Adult Stem Cell Shown to Have Same Versatility Once Claimed Only for Embryonic Stem Cells

Date: 07/20/2002

“The claim that there are alternatives to using stem cells derived from embryos is not, at the present time [9/99] supported scientifically. We recognize, however, that this is a matter that must be revisited continually as the demonstration of science advances.”

— “Ethical Issues in Human Stem Cell Research,” National Bioethics Advisory Commission, September, 1999 (emphasis added).

Dr. Catherine Verfaillie and her team at the University of Minnesota have now published peer-reviewed evidence for the ability of an adult bone marrow stem cell to proliferate extensively in culture and form virtually any tissue type – properties once claimed exclusively for embryonic stem cells.

Earlier this year (1/26/02), reporting on Verfaillie’s research, New Scientist said her team had discovered what might be “the most important cell ever,” capable of producing any tissue in the body. “If so,” the New Scientist continued “there would be no need to resort to therapeutic cloning.” These stem cells were dubbed “Multipotent Adult Progenitor Cells” (MAPC’s). Since then, the team has produced several reports on the MAPC’s, including their isolation from rodents and humans, their growth abilities, and their capacity to transform into various other tissues including blood vessels, nerves, and liver.

The evidence in this latest paper, published in Nature, invalidates all of the previous work and provides definitive proof for the abilities of the MAPC’s to proliferate and form any tissue in the body:

  • The MAPC’s could be grown in culture over 120 generations – more than twice the number previously thought possible for adult stem cells – without losing their capacity to differentiate into other tissues.
  • The MAPC’s could be directed in culture to form specific tissues from each of the three “primary germ layers”, which are the three main developmental types of tissues –an indication that the cells can potentially form any tissue. When injected into mice, the cells participated in formation of various tissues including blood and marrow, liver, lung, and gut.

The MAPC’s thus show the potential to do everything proposed clinically for cloning and embryonic stem cells, yet without tumor formation, and with the ability to use the patient’s own cells to overcome the problem of immune rejection. The authors note: “As MAPC’s proliferate extensively without obvious senescence [aging] or loss of differentiation potential, they may be an ideal cell source for therapy of inherited or degenerative diseases.”

In what is considered the “gold standard” test for pluripotency (i.e. the ability to form any adult tissue) Verfaillie and her team put the adult bone marrow stem cells to the same test used to prove the pluripotency of mouse embryonic stem cells. The result showed that single MAPC cells injected into early mouse embryos could form most, if not all, of the tissues of the developing mice.

Do No Harm: The Coalition of Americans for Research Ethics is a national coalition of researchers, health care professionals, bioethicists, legal professionals, and others dedicated to the promotion of scientific research and health care which does no harm to human life. Do No Harm rejects the course of action taken by the National Institutes of Health, to support destructive human embryo stem cell research. Instead, our government should promote adult stem cell research which protects the inviolability of all individuals, rejects harming some for the potential benefit of others, and holds as much, if not more promise, for medical progress.