3D bioprinted human cartilage grown in mice for ‘first time’

Researchers have successfully grown human cartilage cells in animals for the first time using 3D bioprinting.

While 3D printing is commonly used in a wide range of engineering sectors and the medical sector, using the technology to print human tissue is still new. Referred to as bioprinting, the approach uses a computer-controlled 3D printing device to precisely place cells and biomaterials. It has been used to print simple fake organs like an child’s ear, as well as layers of skin and cartilage.

However, Swedish researchers at Chalmers University are claiming that they have become the first to grow bioprinted cartilage in live animals. It could one day lead to replace injured or diseased cartilage and bone in human patients.

The team led by Professor Gatenholm, who specialises in tissue engineering, printed a water-based gel of nanocellulose (natural fibers – typically made from wood pulp) mixed with human cartilage cells  to make a so called ‘construct’.

They used a 3D bioprinter manufactured by Cellink, a Gothenburg-based startup firm whose bio-ink is a result of research by Gatenholm. Immediately after printing, the construct was implanted in mice.

The researchers grew the human cartilage tissue in the mice, saw blood vessels grow between the materials, and the creation of new cartilage made by human stem cells.

“What we see after 60 days is something that begins to resemble cartilage. It is white and the human cartilage cells are alive and producing what they are supposed to,” said Lars Kölby, plastic surgery consultant who worked on the project.

Gatenholm is careful to point out that the results he and Kölby’s team have found are not a “short cut to bioprinted organs”.

He hopes that the research will be a step towards someday being able to bioprint cells that “become body parts for patients”.

“This is how you have to work when it comes to this kind of pioneering activity: one small step at a time. Our results are not a revolution – but they are a gratifying part of an evolution," said Gatenholm.

Gatenholm has also been involved in research at Wake Forest Institute for Regenerative Medicine, North Carolina. In 2016, the US researchers used a 3D printer to build complex chunks of muscle, cartilage, and even bone.

There are a range bioprinters from companies such as EnvisionTec and Organovo available to buy, including cellular inkjet printers, laser-assisted bioprinters, stereolithography and extrusion-based printers. These can range in price between £8,000 and £160,000.