Stem cells used to grow human ear on rat

27/01/2016

For the first time, stem cells have been used to grow an adult-sized human ear on a rat.

The University of Tokyo and Kyoto University scientists behind this feat said that such ears could be grown to help patients with disfigured by conflict or accidents, and those born without ears or with ear deformities.

In the US alone, between one and five out of every 10,000 children born have a missing ear or some form of ear deformity.

To grow the ear, the scientists triggered pluripotent stem cells – which have the potential to transform into almost any cell in the body – to grow into ear cartilage. The cells were then placed into biological tubing shaped like an ear, which was then implanted under the skin of a live rat. After approximately two months, the tubes dissolved and left behind the ear.

Stem cells taken from a patient’s body are the only way to ensure a perfect match for stem cell transplants and avoiding the risk of the body rejecting them, forcing the patient to take anti-rejection drugs for the rest of their life.

As such it makes sense to harvest and store stem cells, and the least painful and invasive method of doing so is to harvest them from naturally shed teeth. The best quality stem cells are those taken from baby teeth as they have not yet begun to deteriorate due to age or pollutants.

In 2013, a Massachusetts General Hospital team grew an ear on a titanium wire frame shaped like an ear using collagen from cows and cells from sheep. Tissue engineering such as this is also being used to grow other kinds of body parts such as noses and windpipes.

The scientists said that, because the ear they grew is a living part it would grow naturally with any child it was transplanted to.

They hope to be able to begin clinical trials within the next five years.