Stem cell surgery, in which stem cells from a patient’s body are transplanted into some other part of the body, is gaining in popularity. One patient in Los Angeles found out the hard way that the surgery is largely untested and unregulated. Stem cells are sometimes used for anti-aging purposes, the idea being that they’ll turn into brand-new tissue and help heal aging cells nearby. But her doctors also used a dermal filler largely made of calcium hydroxylapatite, which happens to trigger stem cells to turn into…well, bone, rather than new tissue. The woman is recovering nicely, but it’s a really fascinating story of how powerful and potent stem cells are–and how we need to be careful with how we use them in these early stages of stem cell use. Scientific American
