an Stem Cell Process Found
Researchers develop way to derive stem cell lines using only human-based
January 3, 2006
Scientists have developed and successfully tested a new medium for
growing stem cells that does away with animal products that could harbor
contaminants, such as viruses.
The work by researchers at the WiCell Research Institute, a private
laboratory affiliated with the University of Wisconsin-Madison, is
reported in the journal Nature Biotechnology, published this week.
"This work helps us clear some of the major hurdles for using these
cells therapeutically," said the project's lead scientist, Tenneille
Ludwig, a UW-Madison researcher working at WiCell.
"All of the concerns about contaminating proteins in existing stem cell
lines can essentially be removed using this medium," he added.
The project helps push forward the field of stem cell research after its
most important work of 2005 was discredited. South Korean professor
Hwang Woo Suk retracted results that claimed to demonstrate stem cell
lines could be created from individual patients (see Korean Cloning Data
Until now, when biologists grew stem cells in a medium, they carefully
included a complicated mixture of hormones, growth factors, and blood
serum that came from animal cells.
While a few groups of scientists have cultured already-established human
embryonic stem cells in an animal-product-free medium, none managed to
derive new stem cell lines in this way.
"We describe the derivation of two new human embryonic stem cell lines
in... culture that includes protein components solely derived from
recombinant sources or purified from human material," reads the paper.
The two new cell lines managed to survive without developing
abnormalities for four and seven months.
"It is unclear how much these changes are related to the medium at this
point, as we have occasionally observed similar changes in previous
culture conditions," said James Thomson, professor of anatomy at
Seven years ago, Professor Thomson was the first person to successfully
grow human embryonic stem cells in the laboratory.
The scientists hope their findings will help reopen the debate over
federal funding of stem cell research in the United States.
At the moment, the human embryonic stem cell lines approved for this
funding source depend on products from mice.
"Derivation and culture in serum-free, animal-product-free,
feeder-independent conditions mean that new human embryonic stem cell
lines could be qualitatively different from the original lines, and
makes current public policy in the United States increasingly unsound,"
reads the paper.