WASHINGTON — Redwire announced it successfully 3D-printed human tissue in microgravity, a step towards more ambitious biotech applications in space.

The company said Sept. 7 that a human knee meniscus, printed on its 3D BioFabrication Facility (BFF) on the International Space Station, was now in the lab on Earth after returning on the Crew Dragon spacecraft that brought Crew-6 back to Earth Sept. 4. The meniscus was printed on the station in July.

The experiment was performed with the Uniformed Services University, which is looking for improved treatments for injuries like meniscus tears that are common among service members. For Redwire, the experiment was a way to demonstrate the ability of the BFF to print tissues for broader applications.

“For us, it’s a great target tissue to go after,” said Ken Savin, chief scientist at Redwire, in an interview. “It allows us to test out our ability to put cells into this type of system, to look at their viability and it’s, in a way, a jumping off point to other tissues that we’re going to we also investigate.”

One particular area of interest is being able to produce human tissues for pharmaceutical applications, like model development. “Being able to develop any type of tissue that you want in space in the future has distinct advantages,” he said. “It will lead us down the path towards model development, tissue replacement therapy and, ultimately, organ replacement therapy as well.”

That bioprinting can’t be done easily on Earth because of gravity. “Generally you have to add chemicals or some kind of structure or framework that allows you to print in that third dimension. Otherwise, it all settles into a puddle,” he explained. “By printing in space, things that are only slightly more viscous than water can be printed into three dimensions.”

Redwire is planning another experiment for the BFF set to launch in November on a cargo Dragon mission that will involve printing cardiac tissue. That will test how it can print more sophisticated tissues, he said, including the ability of the cells to operate in rhythm.

“It also leads to something that we do believe ultimately is of real significance,” he added. “I think heart tissue therapy is a big deal and one that we see value in delivering.”

Savin said Redwire is seeing growing interest in doing experiments using the BFF or other facilities on the space station from the pharmaceutical community. “What I’m starting to see is that normal everyday scientists in America are submitting experiments to be done in space,” he said, including scientists that have not traditionally done microgravity research. “We can talk about those opportunities and try to make an experiment that will test out their hypothesis in space. It’s doable and it happens.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...