In a remarkable medical breakthrough, scientists from Harvard and Wake Forest report that they have discovered a new source of stems cells that have the ability to create muscle, bone, fat, blood vessel, nerve, and liver cells in the laboratory. These newly discovered stem cells, which they have named amniotic fluid-derived stem (AFS) cells, may represent an intermediate stage–“halfway houses”–between embryonic stem cells and adult stem cells. The research, which has been ongoing for the past seven years, was reported in yesterday’s Nature Biotechnology.
One of the primary advantages of the AFS cells is their ready availability. The cells can be harvested from backup amniotic fluid specimens obtained for amniocentesis or from “afterbirth,” the placenta and other membranes that are expelled after delivery. Anthony Atala, M.D., senior researcher and director of the Institute for Regenerative Medicine at Wake Forest University School of Medicine, says that a bank with 100,000 specimens theoretically could supply 99 percent of the U.S. population with perfect genetic matches for transplantation.
A number of factors make these cells preferable to embryonic stem cells (ESC), which have never been used for therapies. Their value could even potentially surpass adult stem cells, which are used in about seventy treatments and therapies. According to the report:
- The AFS cells can be grown in large quantities because they typically double every 36 hours.
- They do not require guidance from “feeder” cells.
- Unlike ESC, they do not produce tumors.
- The specialized cells generated from the AFS cells included all three classes of cells found in the developing embryo.
Because of their high degree of flexibility and growth potential, the AFS cells resemble embryonic stem cells. “The full range of cells that AFS cells can give rise to remains to be determined,” said Atala. “So far, we’ve been successful with every cell type we’ve attempted to produce from these stem cells. The AFS cells can also produce mature cells that meet tests of function, which suggests their therapeutic value.”
As with all stem cell research, we must be careful not to overstate either the promise or potential for producing a broad range of therapeutic uses. Nevertheless, it is encouraging to see empirical evidence for research that has, unlike ESCR, actual potential for developing cures.
Compare embryonic stem cells with amniotic fluid-derived stem cells:
ESC: Requires destruction of a human embryo to obtain cells.
AFS: Obtaining cells is ethically unproblematic.
ESC: If genetic matches for transplantation could be obtained at all, it would come from the creation and destruction of cloned human embryos.
AFS: Genetic matches for transplantation can be obtained from discarded placentas.
ESC: Therapeutic uses impeded because they are tumorigenic.
AFS: Do not produce tumors.
Even if we ignore the ethics of cloning and embryo destruction, this last reason is enough to prefer AFS to ESC. As James Sherley, an associate professor of biological engineering at MIT, notes, “[F]iguring out how to use human embryonic stem cells directly by transplantation into patients is tantamount to solving the cancer problem.”
This week the Democrats in Congress will again push for federal funding of embryonic stem cell research. However, unless we first discover a cure for cancer and find a way to harvest the millions of human eggs that will be needed for cloning, such research will remain nothing more than unethical science fiction. The only people who should support such research are the biotech firms who, unable to entice private investors, must line their pockets with the blood money of taxpayers. The rest of us, however, should push for funding of research that is both ethical and likely to produce therapeutically useful results. Those of us who believe in the value of both science and morality should remain in the real “reality-based community” and let the House Democrats march off alone into their Brave New World.
Newsweek: New Stem-Cell Source Could Alter Debate
New Scientist: ‘Ethical’ stem cells that arrive with baby
New Scientist: Cancer warning over stem cell therapies