Surgeons in Zhengzhou, China, will soon begin the first clinical trial of embryonic stem cells (ESCs) in the world as they open the skulls of Parkinson’s patients and inject the ESCs into their brains. The goal for the 4 million or so immature embryonic neuron cells to treat the debilitating symptoms of the Parkinson’s disease. After the injections, the patients’ skulls will be closed up, and they will return home to wait and see if the treatment pans out.
A second medical team, also in Zhengzhou, will target age-related blindness caused by macular degeneration using ESCs. In that trial, the ESCs will hopefully replace lost retinal cells.
Both trials signal a new era in stem cell treatments and their regulation in China. Before 2015, China lacked a clear regulatory framework in this area, and this led to various unproven treatments making use of stem cells popping up on the market. The country’s researchers hope to solve this problem through these new regulations and groundbreaking clinical trials like these two.
“It will be a major new direction for China,” Beijing Institute of Transfusion Medicine stem-cell scientist Pei Xuetao told Nature. Xuetao’s position is no surprise, since he is on the central-government committee that approved the trials.
However, the scientific community isn’t entirely unified in its support of the trials, and not everyone is convinced that they will be successful. Scripps Research Institute stem cell biologist Jeanne Loring said she thinks the choice of cell in the Parkinson’s disease trial is not specialized enough to achieve the intended results. “Not knowing what the cells will become is troubling,” Loring told Nature.
Memorial Sloan Kettering Cancer Center stem-cell biologist Lorenz Studer, who has years of experience characterizing these kinds of neurons in advance to prepare for clinical trials of his own, told Nature that “support is not very strong” for the use of precursor cells. “I am somewhat surprised and concerned, as I have not seen any peer-reviewed preclinical data on this approach,” he said.
However, the Chinese research team is confident about their plans. Chinese Academy of Sciences Institute of Zoology stem cell specialist Qi Zhou, who is leading both ESC trials, said that the animal trials conducted thus far have been promising. “We have all the imaging data, behavioral data, and molecular data to support efficacy,” Zhou told Nature.
If Zhou and the rest of the team is correct, this will represent a major step forward for the entire world and usher in a new era of stem cell research.