A part of the placenta called the amnion, or the outer membrane of the amniotic sac, is comprised of cells that have strikingly similar characteristics to embryonic stem cells, including the ability to express two key genes that give embryonic stem cells their unique capability for developing into any kind of specialized cell, the researchers report. And according to the results of their studies, these so-called amniotic epithelial cells could in fact be directed to form liver, pancreas, heart and nerve cells under the right laboratory conditions.
"If we could develop efficient methods that would allow amnion-derived cells to differentiate into specific cell types, then placentas would no longer be relegated to the trashcan. Instead, we'd have a useful source of cells for transplantation and regenerative medicine," said senior author Stephen C. Strom, Ph.D., associate professor of pathology at the University of Pittsburgh School of Medicine and a researcher at the university's McGowan Institute for Regenerative Medicine.
According to U.S. census figures, there are more than 4 million live births each year. For each discarded placenta, the researchers calculate there are about 300 million amniotic epithelial cells that potentially could be expanded to between 10 and 60 billion cells relatively easily.
"Provided that research advances to the point that we can demonstrate these cells' true therapeutic benefit, parents could conceivably choose to bank their child's amniotic epithelial cells in the event they may someday be needed, as i