Mo’ Stem Cells, Mo’ Problems
Like nanotechnology, particle physics, and alchemy before it, stem cell research has become the latest media-attention buzzword scientists dream about. In recent years, as debate rages and hope builds over these cellular shape-shifters, cell biologists have received increasing celebrity value from their peers and the general population. Stem cell researchers publish their papers in top-tier journals, get written up by The New York Times, and snag interviews on CNN. Last month, another cell biologist got his 15 minutes, and kicked up a political storm, when he isolated multipotent stem cells from amniotic fluid, the liquid in which babies float.
In a study that took a total of seven years, Anthony Atala’s group at Wake Forest devised a way to isolate aminiotic fluid-derived stem cells (AFS), using immunoselection. These cells expressed stem cell markers and did not show signs of differentiation, similar to the type of stem cells previously isolated from embryonic tissue. As described in both the original paper and the news articles it inspired, the cells were derived from both mouse and human amniotic fluid samples, and both species’ cells could be differentiated into neural, hepatic, and bone cells in mouse models and in culture.
The ability of these cells to be differentiated allows them to be labeled as pluri- or multipotent, but not the more valuable totipotent status awarded stem cells derived from embryos. The potency of “stem” cells reflects their ability to be used to form various body tissues, and by extension, their potential utility as a clinical treatment. At conception, a totipotent cell is made that will replicate into other totipotent cells, the true stem cells that can mature into every cell in the body. After a few rounds of replication, totipotent cells mature into pluripotent cells that have the ability to become many different, but not all, cell types. After pluripotent cells replicate, they give rise to multipotent cells, which give rise to different cell types, but are mature. The amniotic stem cells isolated in this article are likely to be either multipotent or pluripotent, similar to stem cells that have been isolated from adult bone marrow.
This difference, while subtle and perhaps esoteric to a general audience, is not ignored by major news publications. In the Associated Press article about the discovery, Atala and other scientists are given space to preach the importance of the AFS cells, but also warn that they are not a perfect substitute for the more controversial embryonic stem cells. Nevertheless, Atala’s finding is truly a critical advance in the understanding of human development and could prove to have therapeutic benefits down the road. It is thought that freezing down the AFS cells after a baby is born would create a stock of cells to allow for tissue replacement later in life. While this potential use is both wildly speculative and likely decades away from widespread implementation, it does raise some hope for early childhood diseases that are not genetic based.
However, like so many claims made by scientists about stem cells as well as other laboratory breakthroughs, the therapeutic advances are not as definitive or as guaranteed as stated. Many diseases that would potentially be treated with stem-cell-derived tissue regeneration are genetically-based diseases. For instance, childhood leukemia may someday be treated with bone marrow transplants derived from AFS cells, but it is currently unclear whether the bone marrow made from the AFS cells would still contain the genetic mutation that caused the cancer in the first place. Before AFS cells become a reliable resource for human transplantations and the treatment, the genetic basis of such diseases must be better understood.
One of the most interesting ramifications of this study arose not from the scientific advance itself or the traditional media’s news coverage, but rather from the hysterical reaction the finding inspired on both sides of the political fence. Right-wing blogs such as Instapundit and Townhall.com have declared Atala’s finding as a win for the pro-life camp, claiming that pro-stem cell politicians overstated the need for embryonic stem cells. More presumptuously, conservative bloggers also held up the study as proof that if scientists are pushed hard enough, they can overcome technical obstacles without having to tread upon ethically dangerous territory. Of course, most of these spinsters don’t bother to mention, or don’t realize, the critically important differences between AFS cells and embryonic stem cells.
Even those bloggers who do acknowledge the difference between ES and AFS cells attempt to twist the facts into a claim that AFS cells may be “better” than ES cells. The blog Answers in a Genesis wrote “This new research indicates that [AFS cells] have lost little, if any, ability to potentially differentiate into many, if not all, types of tissues. This degree of maturity may account for another apparent advantage of AFS. These cells do not appear to present the risk of developing tumors.” While these statements have yet to be proven entirely false, and are suggested by preliminary findings in the Atala paper, they haven’t yet been proven to be true either. Politicians have also tried to play the opposite-game, such as Rep. Joe Pitts’ claim that “these cells are showing more promise than embryonic stem cells,” a claim that is patently untrue. At this point, the research on AFS cells as a potential alternative to ES cells is limited to one solitary paper, so any such wild speculation remains premature and naive.
While right-wing blogs pounced on this issue more than left-wing commentators, at least one war of words did develop between two prominent political voices: The National Review, a prominent Conservative newsmagazine and website, and the Center for American Progress, a liberal think-tank. After the White House released the domestic policy statement “Advancing Stem Cell Research Without the Destruction of Human Life,” which prominently cites the Atala study as support for the ban on federal funding for most embryonic stem cell research, Jonathan Moreno and Sam Berger of the Center for American Progress wrote a critique in which they chastised the White House for embellishing the importance of the AFS cells and their ability to replace ES cells. They point out that the White House report championed the work of scientists who have come up with alternate methods of acquiring stem cells, while neglecting comments made by these very same scientists declaring their own discoveries to be unacceptable substitutes for stem cell research.
Yet in true partisan fashion, Moreno and Berger themselves also exaggerated the need for ES cells while downplaying the utility of AFS, merely reversing the White House’s own bias. Ramesh Ponnuru, National Review Senior Editor, then came to the defense of the White House and bashed the Moreno and Berger article and the Center for American Progress. Even though Atala himself came out and maintained that his paper does not suggest that AFS cells are suitable replacements for ES cells, as the White House report claimed, Ponnuru countered “Does Atala's letter change anything? Not that I can see. Atala basically offers his conclusion about what federal policy should be: that it should fund all types of stem cell research. But again, if you are willing to concede anything to the opponents of embryo-destructive research, his work strengthens [the anti-embryo research] case. He is entitled to his political views, of course, but he can't control the implications of his work.” Ponnuru ignores the prevailing scientific opinion that AFS cells are not able to replace ES cells. Moreno and Berger countered with “Ponnuru provides an entertaining rant, replete with rhetorical flourishes and pithy phrases worthy of a first rate polemicist. But when science is the issue, it’s often best to let the scientists speak for themselves.” In the end, neither side seemed to really care about getting the science behind the story correct, instead becoming mired in the usual partisan tunnel vision and petty name-calling.
Nevertheless the profile of AFS cells was raised by this groundswell of Internet discussion, and the argument may foreshadow events that will transpire in the halls of Congress. Of course, this advance could not have come at a more interesting moment of political climate change. The Democrats have taken over control of Congress, and, as part of their “First 100 Hours” initiative, immediately began pushing for federal funding of embryonic stem cell research, a move that provoked the White House’s latest stem cell policy statement. Meanwhile, social conservatives are reeling from Bush’s low approval ratings and pro-life politicians that are opposed to the destruction of embryos have increased their political ammunition and rhetoric. With a stem cell bill passing through the House, the White House reiterated their hard-line stance condemning the destruction of embryos, implying that any Congress-approved legislation would meet the same quick veto by which a 2006 bill was summarily euthanized. With both sides digging in their heels, the media’s fascination with the battle for federally funded stem cells research appears to be strong as ever, and from the reaction of the blogosphere, Atala’s finding has added even more kindling to the debate’s already considerable fire.
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SIN (Science in the News)
Too often, the media’s reporting on scientific findings and issues becomes a professional game of Telephone, with each re-telling adding an extra layer of misunderstanding, miscommunication, erroneous information, and dumbed down simplification. Each week, we will take a recent news story and attempt to excavate the original truth behind the hype, correcting the errors of the media’s coverage, commenting upon reoccurring issues with the science-to-public pipeline, and analyzing the motives and machinery behind these distortions.