NZ brain disease breakthrough

Motor neurone disease sufferer Willy Terpstra had to travel to China last year for stem cell therapy because it wasn't available in New Zealand. Picture / Alan Gibson

Scientists in Auckland have made a breakthrough in adult stem cell transplants that could mean a brighter future for people with Huntington's disease and other neurological conditions.

Neuroscientists at Auckland University, working on rats, have for the first time successfully transplanted a viable number of adult stem cells, enabling brain cells destroyed by Huntington's to be replaced.

The discovery also has important implications for treating spinal cord injuries and diseases where specific cell types are lost, such as Parkinson's and motor neurone disease - conditions where cell transplants are a potential remedy.

The study, funded by the Neurological Foundation, is due to appear in the science journal Experimental Neurology.

"Although stem cell therapy treatment for humans is still a number of years away, the results clearly demonstrated what adult stem cells are capable of doing," said Dr Bronwen Connor, leader of the study and head of the Auckland School of Medicine's Neural Repair and Neurogenesis Lab.

Stem cells are cells that divide and differentiate into other cell types, acting as a repair system by replenishing destroyed or damaged cells in the body.

Stem cells are now harvested from human fetal tissue, a controversial source loaded with ethical and moral dilemmas.

As the process is banned in New Zealand and most other countries, motor neurone sufferer Willy Terpstra was forced to travel to China last year for stem cell therapy which involved around two million cells from an aborted fetus being transplanted into her brain.

The latest study saw Auckland researchers use adult stem cells obtained from the brains of healthy rats which were then transplanted into rats with Huntington's disease.

Two months after transplant, a significant number of adult stem cells had survived and formed the type of brain cells needed to replace the cells lost in Huntington's. Most importantly, the rats also showed a marked improvement in control over muscles and movement.

Dr Connor said the treatment appeared to work well because the transplanted cells tended to naturally default to the particular cell-type affected in Huntington's.

In the study, about 12 per cent of adult stem cells survived the transplant, of which only a small proportion turned into the needed replacement cells.

"But the amount was enough to have an improvement in motor function, which was exciting for us," said Dr Connor.

Its potential would also enable doctors to use a patient's own cells, which would bypass many transplant problems, she said.

"A lot of our work is looking at using the resident stem cells that are present in the brain and trying to actually get those cells to repair brain disease and brain injury.

"And we have several studies showing that this does occur and that this is possible, and we've got a couple of papers that will be coming out soon showing that we have actually augmented that whole process."

Dr Connor's team will next look at improving the stem cell survival rate following transplant.

Professor Richard Faull, a world expert on the human brain and a colleague of Dr Connor, said the discovery was an important step in demonstrating the potential of stem cells, which are found throughout the adult brain.

"This is an important milestone on the pathway of giving patients a better future. But it's not going to result in a therapy tomorrow, or next year, or the next three years.

"There is still a long way to go."


Treatment targets

Huntington's: Hereditary disease affecting about 15,000 New Zealanders. Every child of a Huntington's sufferer has a 50 per cent chance of inheriting it. The disease destroys cells in the part of the brain that controls movement. Symptoms include involuntary jerking, slurred speech and gradual loss of mental ability.

Parkinson's: Progressive neurological condition that affects about 8000 New Zealanders. Three main symptoms are tremors, stiffness and slowness of movement.

Motor neurone: Name for a group of conditions where the cells governing movement become weak and eventually waste away. Symptoms include twitching, muscle cramp, general fatigue. Speech, swallowing and breathing are affected. Between 200 and 250 New Zealanders have the condition.