Microtia and Aural Atresia Center Research
The Microtia and Aural Atresia Center at Mass. Eye and Ear has been working with Dr. Joseph Vacanti, Director of the Tissue Engineering and Organ Fabrication Laboratory at Massachusetts General Hospital, and Catherine Sundback, who have spent years developing a technique of growing cartilage over biodegradable molds to custom shape cartilaginous body parts, such as ears. In a famous experiment, the team used cartilage from a cow’s knee, placed it in a biodegradable mold shaped like a three-year-old’s ear and implanted it under the skin of a special “nude” mouse (“nude” mice have very weak immune systems and won’t reject foreign tissue). Over time, the mouse grew extra blood vessels that supplied nourishment to the “ear.” The “ear” was never transplanted onto a human because the cow cells would have been rejected by a child’s immune system.
Even though tissue engineering frameworks such as the “mouse ear” are not yet a practical option in reconstructive ear surgery, the technology and concept are very promising and being studied rigorously.
Tissue engineering combines living cells, engineering and materials techniques, biochemical and physiochemical factors to improve or replace tissue. Serious attempts at tissue engineering began in the early 1980s. Cartilage, being avascular (not supplied by blood vessels), was an ideal medium to begin with, which quickly led to trials in microtia repair.