Researchers see promise in transplanted fetal stem cells for Parkinson's

June 5, 2014, McLean Hospital

Researchers at Harvard-affiliated McLean Hospital have found that fetal dopamine cells transplanted into the brains of patients with Parkinson's disease were able to remain healthy and functional for up to 14 years, a finding that could lead to new and better therapies for the illness.

The discovery, reported in the June 5, 2014 issue of the journal Cell Reports, could pave the way for researchers to begin transplanting neurons taken from grown in laboratories, a way to get treatments to many more in an easier fashion.

"We have shown in this paper that the transplanted cells connect and live well and do all the required functions of nerve cells for a very long time," said Ole Isacson, MD (DR MED SCI), director of the Neuroregeneration Research Institute at McLean and a professor of neurology and neuroscience at Harvard Medical School.

The researchers looked at the brains of five patients who got fetal over a period of 14 years and found that their dopamine transporters (DAT), proteins that pump the neurotransmitter dopamine, and mitochondria, the power plants of cells, were still healthy at the time the patients died, in each case of causes other than Parkinson's.

The fact that these cells had remained healthy indicated that the transplants had been successful and that the transplanted cells had not been corrupted as some researchers had suggested they likely had been in other studies, said Dr. Isacson, lead author of the paper.

"These findings are critically important for the rational development of stem cell-based dopamine neuronal replacement therapies for Parkinson's," the paper concluded.

So far, about 25 patients worldwide have been treated with this particular method of transplanting fetal dopamine cells over a period of two decades and most saw their symptoms improve markedly, he said.

Fetal cell transplants can reduce both Parkinson's symptoms for many years and can reduce the need for dopamine replacement drugs, even though they can take months or years to start working, the paper said.

However, Dr. Isacson said proof had been lacking that the transplanted cells were able to remain healthy—until this study. This is important for research in the transplant field to move ahead, he said.

All of the patients were in the late stages of Parkinson's disease at the time of their transplants. Parkinson's is a disease characterized by tremors, rigidity, slowness of movement and poor balance. It is a chronic, progressive disease that results when dopamine-producing nerve cells in a part of the brain die or are impaired.

Dr. Isacson said there was a need to understand how transplanted neurons could survive despite ongoing disease process in the patients' brains. He said there has been controversy among scientists, some of whom believe that the transplanted cells could be corrupted by toxic proteins associated with the disease process, even at the same time patients seemed to be doing better.

"Everything we saw looked very healthy," he said, referring to the dopamine transporters and mitochondria cells.

He said the method used to transplant the cells into these patients' brains was different than another method used on about 60 other patients worldwide. In some of those other trials, scientists said the cells might have been damaged as a result of the disease process.

It may have been that the method used on the patients in this study, which injected tiny bits of liquefied dopamine nerve cells into the brain via a thin needle, was superior to the method used in other studies, which transplanted larger chunks of nerve cells using a larger needle, he said. The transplants on the patients in this study were done in Canada.

In this study, the researchers led by Dr. Isacson compared the patients' own dopamine producing cells with the transplanted ones. "We found very different patterns," he said.

The difference was seen in the DAT and mitochondria, which were unhealthy around the patients' own and healthy around the transplanted ones. "The transplanted cells don't have the disease," he said.

"This is very important in the quest for new therapies," he added.

It is very difficult to obtain dopamine from fetal tissue, he said. It would be far easier to grow the cells in a laboratory from stem , he noted. There have been no stem cell transplants as of yet for Parkinson's patients.

Explore further: Dopamine-producing neurons derived from bone marrow stem cells yield improvements in monkeys with Parkinson's disease

More information: Cell Reports, Hallett et al.: "Long-term dopamine transporter expression and normal cellular distribution of mitochondria in dopaminergic neuron transplants in Parkinson's disease patients.", www.cell.com/cell-reports/abst … 2211-1247(14)00419-7

Related Stories

Dopamine-producing neurons derived from bone marrow stem cells yield improvements in monkeys with Parkinson's disease

April 22, 2013
Parkinson's disease is a neurodegenerative disorder characterized by the death of dopamine-producing neurons in the midbrain, resulting in motor symptoms such as tremors and stiffness. The cause of cell death remains unknown ...

Stimulating brain cells with light

October 26, 2012
For the time being, this is basic research but the long term objective is to find new ways of treating Parkinson's disease. This increasingly common disease is caused by degeneration of the brain cells producing signal substance ...

Grant for research that could lead to new therapies for Parkinson's Disease

April 22, 2014
A team of scientists led by researchers at Plymouth University Peninsula Schools of Medicine and Dentistry, has received a grant from the Medical Research Council (MRC) for work which could lead to new and effective therapies ...

New treatment targeting versatile protein may protect brain cells in Parkinson's disease

May 16, 2014
In Parkinson's disease (PD), dopamine-producing nerve cells that control our movements waste away. Current treatments for PD therefore aim at restoring dopamine contents in the brain. In a new study from Lund University, ...

Recommended for you

Half of those on Parkinson's drugs may develop impulse control problems

June 20, 2018
Over time, half of the people taking certain drugs for Parkinson's disease may develop impulse control disorders such as compulsive gambling, shopping or eating, according to a study published in the June 20, 2018, online ...

New evidence sheds light on how Parkinson's disease may happen

June 14, 2018
Researchers at Baylor College of Medicine and Texas Children's Hospital have identified unexpected new key players in the development of an early onset form of Parkinson's disease called Parkinsonism. These key players are ...

Scientists unravel molecular mechanisms of Parkinson's disease

June 12, 2018
Detailed brain cell analysis has helped researchers uncover new mechanisms thought to underlie Parkinson's disease.

First photoactive drug to fight Parkinson's disease

June 8, 2018
An international team has designed the first potentially therapeutic photoactive drug, MRS7145, to fight Parkinson's disease, according to the new article in Journal of Controlled Release.

Researchers address sleep problems in Parkinson's disease

June 7, 2018
A team of researchers at VIB and KU Leuven has uncovered why people with a hereditary form of Parkinson's disease suffer from sleep disturbances. The molecular mechanisms uncovered in fruit flies and human stem cells also ...

Drugs that suppress immune system may protect against Parkinson's

May 31, 2018
People who take drugs that suppress the immune system are less likely to develop Parkinson's disease, according to a study from Washington University School of Medicine in St. Louis.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.