Custom-made, living body parts have been 3D-printed in a significant advance for regenerative medicine, say scientists. The sections of bone, muscle and cartilage all functioned normally when implanted into animals.
The breakthrough, published in Nature Biotechnology, raises the hope of using living tissues to repair the body. Experts described the technology, developed in the US, as a « goose that really does lay golden eggs ».
The idea of placing individual human cells in a precise pattern to replace a damaged jaw, missing ear or scarred heart muscle holds much promise. But the field has been limited by the huge challenge of keeping the cells alive – they become starved of oxygen and nutrients in tissues thicker than 0.2 millimetres.
The team at Wake Forest Baptist Medical Centre developed a new technique that 3D-prints a tissue riddled with micro-channels, rather like a sponge, to allow nutrients to penetrate the tissue.
The Integrated Tissue and Organ Printing System – or Itop – combines a bio-degradeable plastic which gives the structure and a water-based gel which contains the cells and encourages them to grow. When the structures were implanted into animals, the plastic broke down as it was replaced by a natural, structural « matrix » of proteins produced by the cells. Meanwhile, blood vessels and nerves grew into the implants. Prof Anthony Atala, the lead researcher, said tissues could now be printed on a human scale. While the implants have the same strength as human tissues, the researchers are now waiting to see how durable they are. But Prof Atala said 3D printing was opening new doors for medicine.
SOURCE: BBC News