Human health remains one of the greatest challenges in space exploration. When astronauts spend long periods in space, their bodies weaken dramatically—especially their muscles and bones. Now, scientists at ETH Zurich have taken a major step toward solving this problem by successfully 3D-printing human muscle tissue in zero gravity for the first time.
Their groundbreaking work, published in *Advanced Science*, could pave the way for new methods to study diseases and test medicines in space. To simulate the microgravity environment of space, the research team led by Parth Chansoria conducted their experiments during parabolic flights—special aircraft flights that follow an up-and-down trajectory, creating brief periods of weightlessness.
During these fleeting moments of zero gravity, the researchers were able to print tiny, realistic pieces of muscle tissue without the interference of Earth’s gravity.
Printing delicate biological structures such as muscle tissue is a challenging process on Earth. Scientists use a special material known as bio-ink—a gel-like substance that contains living cells. However, when gravity is present, this mixture can sink or deform before it hardens. This often causes 3D-printed structures to collapse or lose their shape, resulting in uneven and less lifelike models of human tissue.
In contrast, microgravity eliminates these issues. The bio-ink and cells remain perfectly suspended, enabling scientists to build muscle fibers that are precisely aligned—just like in the human body. This alignment is critical for creating realistic tissue models needed to accurately study disease progression and drug effects.
To achieve this breakthrough, the ETH Zurich team designed an innovative 3D bioprinting system called G-FLight (short for Gravity-independent Filamented Light). This high-speed printer can produce detailed muscle tissue models within seconds.
During their parabolic flight experiments, the researchers completed 30 cycles of weightless printing using a specially developed bio-resin that keeps the cells alive and stable. The results were impressive: muscle tissue printed in zero gravity exhibited the same cell health and structural integrity as tissue printed on Earth.
Even more promising is that the cell-laden bio-resins can be stored for long periods. This means they could one day be transported to space for experiments aboard the International Space Station (ISS) or future space laboratories.
This achievement marks a crucial step toward tissue engineering in space. By producing realistic human tissues in orbit, scientists can explore medical questions impossible to study on Earth. For example, these tissue models could help uncover the causes of muscle atrophy—the muscle loss astronauts experience in space—or enable the testing of new therapies for muscular diseases such as dystrophy.
According to the ETH Zurich team, their success brings us closer to a future where scientists can grow complex human tissues—and perhaps even miniature organs—beyond Earth’s gravity. In the long run, this technology has the potential to transform both space medicine and human health research here on Earth.
https://knowridge.com/2025/11/scientists-3d-print-muscle-tissue-in-zero-gravity/
