Technology could be used to replace ears, bone and muscle
Living tissue structures can be printed to replace injured or diseased tissue in humans, research by the Wake Forest Baptist Medical Centre has found.
Using a custom-designed 3D printer, the scientists produced ear, bone and muscle structures. When implanted in animals, the structures grew into functional tissue and developed a system of blood vessels.
The study, published in Nature Biotechnology, suggests that the structures have the right size, strength and function for use in humans.
“This novel tissue and organ printer is an important advance in our quest to make replacement tissue for patients,” said Anthony Atala, M.D., director of the Wake Forest Institute for Regenerative Medicine (WFIRM) and senior author on the study.
“It can fabricate stable, human-scale tissue of any shape. With further development, this technology could potentially be used to print living tissue and organ structures for surgical implantation.”
The team developed the Integrated Tissue and Organ Printing System (ITOP) over 10 years. It deposits both bio-degradable, plastic-like materials to form the tissue “shape” and water-based gels that contain the cells. A strong, temporary outer structure is then formed on the outside.
To keep the cells alive, the scientists optimised the water-based “ink” that holds the cells so that it promoted cell health and growth. They also printed a lattice of micro-channels throughout the structures. These allow nutrients and oxygen from the body to diffuse into the structures and keep them live while they develop a system of blood vessels.
The scientists say that the ITOP system can also use data from CT and MRI scans to “tailor-make” tissue for patients. For a patient missing an ear, for example, the system could print a matching structure.
The team are now conducting further studies to measure longer-term outcomes.
Image (C) Wake Forest Institute for Regenerative Medicine
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