by Alok Jha
Scientists have found a new source of stem cells that does not involve destroying embryos. The cells can be harvested easily from the fluid surrounding developing babies in the womb and could help overcome ethical concerns.
It has been known for decades that the placenta and the amniotic fluid in the womb contain important cells. "We asked the question: is there a possibility that within this cell population we can capture true stem cells? The answer is yes," said Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest, who led the research.
Stem cells can grow into any type of body tissue and are used to research cures for conditions such as diabetes and brain disorders, including Alzheimer's and Parkinson's disease. It is hoped that one day they may be used to grow replacement tissue that is a perfect genetic match for patients with damaged organs.
Stem cells from embryos are highly prized because they are the most adaptable. They are hard to obtain, however, because they are normally harvested from embryos left over from fertility treatments. Anti-abortion campaigners argue this leads to destruction of human life. Adults also have stem cells, but these can turn into fewer types of body tissue.
Researchers said the newly discovered amniotic fluid-derived stem (AFS) cells represent an intermediate stage between embryonic and adult stem cells. They grew AFS cells into muscle, bone, fat, blood vessel, nerve and liver cells. "Our hope is that these cells will provide a valuable resource for tissue repair and for engineered organs as well," said Prof Atala. His results are published today in the journal Nature Biotechnology.
"These cells are capable of extensive self-renewal, a defining property of stem cells," he said. "They also can be used to produce a broad range of cells that may be valuable for therapy."