Embryonic stem cells were first isolated in 1998 at the University of Wisconsin from embryos made in fertility clinics. They are useful to scientists because they can be grown in the lab and, in theory, be coaxed to form any of the 200 or so cell types in the human body, prompting attempts to restore vision, cure diabetes, and reverse spinal cord injury.
However, there is still no medical treatment based on embryonic stem cells, despite billions of dollars’ worth of research by governments and companies over two and a half decades. BlueRock’s study remains one of the key attempts to change that.
And stem cells continue to raise delicate issues in Germany, where Bayer is headquartered. Under Germany’s Embryo Protection Act, one of the most restrictive such laws in the world, it’s still a crime, punishable with a prison sentence, to derive embryonic cells from an embryo.
What is legal, in certain circumstances, is to use existing cell supplies from abroad, so long as they were created before 2007. Seth Ettenberg, the president and CEO of BlueRock, says the company is manufacturing neurons in the US and that to do so it employs embryonic stem cells from the original supplies in Wisconsin, which remain widely used.
“All the operations of BlueRock respect the high ethical and legal standards of the German Embryo Protection Act, given that BlueRock is not conducting any activities with human embryos,” Nuria Aiguabella Font, a Bayer spokesperson, said in an email.
The idea of replacing dopamine-making cells to treat Parkinson’s dates to the 1980s, when doctors tried it with fetal neurons collected after abortions. Those studies proved equivocal. While some patients may have benefited, the experiments generated alarming headlines after others developed “nightmarish” side effects, like uncontrolled writhing and jerking.
Using brain cells from fetuses wasn’t just ethically dubious to some. Researchers also became convinced such tissue was so variable and hard to obtain that it couldn’t become a standardized treatment. “There is a history of attempts to transplant cells or tissue fragments into brains,” says Henchcliffe. “None ever came to fruition, and I think in the past there was a lack of understanding of the mechanism of action, and a lack of sufficient cells of controlled quality.”
Yet there was evidence transplanted cells could live. Post-mortem examinations of some patients who’d been treated with fetal cells showed that the transplants were still present many years later. “There are a whole bunch of people involved in those fetal-cell transplants. They always wanted to find out—if you did it right, would it work?” says Jeanne Loring, a cofounder of Aspen Neuroscience, a stem-cell company planning to launch its own tests for Parkinson’s disease.