An astronaut looks down at Earth through the window of the International Space Station, while a floating ball of heart cells rolls out of a 3D printer. It sounds like a distant vision, but as far as Lorenzo Moroni, professor of biofabrication for regenerative medicine is concerned, this will be a reality in twenty years’ time. For this reason, the MERLN Institute for Technology-Inspired Regenerative Medicine in Maastricht will collaborate with space agencies ESA and NASA from April to print human tissue in space.
Upon entering, Moroni mainly talks about the layout of the office: “Everyone is mixed up here, from master’s students to senior researchers. This is how the best ideas are born.” Moroni has been researching regenerative medicine for twenty years, treatments that aim to repair cells, organ functions and tissues in the human body.
With regenerative processes you can think of the tail of a salamander that grows back. Or the antlers of a deer that return again and again. Regeneration also occurs in the human body. Cells in tissues die but are also replenished by new ones. In this way, our body is completely renewed every seven years and all cells are replaced by new cells.
“Here in Maastricht we look at how new technologies can be used to quickly repair organs, bones or muscles in the human body when there is damage,” explains Moroni. “Think of repairing deep wounds, or strengthening the heart muscle with new tissue.” That is why printing biological material, bio printing, one of the most important techniques. And according to Moroni, the best way to develop this technology is 400 kilometers above our heads: in the ISS.
How do you print biological material?
“We do not print with ink, but with a gel full of stem cells that comes out of a kind of glue gun. These cells adapt to the type of tissue you want to repair. If blood vessels are damaged in a deep cut, we print endothelial cells that promote repair of such a wound. For damaged heart muscle, you print stem cells that develop into so-called cardiomyocytes. These cells can die due to lack of oxygen. The resulting scar tissue often causes cardiac arrhythmias that provoke another heart attack. If you print cells and repair the tissue, you can reduce the chance of a recurrence.”
The next step is that we will test this for minor damage to humans, such as a deep cut
What does printed fabric look like?
“It can be a flaky piece of tissue, but we can also integrate the cells into, for example, plasters that you stick on a wound and then help the wound to heal.”
But do those cells attach directly to the damaged tissue?
“Not always, you need so-called carrier material for that. In our body, tissue in addition to cells is made up of a protein structure, in which the cells nestle. For new cells, we mimic that protein structure with a biodegradable gel. This gel initially acts as a carrier material for the cells we insert. When the cells start to divide, they gradually build their own protein structure and our gel decays. In this way, a tissue can grow into a bed of proteins that grows with it.”
Are these printed fabrics already being used for humans?
“No, we can now grow tissue in a controlled manner in the lab. The next step is that we will test this for minor damage in humans, for example for a deep cut that does not heal on its own.
“What is possible: using printed tissues to test new medicines. That works much better than animal testing, because then you test with real human tissue. That saves another step in the entire testing process.”
Aging in the body goes faster in space due to cosmic rays
Why do you want to print in space?
“There is gravity on Earth. When we print tissue here, we do it on a flat surface, because the gel full of cells simply falls down. This creates layers in how cells are arranged, comparable to the layers in a spekkoek. When they grow out, they do so in layers. That’s not how it happens in our body. There is no gravity in space, so you can print three-dimensionally. This allows us to imitate tissue structures much better. Round, angular, which cells should be placed where in the protein structure, in space we have control over many more factors than on Earth.”
What does that space fabric look like?
“Perhaps you know the floating droplets of videos from the ISS. We can arrange our cell droplets by means of sound waves and magnetic forces, exactly as they are structured in the body. That is really only possible in the absence of gravity.”
So you make tissues in space and then bring them back to Earth?
“No, we will also conduct experiments there. Aging in the body goes faster in space because cells are more damaged by cosmic rays. If we simulate tissues in space, we can detect that damage much more quickly, while we have to wait years for this on Earth. As a result, we learn more precisely how tissues grow and age. Take the growth of cardiomyocytes in the heart. These cells grow and divide until we reach adulthood, but then that whole process stops. Why is it like that? Our rapidly aging tissues can provide insight into this.”
One in five people dies of cardiovascular disease, I want to do something about that
You are only going to look at the heart in this space exploration, why?
“Well, it is a bit like the engine of our body, but we hardly know how it repairs itself after a heart attack, for example. One in five people dies of cardiovascular disease, I want to do something about that. My uncle was a heart surgeon in Italy and saved so many lives that way. I want that too, but then with printed tissues in which we expose processes that were unknown until now.”
Why are space agencies NASA and ESA actually involved in this project?
“NASA and ESA plan to take humans to the moon and Mars for an extended period of time within ten years. If people get injured there or suffer from other damage in the body, there is no medical help. Printing cells could help them do that. In addition, the experiments we want to do must be carried out by trained astronauts, so we really need them to make this project a success.”
You have not planned a space trip yourself?
“No, not yet. But if I can, I will definitely go.”