Over at h+, Dr. Terry Grossman describes a procedure he recently underwent in Mexico in which placental tissue was implanted beneath his skin. He hopes stem cells from the tissue will “hone in on areas of the body in need of repair.” Dr. Grossman also describes several unique properties of placental stem cells when compared to adult stem cells or even embryonic stem cells.
Embryonic cells are controversial because a life (or a potential life, depending on your point of view) is destroyed in obtaining them. They are desirable because they don’t have any antigens on their cell surfaces, so they won’t be rejected by anyone who receives them, and also because they are totipotent, meaning they have the ability to turn into any type of cell in the body. The downside to embryonic cells is that they are very difficult to control and their practical value still lies in the future.
Adult stem cells, on the other hand, do have practical applications even in the United States today. They are being used in several clinical trials with surprisingly beneficial results, and as treatments for patients with otherwise incurable conditions in many other regions of the world. Advantages of adult stem cells are that they are easier to work with and easily obtained from the bone marrow.
And:
Placental stem cells are similar to umbilical cord blood cells, but they are even more “user friendly” as they combine advantages of embryonic stem cells with those of adult cells. They have relatively weak antigens on their surfaces so they can be used in a wide spectrum of potential recipients and they are multipotent, like adult cells, so they are relatively easy to control.
While Dr. Grossman hasn’t noticed any beneficial effects from the transplants in the first two weeks since the procedure, I’ll be quite interested to hear more about his experience.