Brain imaging (FP-CIT-PET) image suggesting transplanted dopamine cell engraftment. Compared to the left side before transplantation (baseline), the increase in image signal (dotted line) after 1 year on the right side is evident. Severance Hospital
Mr. A, a man in his 50s who has suffered from Parkinson’s disease for over 10 years, has been receiving dopamine medication, but his symptoms have gotten worse. ‘Frozen gait (a symptom in which the feet momentarily stop while walking as if their feet are frozen to the ground)’, which is common among Parkinson’s disease patients, has made it difficult to go to the bathroom alone. However, after receiving an embryonic stem cell transplant last year, these symptoms almost disappeared. I was able to walk for about an hour a day and play table tennis and badminton.
The clinical research team of Professor Lee Pil-hyu of the Department of Neurology at Severance Hospital and Professor Jin-woo Jang of Neurosurgery at Korea University Anam Hospital announced on the 12th that they had dramatically improved the symptoms of patients with Parkinson’s disease, an incurable disease, by administering a treatment using embryonic stem cells.
Parkinson’s disease is a disease in which dopamine neurons in the brain die, causing problems with motor control. It occurs mainly in middle-aged people. Most people receive drug treatment to relieve symptoms by replenishing dopamine that is lacking due to neurodegeneration or enhancing the effects of dopamine. Dopamine drug treatment generally improves symptoms in the beginning, but as time goes by, the effectiveness of the drug decreases and side effects often occur.
The research team differentiated embryonic stem cells into ‘neural progenitor cells’ (cells in the stage before growing into nerve cells) that secrete dopamine and then injected them into the brains of 12 Parkinson’s disease patients. Like Mr. A, patients aged 50 to 75 who had suffered from Parkinson’s disease for more than 5 years after being diagnosed were eligible only for patients who were less effective in existing dopamine drug treatment or who showed symptoms such as freezing of gait.
The research team measured symptom changes in each patient group one year after receiving low dose (3.15 million cells) and high dose (6.3 million cells) among the total 12 subjects. On the Hohenya scale, which classifies Parkinson’s disease symptoms into stages 1 to 5 according to severity, an average of 19.4% (stage 3.7 – 3) of low-dose recipients improved. In those receiving high doses, the average improved by 44.4% (stage 3.7 -> stage 2). The research team explained, “The level of improvement in patients who received high doses improved from a severe state to an early stage of the disease.”
In the Parkinson’s Assessment Scale, which evaluates objective motor performance, those who received low doses improved by 22.7% and those who received high doses improved by 25.3%. The symptom of freezing gait completely disappeared in one of the two low-dose recipients, and completely disappeared in three high-dose recipients (100% improvement). This means recovery to normal. For some recipients, the Parkinson’s Rating Scale significantly improved by 40.7% after one year.
As a result of dopamine brain imaging, the brain area that secretes dopamine was noticeably enlarged. The research team explained, “This is because the dopamine neural precursor cells injected into the brain grew into nerve cells that secrete dopamine.”
No unusual side effects related to cell transplantation were observed in any patient. Of the 12 people who have received transplants to date, one person had mild bleeding in an area not directly related to the transplant site, but no abnormal symptoms or side effects were observed. The research team plans to follow up and monitor progress for up to two years after transplantation.
Professor Kim Dong-wook of the Department of Physiology at Yonsei University College of Medicine, the developer of the treatment, said, “The cell therapy we developed uses human embryonic stem cells, so it is not only effective in treating Parkinson’s disease, but also reduces typical side effects such as freezing of gait and loss of drug efficacy,” adding, “Parkinson’s disease.” “As a patient who had suffered for a long time started enjoying badminton and walking after receiving the treatment, this fundamental treatment will contribute to helping patients regain a healthy life,” he said.
