Stem cells could be used to repair brain damage

It may soon be possible to repair damage to the human brain by reactivating stem cells within the body that can grow on specially constructed "biological scaffolding" inserted into the brain, scientists say.

The hope is that the brain could be regenerated in the same way that tissue can regrow in animals such as salamanders and fish where nerves are capable of repairing themselves in the same way the human body can repair skin or bone. Mike Modo, of the Institute of Psychiatry, in London said that medical scaffolds made of synthetically made biological materials inserted into the brain could provide the structural framework for naturally existing stem cells to repair damaged regions caused by strokes or trauma.

"If we have damage to the brain, we are trying to put biomaterials in there to provide a structure for these cells to attach and to start forming connections between each other and eventually, hopefully, to regenerate the tissue that has been lost," Dr Modo said.

"Theoretically the hope is that these biomaterials can be guided to support these cells and that they can be engineered to secrete particular [growth] factors," he said.

More than 180,000 people each year in Britain suffer from brain damage caused by strokes. Brain damage is often permanent because at present there is no way of regenerating nervous tissue to repair the cells that have been killed.

Professor Andrea Brand of the Gurdon Institute at Cambridge University said that the human brain was known to contain inactive stem cells and one possibility was to reactivate them so that they could begin to replace lost cells, which was what probably happens in the brains of salamanders and fish.

"We know there are stem cells in the human brain. If we can reactivate stem cells that are in the right place at the right time, that would be ideal," said Professor Brand, who is speaking today at the British Neuroscience Association meeting in London.

"We know that stem cells will sometimes go to sleep and we're studying ways of reactivating them. This is really key because what we'd like to do eventually in terms of repairing the brain is to reactivate someone's own stem cells in situ to give rise, hopefully, to the neurons that will replace those that have been damaged," Professor Brand said.

"In particular, we are interested in how these stem cells can generate all the different types of nerve cells that you find in the human brain," she said.

The human brain contains about 100 billion neurons, or nerve cells, and scientists are studying the simpler nervous systems of laboratory animals, such as fruit flies, to find the genes that are involved in turning stem cells off and on.