Scientists from the Wake Forest University School of Medicine and Harvard Medical School have discovered a new source of stems cells which may be used to create muscle, bone, fat, blood vessel, nerve and liver cells in the laboratory: the amniotic fluid.

Atala and colleagues discovered a small number of stem cells in amniotic fluid -
estimated at 1 percent - that can give rise to many of the specialized cell types found in the human body. The scientists believe the newly discovered stem cells, which they have named amniotic fluid-derived stem (AFS) cells, may represent an intermediate stage between embryonic stem cells and adult stem cells. They have markers consistent with both cell types.

The cells were harvested from back-up amniotic fluid specimens used for prenatal amniocentesis. Considering that there are at least 100,000 specimens on storage, the scientists say that there is, in theory, enough to supply 99 percent of the U.S. population with perfect genetic matches for transplantation. The study was published in an advanced online edition of Nature Biotechnology (doi: 10.1038/nbt1274). For an overview, see the press release from the Wake Forest University School of Medicine.

[Photo: Medline Plus]