Rather than science news, Nature Reports focuses on the political (I believe this is available without subscription, but let me know if you need a copy and can’t access it):
Nature Reports Stem Cells
Published online: 17 October 2007
Scientific definition by political request
(by) Monya Baker
The NIH must set criteria for pluripotency in human cells
Within a month, the US National Institutes of Health (NIH) hopes to start adding to the registry that lists the human embryonic stem cell (ES cell) lines eligible for US federal research funding. The registry currently contains only the human ES cell lines already in existence in August 2001, when President George W. Bush declared that no federal funds could be used for subsequently created lines. But of the dozens of human ES cell lines established since then, none will be added to the registry (with the possible exception of a few created by an unconventional technique that removes individual cells from embryos without destroying them). Instead, the word ‘pluripotent’ will replace the word ’embryonic’ in the name of the NIH Human Embryonic Stem Cell Registry, and the list will begin to include cell lines derived from non-embryonic sources.
The impetus for the change comes from the White House in the form of a executive order that touts the potential of non-embryonic stem cells, and accompanied Bush’s veto of popular legislation to lift restrictions on federal funding for research on human ES cells1. Researchers who derive and assess potentially qualifying lines will be given higher priority for new NIH grants and will be eligible for supplemental funds for existing grants. Before that happens, however, the NIH Stem Cell Task Force must set criteria for pluripotency in human cells. Politics has, essentially, mandated that an answer be found to a fundamental scientific question.
Asked about registering lines already clearly eligible for federal funding, scientists interviewed for this article generally reacted with a mixture of confusion, annoyance and indifference. One called the plan a “distraction that won’t open any doors”, and then asked not to be identified discussing politics. Some worried that political pressure on the NIH would hamper its ability to set a compelling definition. “I look forward to the day when the [registry] website is simply shut down, as its mere existence is a constant reminder of a public policy that does not serve the public good,” says stem-cell pioneer James Thomson at the University of Wisconsin-Madison. Of the two dozen or so human ES cell lines eligible for US federal funding, his are the most widely used.
“The term pluripotent has been used for every type of stem cell,” says Anthony Atala at Wake Forest University Baptist Medical Center, who recently identified stem cells in amniotic fluid that can differentiate into cell types representing bone, endothelial, fat, liver, muscle, and neuronal lineages. Originally, ‘pluripotent’ meant a cell could give rise to cells representing the three germ layers found in early embryos. To assess this property, scientists can inject mouse or human cells under the skin of an immune-compromised mouse and see whether they form a benign tumour known as a teratoma. But as the field advanced, says Atala, more requirements were added to the term.
The registry will help scientists to coordinate their research and share cells and information. Including the cells that demonstrate embryo-like markers and growth patterns will fill in a gap that currently exists with the current embryonic stem cell registry at the NIH. And it seems to be desired by some researchers:
“Being on the registry seems to be important to a lot of people,” Landis says, even when no one doubts the cells are eligible for federal funding. For example, representatives of groups that store umbilical cord blood have made enquiries, although their materials do not qualify as cell lines. Landis declines to speculate on their motivation, but researchers naturally want to boost the prestige and commercial value of their cell lines, and getting listed on the NIH registry would be one way to do that.