A rogue surgeon injects stem cells from a fetus into a sick man’s brain. The cells morph and form body parts. When the man dies, the pathologist finds cartilage, skin and bone clumped in his brain. The scene is not from a horror movie; it happened to Max Truex, a former Olympic runner who suffered from Parkinson’s disease. The case sent a chill through the scientific community when it came to light 15 years ago and typifies some of the hurdles researchers have faced while trying to bring stem cell therapies to the market.
