Regenerative Medicine and Stem Cells Technologies

Scientists in China have demonstrated that embryonic stem cells (ESCs) partially alleviated the symptoms of Parkinson’s disease in monkeys. They published their findings in Stem Cell Reports. Parkinson’s disease is a neural degenerative disorder primarily caused by the death of dopaminergic neurons in the substantia nigra of the brain. Although ESCs have been proposed as a therapy for Parkinson’s disease, there has been a lack of preclinical studies demonstrating their safety and efficacy, especially in vivo. In this study, a research team led by Professor Zhou Qi and Professor Hu Baoyang from the Institute for Stem Cell and Regeneration of the Institute of Zoology within the Chinese Academy of Sciences, undertook a two-year evaluation of the safety and efficacy of dopaminergic neurons derived from ESCs in monkeys. The researchers first infused the monkeys with a neurotoxin to mimic the effects of Parkinson’s disease. At the same time, dopaminergic neurons were produced under current good manufacturing practice (cGMP) conditions using clinical grade human ESCs. After undergoing strict quality tests, these cells were transplanted into the brains of neurotoxin-induced Parkinson’s disease monkeys. After nine months, the monkeys were euthanized for analysis. The researchers used imaging methods combined with immunohistochemical evaluation and blood biochemical tests to demonstrate that the implanted cells did not exhibit excessive proliferation or tumor formation. Further study showed that the implanted cells had survived and further matured in vivo. Importantly, the researchers reported that there was no immune rejection of the cells or other serious adverse events. The human ESC grafts produced variable but apparent behavioral improvement for at least 24 months in most monkeys, indicating that clinical-grade human ESCs can serve as a reliable source of cells for Parkinson’s disease treatment. Their findings provide strong preclinical support for China’s first ESCs-based Phase I/IIa clinical study on Parkinson’s disease.

Reference:https://www.cell.com/stem-cell-reports/fulltext/S2213-6711(18)30227-3