July 31, 2013
Scientists Grow Human Ear In Lab From Animal Tissue
Lee Rannals for redOrbit.com - Your Universe Online
Scientists from Massachusetts General Hospital in Boston say they have grown a human-like ear from animal tissue in a lab.
The new ear, reported in the Journal of the Royal Society Interface, moves scientists one step closer to growing a complete human ear from a patient's cells. The researchers say their ear has the flexibility of a real ear, and the technique may one day be used to help people with missing or deformed ears.
The scientists took living tissues from cows and sheep and grew them on a flexible wire frame that has the 3D shape of a real human ear. They then implanted the ear onto a rat whose immune system had been suppressed to enable the ear to grow.
"We've demonstrated the first full-sized adult human ear on the rat model," Dr Thomas Cervantes, who led the study, told BBC News. "One - we were able to keep the shape of the ear, after 12 weeks of growth in the rat. And then secondly we were also able to keep the natural flexibility of the cartilage."
Researchers grew the cells on a titanium wire scaffold that is modeled on the dimensions of a real human ear. The work shows that it is possible to grow enough cells to make a full-size human ear.
"In a clinical model, what we would do is harvest a small sample of cartilage, that the patient has, and then expand that so we could go ahead and do the same process," Dr Cervantes told BBC. "This research is a significant step forward in preparing the tissue-engineered ear for human clinical trials."
The researcher said he hopes the process could move into human clinical trial in about five years.
Last year doctors at John Hopkins Hospital were able to grow a replacement ear for a cancer patient on her own arm. The patient, Sherrie Walters, became the first person to receive a replacement ear developed from her own rib cartilage.
Walters developed basal cell carcinoma cancer, which led to the amputation of a portion of her left ear, skull and ear canal. The original procedure left her left side disfigured and deaf in her left ear. The doctors used cartilage from the rib cage to create a new ear that matched her right one. The ear was then implanted under the skin of her left forearm in November, where it grew for four months before being transplanted onto her head.