Cell therapy holds promise as a new treatment for Parkinson’s disease, but in many trials to date, most transplanted dopamine cells have failed to survive, raising a fundamental obstacle. Recent advancements led by researchers at McLean Hospital and Massachusetts General Hospital could change this.
- Researchers at McLean and Mass General Hospital demonstrated that a transplant surgical procedure triggers a profound immune response (called “needle trauma”) and causes the death of most grafted dopamine neurons
- They also found that co-transplantation of neuronal cell therapy with host regulatory T cells resulted in effective suppression of needle trauma and significant improvement in the survival and recovery of grafts
- Findings suggest a path for the “realistic” use of cell therapy to treat neurodegenerative disorders
Investigators used regulatory T cells to supplement neuronal cell therapy and decrease adverse effects of the surgical procedure in rodent models. Results from the team are published in Nature.
“We have been investigating personalized, stem-cell based therapies that reprogram a patient’s own cells to treat their Parkinson’s,” said corresponding author Kwang-Soo Kim, PhD, director of the Molecular Neurobiology Laboratory at McLean.
“We have now made a major breakthrough using immune cells to improve delivery, survival, and recovery for neuronal cell therapies,” continued Kim. “Our findings show the power and flexibility of cell therapy to be modified and enhanced to become a realistic modality to treat conditions like Parkinson’s.”
In the United States, only Alzheimer’s disease is a more common neurodegenerative disorder than Parkinson’s disease, which is characterized by loss of midbrain dopaminergic neurons. The current standard of care is dopamine replacement therapy, which addresses only symptoms like tremors or stiffness and has substantial side effects.
Since the 1980s, cell therapies have faced a significant barrier: poor graft survival. Researchers have proposed diverse mechanisms to explain the cell death and have added various modifications to improve cell survival.
Three years ago, Kim’s team demonstrated that personalized cell therapy could be used to replace dopamine neurons in the first personalized cell therapy in a sporadic Parkinson’s disease patient. However, their results were restricted to a single patient, and limited graft survival remained a key challenge.