As many of my long time readers are aware, I fit into the Venn diagram of research scientists and 3D printing enthusiasts. Add in an interest in medical research, and one can see why this latest scientific breakthrough caught my attention this week.

Biomedical researchers have finally been able to 3D print human tissue.

Technically scientists have already produced 3D printed tissue, but there has always been a major obstacle to producing functioning organs. When organs grow naturally, they develop a vascular network that provides blood and nutrients to the cells in the organ. This is vital for keeping the organ alive, and often for critical functions such as oxygenation of the blood or waste removal. When tissue is 3D printed in the lab, it does not contain these arteries and vessels, and therefore cannot be used in a living body.

To motivate research in this area, in 2016 NASA announced a prize of $500,000 US to the first three teams that could produce "thick, metabolically-functional human vascularized organ tissue” in the laboratory. Now two teams have claimed the prize.

The two winning teams are both associated with the Wake Forest Institute for Regenerative Medicine (WFIRM), located  in Winston-Salem. They won first place and second place, while the third place prize of $100,000 US is currently being fought over by two other teams.

Each of the teams were able to demonstrate that their 3D-printed human tissues were capable of perfusion – the process in which an organism provides nutrients to it cells and removes the resulting metabolic waste. They designed a thick tissue through which nutrients and oxygen can flow, produced by using gel-like molds over which the tissue can be grown. This underlying mold is then dissolved leaving the fake blood vessels in their place.

At this point what they are producing is really just a small lump of human tissue, with no functional resemblance to any actual organ. Their sample has a blood flow and can sustain itself with oxygen and then can remove waste materials, but it is incapable of doing anything else. However now that the cells can be sustained, the next step will be for researchers to use this same technology to generate more complicated structures.

Within a few decades we could see human organ transplants completely replaced with 3D printed artificial organs. Not only will this greatly increase the supply for organs and remove the social issues related to organ donation from both living and dead human donors, but it will also eliminate the need for anti-rejection drugs that are necessary to prevent the recipients immune system from destroying the donors organs. In effect, hospitals will be able to clone the patient's own organs for implanting whenever they are needed. Organ transplants will become as simple as blood transfusions.

Of course that is still many years and countless hours of research away, but this week's announcement is an incredible first step towards that ultimate goal.

Congratulations to the two teams and all of their members for this momentous achievement!