posted by Damozel | Meanwhile, while some of us are fretting over the politicization of health care, scientists who have actually succeeded in deriving stem cells by "creating embryonic stem cells without having to destroy human embryos" have run up against a potential policy hurdle: performing research without doing more than minimal harm to the derived embryos (Washington Post). In a June 2007 Executive Order, President Bush required the Secretary of Health and Human Services to:
...conduct and support research on the isolation, derivation, production, and testing of stem cells that are capable of producing all or almost all of the cell types of the developing body and may result in improved understanding of or treatments for diseases and other adverse health conditions, but are derived without creating a human embryo for research purposes or destroying, discarding, or subjecting to harm a human embryo or fetus. (Order)
Done and done!
Unfortunately, the Bush Administration's current policy prevents the National Institute of Health from funding research on stem cell lines that didn't exist prior to August 9, 2001 or that might do minimal harm to embryos (Washington Post). I don't know about you, but I blame the scientists. Didn't they know back when they started that the embryos from which stem cells are derived are considered "living members of the human species"? (Order).
Now the scientists are complaining.
"This is not the way to make good health policy," said Robert Lanza, the frustrated vice president for research and scientific development at Advanced Cell Technology (ACT) in Worcester, Mass. Lanza submitted the study proposal with stem cell experts from several major research labs. (Washington Post).
Another time Dr. Lanza will read Administration and Congressional policies all the way through before he jumps in and expends time, money, and research on critical medical research.When the Bush Administration created its stem cell policy in 2001, it prohibited the NIH from conducting stem cell research on any stem cell lines that weren't in existence at that time (Washington Post). Bush said:
As a result of private research, more than 60 genetically diverse stem cell lines already exist. They were created from embryos that have already been destroyed, and they have the ability to regenerate themselves indefinitely, creating ongoing opportunities for research. I have concluded that we should allow federal funds to be used for research on these existing stem cell lines, where the life and death decision has already been made.
Leading scientists tell me research on these 60 lines has great promise that could lead to breakthrough therapies and cures. This allows us to explore the promise and potential of stem cell research without crossing a fundamental moral line, by providing taxpayer funding that would sanction or encourage further destruction of human embryos that have at least the potential for life. (August 9, 2001)
The problem: ""Currently, there are no cell lines derived from single blastomeres [the technique used by Dr. Lanza] listed on the stem cell registry as eligible for funding," Landis [of the NIH's stem cell task force] said." Well, there wouldn't be, would there, since Dr. Lanza only developed his stem cell lines after the date when the stem cell registry was implemented (?)
Dr. Lanza's outfit---Advanced Cell Technology---found a way to derive stem cells from an embryo without destroying the embryo. "A single cell, called a blastomere, is removed from an eight-cell human embryo, then coaxed [gently, I'm sure!] to multiply into a colony of stem cells in a dish" (Weiss). Apparently, fertility doctors have been performing "blastomere biopsies" of this sort for years, as a means of checking for genetically defective embryos. If the embryo is okay, it can be transferred to the mother's womb without concern that plucking out a cell for culturing will prevent it from developing. (Weiss). Dr. Lanza has created stem cells using this technique (which leaves the embryos intact). And Dr. Atala at Wake Forest (my alma mater!) announced in January that he has isolated stem cell equivalents from amniotic fluid (Washington Post).
In other words, they've derived new stem cell lines without engaging in the embryo-destroying processes banned by Congress and the Bush Administration. In case you don't know, an embryo is "is a multicellular diploid eukaryote in its earliest stage of prenatal development (links in original!)." Stem cells are derived from the inner cell mass of a clump of embryonic cells at the "blastocyst" phase, 4-5 days after the egg is first fertilized. Look at this picture of a blastocyst from Wikipedia; isn't it cute?
The stem cells in its inner mass are "pluripotent," meaning they can differentiate into any derivative of the primary germ layers (stem cells). From them, a scientist can cultivate each of the 220 types of cells found in adults. Or, as the NIH site puts it,
As long as the embryonic stem cells in culture are grown under certain conditions, they can remain undifferentiated (unspecialized). But if cells are allowed to clump together to form embryoid bodies, they begin to differentiate spontaneously. They can form muscle cells, nerve cells, and many other cell types. Although spontaneous differentiation is a good indication that a culture of embryonic stem cells is healthy, it is not an efficient way to produce cultures of specific cell types.
So, to generate cultures of specific types of differentiated cells—heart muscle cells, blood cells, or nerve cells, for example—scientists try to control the differentiation of embryonic stem cells. They change the chemical composition of the culture medium, alter the surface of the culture dish, or modify the cells by inserting specific genes. Through years of experimentation scientists have established some basic protocols or "recipes" for the directed differentiation of embryonic stem cells into some specific cell types (Figure 1). (For more examples of directed differentiation of embryonic stem cells, see Chapters 5–9 and Appendices B and C of the NIH report Stem Cells: Scientific Progress and Future Research Directions.)
If scientists can reliably direct the differentiation of embryonic stem cells into specific cell types, they may be able to use the resulting, differentiated cells to treat certain diseases at some point in the future. Diseases that might be treated by transplanting cells generated from human embryonic stem cells include Parkinson's disease, diabetes, traumatic spinal cord injury, Purkinje cell degeneration, Duchenne's muscular dystrophy, heart disease, and vision and hearing loss. (NIH)
Now Lanza, Atala, and "a team of others" have decided they needed to conduct a study to compare their stem cells to the ones harvested from destroyed embryos. (Weiss). Sadly, the NIH has had to halt the study for "administrative review." For one thing, the new cell lines aren't listed among those eligible for funding. For another, it's not clear whether the proposed research will cause harm to embryos.
For now, Lanza has suggested limiting his technique to embryos that are already due to be biopsied at a fertility clinic. The plucked cell could divide for a day, providing enough cells for both the genetic testing and to start a line of stem cells. That way the embryo would not be subjected to any new or additional risk.
Still, for funding, that risk would have to be "minimal" -- a standard open to "interpretative discretion," said R. Alta Charo, a professor of law and bioethics at the University of Wisconsin at Madison (Washington Post; link in original).
In an interview this week with The Washington Post, Bush said, ""there are ways to develop stem cell lines without the destruction of human life. There's a myriad of ways to advance good science without crossing an ethical line (Weiss)." The June 2007 Executive Order requires the HHS Secretary to "to rewrite the rules for funding stem cell research, with the emphasis not on whether the cells came from embryos but on whether any embryos were harmed" (Weiss).
In the June 2007 executive order, Bush defined "embryo" and "harm" as follows:
(a) For purposes of this order, the term "human embryo" shall mean anyorganism, not protected as a human subject under 45 CFR 46 as of the dateof this order, that is derived by fertilization, parthenogenesis, cloning, or any other means from one or more human gametes or human diploid cells.
(b) For purposes of this order, the term "subjecting to harm a human embryo" shall mean subjecting such an embryo to risk of injury or death greater than that allowed for research on fetuses in utero under 45CFR 46.204(b) and section498(b) ofthe Public Health Service Act (42U.S.C. 289g(b)) as of the date of this order.(Order)
So is the blastomere-plucking process [my phrase] pioneered by Dr. Lanza and described above eligible under the "no-what-don't-hurt-the embryo" test? Bush's 2005 Council on Bioethics had some doubts about the process. According to The Washington Post, the Council thought that stem cells so derived might be eligible but they weren't clear about whether the process harms the embryo. "[E]ven if development proceeds in a healthy manner, it may be that the child born is somehow a different child than the one that would have resulted from an undisturbed embryo" (Washington Post).
Is it possible that the soul with which the cell clump is infused from conception on somehow change if the embryo changes? Is tampering with an embryo---never mind whether it ever develops into an actual human---the same as tampering with a human soul? Does an embryo care if it's ever born or not? If it does, would it rather be born genetically defective rather than not be born at all? Does it mind having a cell removed at an early stage if there's a chance it might develop differently and turn into a different child? And if the answer is yes, does failing to let the embryo have its way constitute "harm" to the embryo or is it ethically permissible to say, "What do you know, kid; you aren't even wet behind the ears yet?"
And how many stem cells can dance on the head of a pin?
Landis, of the NIH, would not say how the agency will decide which cell lines involve risks small enough to be eligible for funding, nor would she say what role, if any, the White House will have in those decisions.
Agency insiders, however, said the NIH is likely to convene workshops and fund animal tests to study the degree of harm various procedures pose to embryos -- a meticulous approach that strengthens suspicions among research proponents that real stem cell policy changes are unlikely while Bush is in office.
"I think they're trying to ride the clock out," Lanza said. (Weiss).
Which---based on the recent revelations about the tribulations of former surgeon general Dr. Richard Carmona---may turn out to be the only way forward.
Stay tuned. If we're protecting clumps of undifferentiated cells, I'm sure we'll eventually work round to this. And by "we" I don't mean Catholics, either:
RELATED BN-POLITICS POSTS
- Bush-Appropriate Health News; or What's Good for the Bush Administration is Good for the World [Updated].
- Attacking Healthcare Experts: When will Bush's Spokespeople Learn?
Rick Weiss, Future of Stem Cell Tests May Hang on Defining Embryo Harm (Washington Post)
http://www.washingtonpost.com/wp-dyn/content/article/2007/07/28/AR2007072800993.html?nav=hcmodule
- Executive Order: Expanding Approved Stem Cell Lines in Ethically Responsible Ways
- NIH, Stem Cell Basics
- President Discusses Stem Cell Research (Crawford, TX August 9, 2001)
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