Associate Editor, MedPage Today
Some successes but not enough to justify pursuing this approach
SAN DIEGO -- About a quarter of Parkinson's disease patients were able to come off levodopa
(L-Dopa) after dopamine-producing fetal cells were transplanted directly into their brains, but
the technology is unlikely to advance given several challenges, researchers reported here.
Curt Freed, MD, of the University of Colorado, and colleagues transplanted 61 patients from
1988 to 2000, without using any immunosuppressive drugsBut 95% to 98% of transplanted neurons died within days of the transplant, and obtaining fetal tissue is a challenge -- it comes from aborted fetuses and only 1 in 40 provide sufficient material, Freed told MedPage Today at the Society for Neuroscience meeting here.
"The way forward will be with embryonic stem cells and induced pluoripotent stem cells," said Freed, who acknowledged that these cells come with their own challenges, including getting the recipe exactly right and carrying a risk of malignancy in the long run.
During the meeting, Freed presented results on 16 patients who died 7 months to 27 years after their transplants and for whom post-mortem brain studies were possible.
Generally, the transplants produced healthy dopamine-producing neurons in all of the brains, with normal development in most, making connections with other neurons in areas outside of the transplant region. The cells were inserted directly into the putamen using a needle injection, Freed said.
The immune system didn't destroy these cells, even without immunosuppression, he reported.
Freed focused on two patients, one of whom had the longest transplant survival at 27 years, receiving it at age 52 and living until 79. The neurons lasted the entire time, Freed said.
Another male patient who had the transplant at 75 and died at age 85 was able to stop levodopa entirely and had the largest number of surviving cells seen from any transplant, "so age isn't a factor," Freed said.
Although 25% of patients were able to stop levodopa, Freed noted that the transplant is "no better than the best drugs ... and does not slow the progression of the disease."
He said there were few adverse effects, although there is "always the risk of brain hemorrhage at the time of surgery," noting that one of the 61 patients had a severe stroke during the surgery an died a month later as consequence of that stroke.
Dyskinesia was also common, with about 15% of patients being permanently dyskinetic even after stopping levodopa.
While other groups have performed fetal dopamine neuron transplants -- including 18 patients in Sweden and 25 at the University of South Florida, Freed said -- it's unlikely that the technology will go forward.
"My perspective is that we learned everything we needed to know about the transplant, that it can survive, we don't need to immunosuppress patients, we can replace levodopa, but it's not a solution for Parkinson's and it doesn't stop progression," Freed said.
Procedures using embryonic stem cells and induced pluoripotent stem cells could open the treatment to vastly more Parkinson's patients, Freed said, noting that his team is currently at work on those models: "We are making these cells, but the challenge is how good they are. There is great variability."
http://www.medpagetoday.com/MeetingCoverage/SFN/61482
After was running around from doctor to doctor before we finally get rid of her PD ,at age 74 my mother noticed that her handwriting was getting smaller and I was writing faster as well. She also noticed a small tremor in her left hand. The doctor went over her different symptoms and he suspected she either had a small stroke or the beginnings of Parkinson 's disease. After finding a neurologist and some testing she was diagnosed with the beginning stages of Parkinson’s disease. That was 3 years ago. She take Sinimet four times a day to control the symptoms, which include falling, imbalance, gait problems, swallowing difficulties, and slurring of speech,This year, our family doctor started her on multivitamincare. org PD Herbal mixture, 15 weeks into treatment she improved dramatically. At the end of the full treatment course, the disease is totally under control. No case of dementia, hallucination, weakness, muscle pain or tremors.
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