The latest results from a trial in which five Huntington's disease (HD) patients received fetal nerve tissue transplants show that the treatment can slow, but not stop the progression of the condition. The study, carried out at the Henri Mondor Hospital in France, shows that for some patients, cell transplants could provide a few years of improvement. But the effect is temporary, say the team, who published their results in the journal Lancet Neurology.
HD is a genetic condition that causes progressive damage in certain areas of the brain, leading to gradual physical, emotional and mental changes. Symptoms of HD usually appear between the ages of 30 and 50 years, and people with the disease have a 50 per cent chance of passing it on to each of their children. Although currently incurable, scientists think HD could potentially be treated with injections of healthy cells, since it is limited to specific brain areas.
In 2000, the French team reported that three of five HD patients who had received grafts of fetal nerve cells showed an improvement two years after the treatment. However, the latest follow-up study of these individuals show that these improvements 'plateaued' after two years, and the patients began to decline again over the next 2-4 years. The researchers say the study show the treatment is 'not a permanent cure' for HD, but offers a period of remission.
One patient was still working part-time six years after the treatment, and all three regained skills they had lost before the surgery - including cycling and being able to carry out household chores. However, other skills, such as guitar playing, were lost again by five years after the treatment. A spokeswoman for the UK Huntington's Disease Association said: 'we welcome any advance if people can be helped', but cautioned 'this is major brain surgery and there are risks'.
Six to eight fetuses are required to provide enough brain cells for each operation, which are obtained from consenting women undergoing abortions. A similar approach using laboratory-grown stem cells could one day be used to treat HD, as well as other degenerative brain disorders like Parkinson's disease.