A biotech company has conducted a small-scale trial involving the implantation of lab-made neurons into the brains of 12 people with Parkinson’s disease. The implanted neurons are designed to produce dopamine, which is deficient in Parkinson’s patients, and early data suggests they may have survived and improved symptoms in some cases. MIT Technology Review reports:

The study is one of the largest and most costly tests yet of embryonic-stem-cell technology, the controversial and much-hyped approach of using stem cells taken from IVF embryos to produce replacement tissue and body parts. The replacement neurons were manufactured using powerful stem cells originally sourced from a human embryo created an in vitro fertilization procedure. According to data presented by Henchliffe and others on August 28 at the International Congress for Parkinson’s Disease and Movement Disorder in Copenhagen, there are also hints that the added cells had survived and were reducing patients’ symptoms a year after the treatment.

These clues that the transplants helped came from brain scans that showed an increase in dopamine cells in the patients’ brains as well as a decrease in “off time,” or the number of hours per day the volunteers felt they were incapacitated by their symptoms. However, outside experts expressed caution in interpreting the findings, saying they seemed to show inconsistent effects — some of which might be due to the placebo effect, not the treatment. Because researchers can’t see the cells directly once they are in a person’s head, they instead track their presence by giving people a radioactive precursor to dopamine and then watching its uptake in their brains in a PET scanner.

“It is encouraging that the trial has not led to any safety concerns and that there may be some benefits,” says Roger Barker, who studies Parkinson’s disease at the University of Cambridge. But Barker called the evidence the transplanted cells had survived “a bit disappointing.”

He said the results were not so strong, adding that it’s “still a bit too early to know” whether the transplanted cells took hold and repaired the patients’ brains.

Originally Posted at https://slashdot.org/