Scientists progress on livers, stem cells
Scientists at the University of Washington are optimistic that they've made what they call meaningful progress toward learning how to repair damaged human livers with stem cells.
If the experimental work continues successfully in the years to come, the technique could one day repair livers badly damaged by drug overdoses, hepatitis and alcoholism.
The UW research was reported in this week's edition of the Proceedings of the National Academy of Sciences.
"I think it's a significant first step," Dr. Nelson Fausto, chairman of the university's Department of Pathology, told The Seattle Times.
For the first time, a team of UW researchers, led by Fausto, isolated liver stem cells from human fetuses. The researchers grew them in the laboratory for months and infused them in laboratory mice, where they replaced thousands of dead liver cells.
The technique uses stem cells from aborted fetuses. So money for the research isn't covered by the ban on federal funding for work using stem cells taken from embryos.
In August 2001, President Bush, citing ethical questions, announced that federal funding for embryonic stem-cell research is limited to existing stem-cell lines.
The UW researchers isolated liver stem cells from aborted fetuses that were donated to research.
The university's team also manipulated the stem cells with special laboratory cultures to become cells of the bile duct, cartilage, fat, bone and blood vessels.
"We found a bunch of cells with this tremendous capacity to differentiate," Fausto said.
Dr. Eric Lagasse, a University of Pittsburgh expert on liver stem cells, told The Times that the UW research was important because the scientists were able to both isolate the liver stem cells and grow them into basic liver and bile-duct cells.
The UW team used chemicals to separate the stem cells from 2-.to 4-month-old fetal livers, which are more likely to have the so-called progenitor cells than are adult livers.
"It was a delight when we saw these cells were capable of (partially) repopulating the damaged liver," Fausto said.
Fausto said the researchers "gained tremendous understanding of human embryology, cell origins and how the liver is put together" from the research.
