Project printing human tissue in space could enable distant exploration – and treatment of disease on Earth

Humans are not meant to live in space. Beyond the protection of Earth’s atmosphere and magnetic field, astronauts are assaulted by a host of ‘space stresses,’ including radiation, microgravity and isolation.

“That obviously has an effect on their health,” said Dr Marco Domingos, senior lecturer in mechanical and aeronautical engineering at the University of Manchester. “One of the most well-known is the impact of the absence of gravity in bone density, that results in severe fractures – and that is normally a problem, especially if you are thousands of miles away from Earth.”

To start addressing the issue, researchers need to understand the impact of space stresses – but studying it in astronauts is very difficult, and there are ethical issues around using animal models. Bioprinting offers another way. 

A two-year project at Manchester is exploring use of the technique – 3D-printing living cells to create skin, bone, tissue or organs – to address the “critical health challenges” faced by astronauts. 

Currently, bioprinters rely on Earth’s gravity to function effectively. The new research, funded by a £200,000 grant from the UK Space Agency, seeks to understand how to optimise the bioprinting process for microgravity.

The project, supported by the European Space Agency (ESA) and feeding into the organisation’s Terra Novae exploration programme, aims to install a bioprinting station aboard the International Space Station. 

Accelerated development

Working with ESA, Domingos and colleagues at the Henry Royce Institute have informed the development of an extrusion-based bioprinter. The device will print both bone marrow stem cells and embryonic stem cells, attempting to replicate the structure and composition of bone and skin as closely as possible.

European partners will then study those tissues as they undergo the effects of microgravity and radiation in space. Those conditions can accelerate the onset of certain diseases, allowing them to be detected and studied in a much shorter timeframe than usual. This, in turn, could lead to much quicker development of therapies for use on Earth. 

The long-term vision is to provide healthcare for deep-space missions or extra-terrestrial settlements. “We need to have, on-site, the capacity to produce tissue grafts to either replace a damaged bone caused by a fracture, or a wound in the skin, or even entire organs,” said Domingos. The lack of gravity could actually aid the printing of organs, he added.

Growing food and oxygen

Even more ambitious applications are possible in future, according to Domingos, who said he is in regular conversation with the ESA about potential projects. The team hopes to progress beyond the challenge of microgravity to overcome other hurdles including preserving, transporting and processing cells in space, for example.

The next five to 10 years will likely see an explosion of experiments being sent to low Earth orbit, the researcher predicts, as international groups seek to tackle the challenges of space exploration. This will be followed “very, very quickly” by the formation of small settlements on the Moon, he claimed. 

The most immediate application of bioprinting will be for medicine, he said. “But think about, for example, the use of cells and other non-mammalian cells for the production of oxygen, or for the production of food, because most of the things that we’re going to be using on the Moon and other planets, they need to be sourced locally. We need to have that ability, and bioprinting will play a crucial role in that as well.”