Bio bandages from a 3D printer: BIH and Cellbricks test printing in zero gravity

Researchers from the Berlin Institute of Health at Charité – Universitätsmedizin Berlin have jointly developed a 3D bioprinter together with the Berlin-based company Cellbricks that can produce individually customized wound dressings from living skin cells. The system is aimed at treating large-area burn and abrasion wounds and has now been tested for the first time under conditions of changing gravity. The results were published in the scientific journal Advanced Science.

Despite modern medicine, extensive burn injuries are still considered problematic. They are usually treated with autologous skin grafts, in which healthy skin is removed and transplanted onto the wound.

Professor Georg Duda, Director of the Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration at BIH, said: “Unfortunately, scarring often occurs, which is neither medically nor cosmetically satisfactory for doctors or patients.”

The bioprinter that was developed uses a so-called bio-ink made of living skin cells and a modified gelatin. This material hardens using digital light processing under UV light.

“The printer ink is based on a mixture of living skin cells and a modified gelatin that hardens when exposed to UV light,” explains Bianca Lemke, first author of the study and doctoral candidate of Professor Duda. In what is known as digital light processing (DLP), the bio-ink solidifies layer by layer into the shape specified by the UV light. The shape and size of the required wound closure can be individually adjusted. “The consistency of the print resembles a gummy bear. The technology also makes it possible to print small channels, allowing the integration of blood vessels.”

“Such an individualized solution for burn wounds would also be practical for astronauts on the ISS or on the way to Mars,” says Georg Duda. “And that’s how, at a symposium of the German Aerospace Center (DLR), the question arose as to whether 3D bioprinting could also be used for space travel.”

Particular focus was placed on usability in space. Against the backdrop of planned long-term missions by space agencies as well as private actors such as SpaceX and Blue Origin, the team investigated whether bioprinting also works without Earth’s gravity. During parabolic flights, organized with the support of the German Aerospace Center, the system demonstrated stable printing results despite rapid changes between weightlessness and hypergravity. Cell viability and dimensional accuracy were maintained, even though cell distribution changed under high stress.

“Weightlessness would in itself provide perfect conditions, because no forces act on the print,” Bianca Lemke estimates. “During a parabolic flight, however, this only lasts for 21 seconds per parabola, and therefore we investigated how robust printing is under the very strongly fluctuating gravitational conditions of a parabolic flight.”

“With these printing results, we could actually one day offer astronauts personalized wound care and also significantly improve burn treatment for patients on Earth,” says Georg Duda. “Even if there is still a long way to go.”

In the long term, those involved see opportunities for personalized wound care on the International Space Station and during future missions. At the same time, the findings could further advance the treatment of severe skin injuries on Earth, although extensive testing will still be required before clinical application.