Embryonic-like cells repair damaged mouse hearts

By Rachel Stockton (rachels@foodconsumer.org)

A new study out of Mayo Clinic is verifying that scientists are one step closer to eliminating the controversial need to harvest stem cells from embryos just a few days post-fertilization.

Regenerative medicine refers to the use of stem cells as a "universal" cell that can morph into any of the 220 cells within the human body, repairing and regenerating damaged tissue.

In 2207, researchers in Tokyo and Wisconsin announced they had discovered a way to replicate embryonic stem cells from adult skin cells. These ordinary cells can be reprogrammed to behave like stem cells, becoming "blank slates" for use throughout the human body. The "engineered" stem cell is called an "induced pluripotent", or iPS, stem cell.

The Mayo study used iPS cells in mice that had suffered heart damage from cardiac arrest in an effort to regenerate damaged heart muscle. The tissue in the damaged muscle sends out "signals" for repair; iPS cells "hear" the call, and come to the aid of the distressed cells.

Two weeks after injecting the mice with iPS cells, their bodies created different types of tissue, muscle, blood vessels and cells that line blood vessels. They showed a marked improvement in heart function.

One of the biggest advantages of using the iPS cells is that it makes the controversy over creating and destroying embryos in an effort to harvest stem cells a moot point. By using a certain virus, scientists are able to turn back the clock on skin cells, creating blank slate, universal cells.

Theoretically, a patient in need of a transplant could use stem cells created from his own skin, radically reducing rejection risk. Dr. Thomas Nelson, lead researcher for the mice study, contends that even though it could take several years, the technology could be helpful to those who need heart transplant.