Aboard the ISS, a bioprinter builds cartilage tissue in microgravity

On October 9, 2026, NASA astronaut Jessica Watkins stood inside the Life Science Glovebox of the Kibo laboratory module, aboard the International Space Station. She mixed living cell samples with a bioink, the gel that carries cells, then filled a special cartridge with the mixture. A bioprinter uses that cartridge to build tissue layer by layer, the way a desktop printer lays down ink.

The experiment is called InSPA-Auxilium Bioprinter-Cell Printing. It studies 3D bioprinting of cartilage in microgravity, the tough, flexible tissue that cushions joints. The need is large: NASASpaceFlight reports that over 900,000 knee cartilage injuries occur each year in the United States alone, and up to 200,000 of them require surgery.

On Earth, the cells tend to settle while the ink sits in the printer. In orbit, that settling disappears. NASASpaceFlight says this allows printing of more uniform, higher quality tissue than on Earth, and NASA describes the goal in the same terms: cartilage of higher quality than the Earth-made version. These are expectations, not yet measured results for patients.

Auxilium Biotechnologies reports further results from its AMP-1 orbital bioprinter. The company says the printer made kidney, liver and cartilage tissues in orbit, and produced 28 nerve-repair implants, which it presents as a first for kidney and liver tissue in space. These are the company's own figures, and they have not yet been reproduced by an independent team in the material available here.

Who gains, and when? Patients with cartilage damage would be the first beneficiaries if the method reaches clinical use, and crews on long missions could one day print tissue on board. Neither NASA nor Auxilium gives a date for that. For now, the work is research: cells printed in orbit, tested and analysed, with no tissue yet in a patient.