A recent article in US News and World Report gives an account of the first patient to have reprogrammed cells successfully implanted in his brain.
The patient’s doctors reported that before the transplant the patient’s condition had been rapidly deteriorating. Currently, at the two-year mark, the deterioration is no longer evident. In fact, some symptoms have either stabilized or improved. The patient has not exhibited any adverse events.
The experiment was conducted by Dr.Kwang-Soo Kim, a senior researcher, and his team at McLean Hospital, a Harvard affiliate in Belmont, Massachusetts. Although the results have been modest, the experiment proves that the approach is feasible. Therefore, the team will be expanding the study to include additional patients.
A more detailed account of the procedure has been published in the May 14, 2020 issue of the New England Journal of Medicine.
About Parkinson’s Disease
The Parkinson’s Foundation estimates that there are approximately one million cases in the U.S.
The initial cause has not been determined, but with disease progression, the brain loses dopamine-producing cells. Dopamine regulates emotional responses and movement.
There are motion-related symptoms such as stiff limbs, tremors and problems with coordination. Other symptoms include irritability, depression, and skills that become progressively worse, such as a person’s thinking and memory skills. These effects may be somewhat lessened with medication but to date, no cure exists.
About the Procedure
The premise for the study was based on the team’s understanding that stem cells, due to their ability to grow into other types of cells in the body, could become a source of dopamine-producing cells in the brain.
The researchers developed induced pluripotent stem cells (iPSCs) that are taken from a patient’s blood or skin and reprogrammed back into a pluripotent state. The iPSCs are much like embryonic stem cells which can generate a significant amount of body tissue.
The iPSCs can create unlimited sources of human cells that can be used in therapeutic settings.
Some examples are
- the creation of new blood that is free of cancer to treat leukemia patients
- beta-islet cells to treat diabetics, and
- creating neurons that can benefit patients with neurological disorders
About the Patient
In this instance, the cells were taken from the 69 year-old patient’s skin and reprogrammed into iPSCs. Almost immediately after the procedure, the patient reported improvement in his quality-of-life.
The iPSCs were cultivated to be converted into dopamine-producing nerve cells (neurons) that were implanted into the patient’s brain.
A critical issue would have been the usual negative reaction of the immune system. It usually rejects anything entering the body that it deems to be a foreign substance.
But in this case, the cells were taken from the patient’s own skin. Therefore, his immune system tolerated the cells without the need to use drugs to suppress an immune response.
Two years after the transplant, imaging tests proved that the cells were alive and were functioning. The patient reported that his walking improved. He has also returned to some of his favorite sport activities.
Notes of Caution from the Parkinson’s Foundation
The Foundation’s chief scientific officer, although not involved in the research, commented that it is too soon to consider these cells as magic bullets. He said that even though current medications may ease problems with movement, they do not help non-movement issues. Also, will they eventually malfunction?
Dr. Kim agreed that more research is needed to determine what amount of dopamine-producing cells would be most effective and pinpoint the optimum time to intervene in the patient’s treatment.