Surgeons have successfully transplanted a 3-D-printed ear made from living tissue onto a 20-year-old woman in a groundbreaking procedure. The implant, called AuriNovo, was constructed from the woman's own cells, reports Roni Caryn Rabin for the New York Times.
The 20-year-old patient was born with the congenital disorder microtia, which caused a misshapen right ear. In March, the woman received a 3-D-printed, lab-grown implant of a right ear created from cells from her left ear, in a shape that gave her two matching ears. The lab-grown ear was created by the regenerative medicine company, 3DBio Therapeutics. The ear will continue to grow and generate cartilage tissue now that it’s been implanted, giving it a natural look and feel. 3DBio Therapeutics announced the results of the reconstructive surgery in a release published this month. The company’s has also started a clinical trial, expected to finish in 2028, with 11 microtia patients [SJ1] who will receive 3-D printed implants. The clinical trial will track the compatibility of the ear and its function over the long term.
The possibility exists that the transplanted ear could be rejected by the body’s immune system as a foreign object and bring on health complications. 3DBio Therapeutics officials hope that rejection won’t happen since the implants are made from the patients' cells, per the New York Times. In the past, other companies have used 3-D printing technology to produce custom prosthetic limbs from lightweight plastics and materials. Still, the ear is the first known example of a 3-D implant made from living tissue.
AuriNovo, the 3-D-printed ear, is patient-specific and is intended to be used for surgical reconstruction in humans born with microtia, per a statement. An estimated 1,500 babies born in the United States annually have microtia. The condition causes one or both ears to be underdeveloped or missing entirely. Microtia patients can have new ears made from silicone or even rib grafts, where surgeons must scrape cartilage from a patient's rib cage and then carve it into the approximate shape of an ear. 3DBio Therapeutics instead uses an experimental process where a biopsy is taken from the patient's existing ear, and cartilage cells are harvested, reports Nicole Wetsman for the Verge. The cells are then grown in a lab until enough cells have accumulated to be used as the physical printing material, like ink on a page, for a patient’s unique ear shape. The exact technical details of the printing process have not yet been released by 3DBio, citing proprietary concerns.
Researchers at 3DBio first built a 3-D computer model based on a scan of the woman's left ear. Then, they cultured cells from the left ear and put them into "bioink,” a somewhat gelatinous material made from collagen that mimics that 3-D architecture of the space between cells. The printer then deposited the collagen ink layer by layer into the shape of the patient's right ear[SJ2] , an exact copy of the left ear flipped around. Once the ear was printed, a biodegradable shell was placed over the ear and shipped in cold storage reports to a doctor, according to the Times. The doctor then implanted the ear under the patient’s skin.
Adetola Adesida, a professor of surgery and biomedical engineering at the University of Alberta, who was not involved with the research, told NBC News that the 3-D printing method avoids infection and surgical risks because doctors won't have to go into the rib cage and expose the lungs. With more research, 3DBio Therapeutics says their technology could be used to 3-D print other body parts like spinal discs, noses, rotator cuffs, knee menisci and other tissues, the New York Times reports.