In 1998, a group led by Prof. James Thomson, at the University of Wisconsin, isolated embryonic stem cells (ESCs) from humans for the first time. These pluripotent cells are specifically isolated from four- or five-day-old blastocysts (pre-implantation embryos containing approximately 150 cells).
To generate the hESCs, Thomson’s group used blastocysts from in vitro fertilization (IVF) clinics with full donor consent. Since then, additional hESC lines have been created, often using blastocysts from IVF clinics that would otherwise be discarded (due to being damaged). Since IVF has become such a popular practice (now responsible for 1 in 100 births in the U.S.), there are now over half a million frozen embryos in the U.S. alone; there does not appear to be a shortage.
In 2001, President George W. Bush adopted a rather restrictive hESC policy, limiting the number of hESC lines that researchers could use and still receive federal funding; work with only 21 of the originally created lines could be federally funded (and no newly generated lines would receive federal funding). (However, work with other hESC lines could still receive private funding.)
President Barak Obama’s administration changed Bush’s policies. Specifically, in March 2009, Obama made it possible for researchers to receive federal funding for research on at least 75 different hESC lines; lines could be funded as long as the embryos used had full consent of the donors and the embryos would have otherwise been discarded (after use in an IVF clinic). However, federal funding could still not be used to generate new hESC lines.
Obama’s new policy quickly brought about a lawsuit, led by Nightlight Christian Adoptions and two adult stem cell researchers, Dr. James L. Sherley (a former MIT researcher who notoriously went on a hunger strike after being denied tenure) and Dr. Theresa Deisher (president and founder of Sound Choice Pharmaceutical Institute). The plaintiffs claimed that the new policy violated the Dickey-Wicker Amendment (established in 1996), which states that federal money cannot be used for any “research in which a human embryo or embryos are destroyed, discarded or knowingly subjected to risk of injury or death.” The Obama administration’s policy had bypassed this Amendment because it did not allow for federal funding of the generation of hESCs, but only for their downstream use.
To determine how valid the objection against hESC research is based on its use of human embryos, it’s important to understand two key aspects of hESCs’ unique biology and derivation. First, unlike adult stem cells, hESCs can be grown and expanded indefinitely, creating potentially an infinite number of hESCs from a single human embryo. Consequently, most research facilities that use hESCs do not generate the cell lines themselves, but purchase them from a banking facility (such as WiCell) or a collaborator. Second, researchers have shown that it is possible to generate a hESC line without damaging the embryo (although, admittedly, this is not how the hESC lines are typically created) (see Klimanskaya et al., 2006). Not only is it possible to create hESC lines without destroying a human embryo, or create potentially infinite hESCs from a single human embryo, but most researchers who work with these lines never encounter the donated human embryos used. However, this has not stopped Dr. Sherley and Dr. Deisher from appealing their suit.
Last year, the suit was dismissed because the plaintiffs would not be materially affected by a possible change in the policy. However, the suit went to the Court of Appeals, which reversed the ruling because it claimed that Dr. Sherley and Dr. Deisher were harmed by Obama’s policy; as they only worked with adult stem cells, theoretically they would have to deal with increased federal funding competition. In these economically tight times, one wonders how many other researchers might resort to prosecuting away their competition for funding sources. Dr. Sherley and Dr. Deisher became the only plaintiffs remaining.
On August 23rd, 2010, Chief Judge Royce C. Lamberth (who was appointed in 1987 by President Ronald Reagan) ruled to block Obama’s new hESC policy, asserting that federal funding could not be used in hESC research because the research “necessarily depends upon the destruction of a human embryo.” Judge Lamberth continued to state that, “If one step or ‘piece of research’ of an E.S.C. research project results in the destruction of an embryo, the entire project is precluded from receiving federal funding.”
Judge Lamberth claimed that his ruling was simply a return to “status quo,” but many are unclear, and understandably quite concerned, about the implications of the ruling; does this mean there will be a return to Bush administration policies, or can no hESC research be federally funded at all? The ruling has shocked the National Institutes of Health (NIH) and researchers alike, disrupting research in hESC laboratories across the country. However, the NIH already declared that the ruling would not affect grants that have already been paid this year, but renewals and grants currently being reviewed will be postponed. It will take some time to clarify the impacts of the ruling, although the Obama administration quickly announced, on August 24th, that it would appeal Judge Lamberth’s decision. However, it is not easy or efficient to simply put hESC research on hold; these cells are delicate, and require time to get going once they have been stopped.
Luckily, many hESC laboratories have alternative, private funding that is not affected by this ruling. The most significant remaining funder of hESC research is probably the California Institute for Regenerative Medicine (CIRM), which in 2004 was given $3 billion (through Proposition 71) to spend on stem cell research by Californian voters. (Luckily, my laboratory in the University of California, Santa Barbara, is one of such stem cell facilities funded primarily by CIRM.)
For more coverage on Judge Lamberth’s ruling against Obama’s hESC policies, see The New York Times’ article on “U.S. Judge Rules Against Obama’s Stem Cell Policy,” The Los Angeles Times’ article on “Ruling a blow to stem cell research,” National Public Radio’s article on “Obama Appeals Stem Cell Ruling; Some Work to Stop,” or The Forum on Science, Ethics, and Policy’s article on “Court Ruling Prevents Funding of Embryonic Stem Cell Research.”
I would be interested to hear about hESC policies in other countries, especially in the European Union. From what I’ve heard, there seems to be great variation, even within the EU.