Scientists Turned Parkinson's Disease Patient's Skin Cells Into Brain Cells, Now He Can Tie His Shoes Again

Scientists have helped a man with Parkinson's disease swim, ski and tie his own shoes again by reprogramming his skin cells and implanting them inside his brain.

The team at McLean Hospital, Massachusetts, and Massachusetts General Hospital (MGH) took the skin cells of a 69-year-old patient with the degenerative disorder and turned them into what are known as pluripotent stem cells, which can develop into almost any type of cell in the adult body. The stem cells were tweaked to become dopaminergic neurons. These die off in people with Parkinson's disease. The findings were published in the New England Journal of Medicine.

To check the cells wouldn't be rejected by the man's body, the researchers first grafted them on to the brains of lab mice and looked for signs of immune system response.

Next, they developed an implanting technique involving a syringe to insert the cells into his brain. They used the approach in two first-of-their-kind surgeries in 2017 and 2018, according to a press release from McLean Hospital. In two surgeries focused on either side of the brain separated by six months, surgeons placed a total of eight million dopaminergic neurons inside the patient's brain. The doctors had to seek special permission from the U.S. Food and Drug Administration (FDA) to carry out the procedures.

As the cells were his own, unlike during traditional transplants the man wasn't given drugs such as immunosuppressants.

An estimated 1 million people in the U.S. and 10 million worldwide are living with Parkinson's disease, according to the American Parkinson Disease Association. The condition can cause tremors, slow a person's movements and impair their posture and balance. A patient may also see their speech and writing change, and struggle with automatic movements like blinking, smiling and moving their arms when they walk. There is currently no way to slow its progression.

The patient struggled with tremors, problems with his posture, and fine motor control. Periodic neurological examinations every few months after his surgeries were used to chart whether his symptoms improved, and brain scans checked for signs of tumors, strokes or hemorrhages.

At 18- and 24-month checkups after his surgeries, respectively, the man had not suffered any adverse effects or seen his function decline. He was able to reduce the drugs he was taking to replace dopamine by 6 percent.

The man's walking and speech have improved. He has also ridden a bike, and taken up skiing and swimming for the first time years. The dopaminergic neurons appear to be working correctly, releasing dopamine and connecting to other neurons in his brain, and haven't been rejected by the patient's immune system. Improvements were more clear in the right side of his brain than the left, for reasons that aren't clear.

Kwang-Soo Kim, co-author of the study and director of the Harvard Medical School-affiliated Molecular Neurobiology Laboratory at McLean Hospital, said in a statement: "Current drugs and surgical treatments for Parkinson's disease are intended to address symptoms that result from the loss of dopaminergic neurons, but our strategy attempts to go further by directly replacing those neurons."

Kim explained: "Because the cells come from the patient, they are readily available and can be reprogrammed in such a way that they are not rejected on implantation. This represents a milestone in 'personalized medicine' for Parkinson's."

Dr. Jeffrey Schweitzer, co-author, specialist Parkinson's neurosurgeon and director of the Neurosurgical Neurodegenerative Cell Therapy program at MGH, told Newsweek: "Personalized cell therapy is complex because it is tailored to just one patient. That meant we had to extensively test the patient's cells to confirm that they were safe for implantation, and that we also underwent a rigorous regulatory review by the FDA and our Institutional Review Board. With perseverance over several years and building on the strong foundation in Dr. Kim's laboratory, we were able to achieve this goal."

However, the team cautioned the improvements should be interpreted with caution as the research breaks with some conventions of clinical trials. Both he and the team were aware he was having the surgery, meaning it wasn't a randomized treatment, which could bias the results, and there were also no control patients.

Dr. Bob Carter, co-author of the study and chief of Neurosurgery at Massachusetts General Hospital and co-senior author, told STAT News: "We didn't cure him of Parkinson's. I like to think we stabilized him."

Despite the positive results in the patient, Dr. Todd Herrington, co-author, neurologist at the MGH and Parkinson's expert, stressed more work is needed to prove it can work in others.

"As a neurologist, my goal is to make state-of-the-art treatments available to patients with Parkinson's," he said. "This is a first step in developing this therapy. Parkinson's patients should understand that this therapy is not currently available and there is a lot of work still required to prove this is an effective treatment."

Schweitzer told Newsweek: "The advantages of the approach, that the cells come from just one patient and are then transformed into the correct neuron cell type and transplanted back to that same patient, also confer complexity and expense compared to using one off-the-shelf standard cell line for all patients."

He said the study provides helpful guideposts for testing the treatment in others, and the team is working with the FDA to move a Phase 1 clinical trial study. "We anticipate that the general availability of this type of therapy, if it passes all the necessary rigorous tests, is still some years away."

The patient, a former doctor and businessman named George Lopez, gave the team $2 million to fund their work, STAT News reported. He told the website: "I don't think I'm courageous [to have the treatment first]," adding: "Though it's true, we didn't know if my head was going to blow up."

Recalling his diagnosis, Lopez said: "I became extremely depressed. Of all the people to be hit with Parkinson's disease, which locks you in your body like a prisoner, I felt, I shouldn't have been afflicted with it if there is any fairness in the universe. But of course, there isn't."

Professor David Dexter, associate director of research at the research and support charity Parkinson's UK who did not work on the project, told Newsweek: "As this treatment involved just one person, it is difficult to come to any conclusions about its true potential. There are also serious risks involved with any brain surgery."

Commenting more widely on such procedures, he said: "Stem cell-based therapies hold much promise for reversing Parkinson's, but currently, no therapy has been able to achieve this.

"These therapies have come a long way in the last decade and we are now trying to understand the potential short- and long-term benefits, and risk of these treatments for people with Parkinson's.

"Some of the earliest cell transplant therapies in Parkinson's date back to the 1980s, but subsequent trials showed mixed results. Some people did remarkably well, even coming off the medication they had relied on, while others experienced little to no improvements."

He concluded: "We still need to overcome significant hurdles to make stem cell-based therapies widely available. Questions around the time and cost of generating new cells from the individual being treated need answering. But with several ongoing, large-scale studies, the aim is to demonstrate that stem cell-based therapies can reverse Parkinson's."

Schweitzer concluded: "Parkinson's remains an incurable disease. I've done almost 1,000 surgeries of other types for Parkinson's patients, and our lead neurologist, Dr. Todd Herrington, has treated as many such patients with medications and deep brain stimulation.

He said replacing the cells that create dopamine in the brains of people with Parkinson's "was a very meaningful concept to me and to the entire team.

"While we were very inspired by our one patient who underwent the procedure, the real purpose of the work is to try to create a treatment for the many patients who suffer from Parkinson's."

This article has been updated with comment from Dr. Jeffrey Schweitzer.