Stem cells offer epic possibilities—lab-grown organs, injections to erase catastrophic injuries and cures for everything from Alzheimer’s disease to blindness. As with any young science, misconceptions abound. So Discoveries asked Dhruv Sareen, PhD, director of the Cedars-Sinai Induced Pluripotent (don’t worry, we’ll explain that, too) Stem Cell Core Facility to separate myth from reality.

Reality: “I correlate the power of stem cells with the degree of horsepower in an engine,” Sareen says, comparing types of stem cells to classes of automobile.

• Sports Car: These supercharged models include embryonic stem cells and induced pluripotent stem cells (iPSCs). Scientists create the latter by reprogramming adult skin or blood cells (told you we’d get to it).  Powerful as a Ferrari, these beasts can differentiate into all types of body cells—from kidney to bone.
• Muscle Car: Mesenchymal stem cells, usually taken from bone marrow, are like a stylish Mustang. These high-performance rides can produce a somewhat limited category of cells, including blood cells, cartilage and bone.
• Luxury Sedan: Adult stem cells can replace themselves—such as a cardiac cell begetting heart tissue—but lack the horsepower to differentiate into other cell types.

Reality: “People tend to think stem cell injections will completely replace missing or damaged cells. Not so,” Sareen says.

The main activity of most stem cell injections is to suppress immune reaction, providing temporary relief, but not a cure, for conditions like joint pain. Sareen cautions against clinics advertising injections as a cure-all, as most stem cell transplants are only available in Food and Drug Administration-approved clinical trials.

Reality: iPSCs have almost eliminated the need for embryonic stem cells in the lab.

“An advantage of iPSCs is that you can make a cell line of limitless supply that can be turned into any individual- and organspecific cell. All we need is a blood sample to make them—and then that patient doesn’t need to worry about tissue rejection,” Sareen says, though he notes their safety for clinical use is still being tested.

Reality: It’s like earthquake insurance. If affordable, it can’t hurt to bank cord blood after birth, but it will likely go unused.

However, for those with a family history of blood diseases, storing cord blood is a good idea. “Cord blood is the purest raw material source to create induced pluripotent stem cells, because a newborn hasn’t lived life and seen stress and L.A. smog. Therefore, gene mutations haven’t accumulated,” Sareen says.

The next generation of medicine will arrive courtesy of a combination of genetic engineering and powerful cell therapy, Sareen predicts. He points to a new form of cancer immunotherapy known as CAR T-cell therapy, in which a patient’s immune cells are reprogrammed to attack their disease.

“The knowledge we are gathering now eventually may help us eliminate cancers and regenerate organs,” he says.