Half a millennium after Johannes Gutenberg printed the bible, researchers printed a 3D splint that saved the life of an infant born with severe tracheobronchomalacia, a birth defect that causes the airway to collapse.
While similar surgeries have been preformed using tissue donations and windpipes created from stem cells, this is the first time 3D printing has been used to treat tracheobronchomalacia — at least in a human.
Matthew Wheeler, a University of Illinois Professor of Animal Sciences and member of the Regenerative Biology and Tissue Engineering research theme at the Institute for Genomic Biology (IGB), worked with a team of five researchers to test 3D-printed, bioresorbable airway splints in porcine, or pig, animal models with severe, life-threatening tracheobronchomalacia.
“If the promise of tissue engineering is going to be realized, our translational research must be ‘translated’ from our laboratory and experimental surgery suite to the hospital and clinic,” Wheeler said. “The large-animal model is the roadway to take this device from the bench top to the bedside.”
For more than 40 years, pigs have served as medical research models because their physiology is very similar to humans. In addition to tracheobronchomalacia, pigs have been biomedical models for muscular dystrophy, diabetes, and other diseases. The team chose to use two-month-old pigs for this study because their tracheas have similar biomechanical and anatomical properties to a growing human trachea.
“Essentially, all our breakthroughs in human clinical medicine have been initially tested or perfected in animal models,” Wheeler said. “Through the use of animal models, scientists and doctors are able to perfect techniques, drugs, and materials without risking human lives.”
First, Wheeler sent a CT scan of a pig’s trachea to Scott Hollister, a professor of biomedical engineering at the University of Michigan. Hollister used the CT scan and a 3D CAD program to design and print the splints. These devices were made from an FDA-approved material called polycaprolactone or PCL, which Wheeler has used in more than 100 large-animal procedures.