Alternative to Embryonic Stem Cells.("multipotent adult progenitor cells" from bone marrow)

Thanks to research coming out of the University of Minnesota's Stem Cell Institute, what had seemed to be a logjam in the debate over both cloning and embryonic stem cell research that requires the destruction of human embryos may have been broken.

Dr. Catherine M. Verfaillie and her colleagues have discovered a type of adult stem cell found in bone marrow that holds out the possibility of growing into any kind of tissue in the body.

The work of Dr. Verfaillie and her colleagues is part of a broader pattern of recent discoveries which challenge the conventional wisdom - - that because stem cells found in human embryos are "unspecialized," they have a monopoly on the ability to become any tissue type found in the human body.

Dubbed "multipotent adult progenitor cells" (MAPCs), the adult stem cells isolated by Dr. Verfaillie's team appear to offer the best of all possible worlds. They seem to possess all the advantages attributed to embryonic cells but avoid the two major drawbacks researchers have encountered with embryonic stem cells: (1) Coming from the patient's own body, the immune system would not attack the tissue as foreign invaders; and (2) the MPACs don't turn cancerous!

As reported first in the November 1, 2001, edition of the journal Blood and then amplified in a piece that appeared January 26 in the journal New Scientist, Verfaillie et al. have shown that MAPCs can be coaxed into turning into muscle, bone, liver, cartilage, and a variety of types of neurons and brain cells. In addition, at least in the lab, these cells went about their business without showing any signs of slowing down. (According to the Boston Globe, "MAPCs express an enzyme called telomerase that keeps cells from aging.")

"The work is very exciting," said Ihor Lemischka of Princeton University. Irving Weissman of Stanford University said, "It's very dramatic the kinds of observations Verfaillie is reporting. The findings, if reproducible, are remarkable."

Even Rudolph Jaenisch of MIT, a vocal proponent of research that requires the destruction of human embryos to obtain their stem cells, admitted to the New York Times, "I haven't seen the data, but if they did it, that's pretty good."