University of Pittsburgh researchers have discovered that one type of cell in the human placenta has characteristics that are strikingly similar to embryonic stem cells in their ability to regenerate a wide variety of tissues.

The cells, called amniotic epithelial cells, potentially could be used to produce new liver cells to treat liver failure, or new pancreatic islet cells to cure diabetes or new neurons to treat Parkinson's disease.

Unlike embryonic stem cells, which are obtained only by destroying human embryos, these cells can be extracted from the same placentas that now are routinely discarded after birth. They thus could be a non-controversial alternative to embryonic stem cells.

"We think it would be easier to get these to the clinic than [embryonic stem] cells," said Stephen Strom, an associate professor of pathology at the Pitt medical school.

Not only do amniotic epithelial cells lack the controversy of embryonic stem cells, but they also do not generate the tumors associated with embryonic stem cells, he said. So it may be possible in some cases to simply transplant the amniotic cells to a patient, rather than to first grow the desired specialized cells in the laboratory.

Strom and Dr. Yoshio Miki, an instructor in the pathology department, described their discovery in a paper published online last night in Stem Cells Express; the paper also will appear in an upcoming issue of the journal Stem Cells.

Publication of the paper had been delayed while the university sought patent protection for the discovery, Strom noted. A local biotechnology company, Stemnion Inc., has licensed the patent rights from Pitt with plans to use the cells for treating cirrhosis and diabetes and to spur wound healing.