molecules. They have used a hydrogel to deposit the “bio-ink” with the 3D printer, growing the heart inside the gel.
The cells in this miniature heart, the size of the heart of a mouse, contract as they should but are not contracting in a synchronous way so they would be ineffective in pumping blood.
The researchers concede that this is a tiny step and it will take at least ten more years to be able creating a fully functional heart that could be used for a transplant. At the same time, (watch the clip) they are sure that this is the way to go and that in the coming decade organ printing will meet the demand of organ transplant.