Fetal cells injected into a man’s brain to cure his Parkinson’s
A man in his mid-50s with Parkinson’s disease had fetal brain cells injected into his brain last week. He is the first person in nearly 20 years to be treated this way – and could recover full control of his movements in roughly five years.
“It seemed to go fine,” says Roger Barker of the University of Cambridge, who is leading the international team that is reviving the procedure.
The treatment was pioneered 28 years ago in Sweden, but two trials in the US reported no significant benefit within the first two years following the injections, and the procedure was abandoned in favour of deep brain stimulation treatments.
What these trials overlooked is that it takes several years for fetal cells to “bed in” and connect properly to the recipient’s brain. Many Swedish and North American recipients improved dramatically, around three years or more after the implants – long after the trials had finished. “In the best cases, patients who had the treatment pretty much went back to normal,” says Barker.
After the fetal cells were wired up properly in their brains, they started producing the brain signalling chemical dopamine – low levels of this cause the classic Parkinson’s symptom of uncontrolled movements. In fact, the cells produced so much dopamine that many patients could stop taking their Parkinson’s drugs. “The prospect of not having to take medications for Parkinson’s is fantastic,” says James Beck of the Parkinson’s Disease Foundation in the US.
Because the early trials missed this improvement no one had received fetal brain cells since the 1990s. But the man treated at Addenbrooke’s Hospital in Cambridge on 18 May did not receive a full treatment, because the team only had enough cells to treat one half of his brain.
The transplant depends on fetal cell donations from women terminating pregnancies, so the researchers don’t know when cells are likely to be available. It takes cells from at least three fetuses to treat each half of the brain, and four earlier attempts to treat the same man had to be stopped due to a lack of cells.