Bioprinting in Space Could Finally Allow the Synthesis of Complex Tissues

Recently, the medical technology company Auxilium Biotechnologies announced that it conducted a test aboard NASA’s SpaceX CRS-34 mission, attempting all-new forms of bioprinting in space. It successfully printed samples of kidney, liver, and cartilage cells, along with several neural implants, demonstrating the real potential of microgravity in orbit to advance medicine.

Bioprinting full tissues has long been a holy grail for medical science, and while just about any individual cell type is easy enough to grow, producing finished tissues from those cells has always proved difficult due to the specific three-dimensional structure that defines them. Pair that with the fact that they are often made up of multiple cell types laced together in complex ways, and you have a very difficult problem to solve.

So, in 2024, Auxilium sent its 3D bioprinter up to the International Space Station to conduct experiments in an environment where “down” goes out the window. It’s an unintuitive approach, since regular human bodies form on the surface of the Earth, not in free fall; it was entirely possible that human developmental processes would not work in space at all.

Working neural implants, 3D printed in space.
Credit: Auxilium Biotechnologies

However, human biology is highly adaptable to space, and this seems to hold true all the way down to the cellular level. It turns out that cells can grow and adhere to one another quite well in orbit, and the ability to work with weightless samples from any angle makes certain types of physical organization much easier to achieve.

The research began by printing biocompatible neural implants for surgical delivery and lacing them with specific drugs. Gravity causes the distribution of the drug-containing particles to become uneven, causing them to sink to the bottom, so the implant will not be able to provide continuous access to the drug to all necessary nerves. Freefall fixes this problem.

There are some simple organs that can be grown on particular frameworks or substrates, like growing a bladder around a balloon. There have also been attempts to build more complex three-dimensional scaffolds for growing things like hearts, but nothing implantable just yet.

In microgravity, the problem of three-dimensional organization becomes a lot easier to deal with.

NASA astronaut Jasmin Moghbeli swaps components inside a separate bioprinting experiment.
Credit: NASA

After that, the team turned to growing the first-ever liver and kidney cells in space. We’ll have to wait for more detailed results and follow-up studies, but the team is convinced that the technique can create real therapies in the future.

The problem is that genetic medical technologies and grown organs are already expensive, as are transplants, for that matter. If the cost of a space launch were between a patient and getting a new liver, only a very tiny fraction of people could afford it.

We could imagine a future Moon base helping with this, allowing doctors to digitally transmit a full-genome sequence to the Moon, where lab techs would synthesize the DNA (perhaps along with the mitochondrial genome!) and implant it into a “blank” stem cell. From there, an organ could be delivered much more cheaply down to Earth.

Still, that would only mildly alleviate the problem. As mentioned up top, human biology functions under normal gravitational conditions; while working in space can certainly be useful for some people, the more fruitful approach overall is likely learning how to control biology on the ground.