Tag Archives: scaffold

World first lab grown organ transplant

A 36-year-old man is recovering after surgeons implanted the world’s first wholly lab-grown organ into his body.

The synthetic trachea, or windpipe, was created by seeding the patient’s own stem cells on to an artificial “scaffold”. British scientists helped design and build the structure, an exact replica of the man’s original windpipe.

Windpipes have been grown from stem cells before, but only using the collagen “skeletons” of donated tracheas. Using an entirely synthetic scaffold means patients do not have to wait for a suitable donor organ.

This is especially important for children, for whom donor tracheas are much more difficult to find.

The patient, an African student living in Iceland, had been suffering from life-threatening tracheal cancer.

The lab-grown windpipe

The lab-grown windpipe

Spanish regenerative medicine pioneer, Professor Paolo Macchiarini, led the operation at Karolinska University Hospital in Sweden. In 2008 he carried out the world’s first tissue-engineered tracheal transplant on a 30-year-old Spanish woman, Claudia Costillo.

Professor Alexander Seifalian, from University College London, worked with Professor Macchiarini to produce the synthetic trachea scaffold. He said: “This is the first time that a wholly tissue-engineered synthetic windpipe has been made and successfully transplanted, making it an important milestone for regenerative medicine.”

The Y-shaped structure was made from a plastic-like “nanocomposite” polymer material consisting of microscopic building blocks. The material had previously been developed and patented by Prof Seifalian.

To guide the process, CT (computerised tomography) scan images were obtained of the patient’s damaged trachea. These were used to produce a glass mould for the nanocomposite structure.


The scaffold was taken to Sweden, where it was “seeded” with stem cells from the patient’s own body. The prepared trachea was then placed in a “bioreactor”, a device providing the right environment for growth.

After just two days the stem cells had grown into tracheal cells ready for transplantation.

Since the organ was built from cells originating from the patient, there was no risk of it being rejected by his immune system.

Prof Seifalian said: “Professor Macchiarini has previously performed successful transplants of tissue engineered tracheas, but on those occasions the tracheas used were taken from organ donors and then reseeded with the patient’s own stem cells.

“What makes this procedure different is it’s the first time that a wholly tissue-engineered synthetic windpipe has been made and successfully transplanted, making it an important milestone for regenerative medicine. We expect there to be many more exciting applications for the novel polymers we have developed.”

The patient is said to be doing well and is due to be discharged from hospital tomorrow.

Tamarind used to treat Parkinson’s disease

A compound from tamarind tree could help spur the growth of damaged brain and spinal cord nerve cells, which characterises diseases such as Parkinson’s.

Doctoral student Andrew Rodda from Monash University’s materials engineering team investigated xyloglucan, a compound from tamarind seeds and how it affects animals with damaged nerves.

The derivative that Rodda developed from xyloglucan can be injected into an injury site as a liquid, before becoming a gel as it reaches body temperature.

Once in place, it acts as a support structure through which healthy cells can migrate and potentially reattach themselves to the nervous system.

Tamarind

Tamarind

Until now, all damage to the nerve cells of the central nervous system – the brain and spinal cord – had been considered irreparable, according to a Monash statement.

Rodda said the lack of repair or regrowth is due mainly to the toxic environment left behind after nerve death. “Nerve cells are sensitive, and will only grow in the most supportive of environments.”


“After injury, new cells cannot normally penetrate into the empty space left after mass cell death. Cells clump at the edges, forming an impenetrable barrier. This leaves the centre of the wound as a lesion, which contains chemicals that kill growing nerves.”

Rodda said the new compound works by providing a temporary scaffold on which new cells can grow and penetrate the lesion.

Significantly, it was the helper cells, known as astrocytes, which were the first to move into the implanted gel. These cells secrete beneficial chemicals, which may have helped create an environment in which the delicate nerve cells can survive.