Countless people are waiting for an implant to be made available to them. But what if, instead of waiting for a donor to die, one day we could grow our own organs? Six years after the announcement of the NASA “Vascular Tissue Challenge” competition, which was supposed to advance research into artificial organs, the US space agency has now chosen two winning teams. The challenge was to create thick, blood vessel-riddled human organ tissue that could survive for 30 days.
From the printer
The two teams, named Winston and WFIRM, both from the Wake Forest Institute for Regenerative Medicine, used different 3D printing techniques to create laboratory-grown liver tissue that meets all of NASA’s requirements and maintains its function. “We took two different approaches because when you look at tissues and vessels, there are two essential things the body does,” explains Anthony Atala, team leader at WFIRM and director of the institute.
The two approaches differ in the way in which vascularization – i.e. the formation of blood vessels in the body – is achieved. One uses tubular structures, the other sponge-like tissue structures to supply the cell with nutrients and to transport pollutants away. According to Atala, the challenge represents a milestone in bioengineering as the liver, the body’s largest internal organ, is one of the most complex tissues to replicate because of the many functions it performs.
“When the competition was advertised six years ago, we knew we wanted to solve this problem on our own,” says Atala. In addition to advancing regenerative medicine and making it easier to make artificial organs for people who need a transplant, the project could one day also help astronauts on future space missions.
Work in space
The concept of tissue engineering has been around for more than 20 years, says Laura Niklason, professor of anesthesia and biomedical engineering at Yale, but the growing interest in space-based experimentation is beginning to change the field. “Especially as our planet is now considering private and commercial space travel, the biological effects of low gravity become increasingly important – and this technique is a great tool to help understand.”
But the winning teams still have to overcome one of the biggest hurdles in tissue engineering: “Getting the artificial organs to survive and maintain their function over a longer period of time is a real challenge,” says Andrea O’Connor, Head of Biomedical Engineering the University of Melbourne, which describes the NASA-funded projects and similar projects as “ambitious”. Armed with a cash prize of US $ 300,000, the winning team – Winston – will soon have the chance to send their research to the International Space Station, where similar research has already taken place.
In 2019, astronaut Christina Koch activated the BioFabrication Facility (BFF), created by the Greenville, Indiana-based space research company Techshot, to print organic tissue in zero gravity. This research project has goals similar to NASA’s Vascular Tissue Challenge, says Eugene Boland, chief scientist at Techshot – only that instead of 3D printing liver tissue, transplantable heart tissue will be made sometime in the next 10 years.
The work on the ISS is different
What is the difference between the pressure of organs and tissues on earth and in space? Boland describes the difference between the processes by comparing the mechanics of printing with modeling clay with that of printing with honey. This year, the BFF is facing an upgrade – one that, according to Rich Boling, Vice President of Corporate Advancement at Techshot, will make the potentially life-saving technology more effective for future commercialization both in space and on Earth. Over the next few months, this upgrade will include the ability to print with blunt needles – the same type used on Earth to print such organs.
“The project has always been largely about the earth. We always had the feeling that we were developing it for problems such as the lack of organ donors,” said Boling. Techshot also has a vision of one day using artificial tissue and organs to treat diseases and even congenital genetic defects. But this is also useful for space travel.
Artificial organs and human tissue are just two of many resources that could be in demand in future long-term space missions. Techshot is soon planning to take part in NASA’s “Deep Space Food Challenge”, which aims to develop sustainable food for longer manned missions. The company believes the same 3D printing techniques used in biomedical engineering could also be useful in creating a source of food. Conclusion: Even if it will take a while before astronauts can implant each other artificial tissue or consume their favorite bioburger, the 3D bioprint opens up a lot of possibilities.