Jeffery Schweitzer, MD, PhD and lead author of the study elaborates on the research methods and hopes for stem cell technology in the future.
Researchers at McLean Hospital and Massachusetts General Hospital (MGH) have tested a stem cell treatment method that avoids rejection by the patient's body, a significant limitation of stem cell therapy. The experiment was only conducted in one Parkinson's patient, but researchers hope the results will open the door for a larger sample size.
Stem cells have not "differentiated," meaning they have not taken the form of a specific cell type, such as a skin cell or a nerve cell. Stem cells give rise to other undefined cells, which either become stem cells or differentiate. Over the past decade, the technology to use stem cells as personalized therapy has evolved rapidly. For example, in Multiple Sclerosis (MS) research, the hope is to swap out immune cells that are attacking the patient's own neurons with immune cells, grown from stem cells, that will not attack the neurons.
On May 13, 2020, MGH released the study taking stem cells from one patient's skin to replace his own dopaminergic neurons lost during his Parkinson's progression. Dopaminergic neurons produce the majority of the body's dopamine. Parkinson's is associated with tremor and a decline in fine motor skills because the nerve cells do not have enough dopamine to transmit signals between the muscles and the brain. This study differs from other stem cell research because stem cells typically originate from a bank of stem cells, not the patient's own body. Though cell banks have greater control over what characteristics the cells have, the patient's body often rejects the transplant.
So far, the 69-year-old patient has responded well to the stem cell transplant. His body accepted the stem cells, which have reproduced and matured into dopaminergic neurons. Researchers associated with the study say the results are encouraging but emphasize that it was only a single patient test.
The National Institute of Health, McLean Hospital, and MGH, primarily funded the study, but the patient at the center of the study also contributed to the funding. The researchers worked with the MGH Institutional Review Board to clear all ethical hurdles.