“Our hope is that these cells will provide a valuable resource for tissue repair and for engineered organs,” said Anthony Atala, M.D. He is director of the Institute for Regenerative Medicine at Wake Forest.
It was already known that the placenta and amniotic fluid contained many cell types that can develop into fat, bone, and muscle, Atala said.
So he and his colleagues asked a question. “Is there a possibility that within this cell population we can capture true stem cells?”
The answer, they now know, is yes. Atala and his colleagues discovered a small number of stem cells in amniotic fluid – around 1%. They have named them amniotic fluid derived stem cells, or AFS cells for short.
These stem cells can generate many of the specialised cells found in the human body. The researchers believe AFS cells are an intermediate stage between embryonic stem cells and adult stem cells.
“It took this long to verify that we had a true stem cell,” said Atala. He began the work seven years ago.
“These cells are capable of extensive self-renewal, a defining property of stem cells. They can be used to produce a broad range of cells that may be valuable for therapy."
A big advantage of AFS cells is that they are easy to obtain.
The report describes how the cells were harvested from backup amniotic fluid specimens. These had been obtained for amniocentesis, a procedure that looks for genetic disorders before a baby is born.
Similar stem cells were isolated from “afterbirth”. This is the placenta and other membranes that are expelled after a baby is born normally.
The potential of stem cells is enormous. In principle a bank of just 100,000 specimens could supply 99% of the US population with perfect genetic matches for transplants, Atala says. There are more than 4 million live births each year in the United States.
Besides being easily obtained AFS cells can be grown in large quantities. This is because the cells divide in two every 36 hours.