Yesterday, extending a public debate that I participated in earlier in the week, I criticized some arguments by Reason's Ron Bailey and started to criticize some writings by the Discovery Institute's Wesley Smith. I'm pretty much done with Bailey (see our exchange here), with whom I really don't disagree all that much. But I have more to say about Smith's arguments on the stem cell issue.
In my previous post, I left off by objecting to Smith's attempt to create what I view as a false opposition between adult and embryonic stem cell research. There's much more to say here. In particular, I'd like to highlight some important points that the adult stem cell promoters never really seem to acknowledge, but which seriously weaken their arguments. (For a much more detailed discussion, please check out Chapter 12 of The Republican War on Science.)
First off, we already know that from a research standpoint, there are some things that adult stem cells will never achieve. For instance, they'll never be able to teach us about the processes of early embryonic development and cellular differentiation--processes that take place before more specialized adult stem cells have even come into existence. For this, you obviously need to study embryonic stem cells.
We also know that human adult stem cells have been studied for many years, and most of the advances in this area come from bone marrow stem cells. Much of the research here was done by Stanford's Irving Weissman, nowadays a leading supporter of embryonic stem cell research (a fact that really goes to show you that scientists don't think of the two fields as being in opposition). Weissman discovered blood-forming bone marrow stem cells many years before the discovery of human embryonic stem cells by Jamie Thomson at Wisconsin. Those cells haven't been studied nearly as long, and their study has been impaired by politics.
Finally, we know that adult stem cells are harder to isolate in the body, available in smaller amounts, and more difficult to grow. In short, these cells have drawbacks too. It's unfair not to point that out when discussing this issue, but the adult stem cell promoters never seem to do so.
But enough with the adult stem cell issue. Smith also uses other questionable science-based arguments to denigrate embryonic stem cell research, such as the constantly repeated Alzheimer's attack:
If stem cells have little 'practical potential to treat Alzheimer's,' why do proponents of cloned-embryo research continue to invoke a cure for Alzheimer's in their sales pitches?
In my view, those who attack embryonic stem cell work over the Alzheimer's issue are using a very selective description of what this research is really all about. Embryonic stem cell research isn't merely being conducted so that we can learn how to grow specialized tissues that can then be used to cure diseases through transplantation. It involves much more than that.
Because it is a complex brain disease, Alzheimer's probably won't be treated through stem cell transplantation. Smith is right about this. But new insights into the nature of the disease could nevertheless be gained through embryonic stem cell research or the related therapeutic cloning research. If we had embryonic stem cell lines with the genetic signature of Alzheimer's--lines that would probably have to be developed via somatic cell nuclear transfer of genetic material from an Alzheimer's patient's cells into an enucleated egg--we could not only study how the disease develops, but potentially test new Alzheimer's drugs on these cells.
So it's not wrong to talk about Alzheimer's in the context of embryonic stem cell research, as long as you know what it is that you're talking about. To be fair, perhaps some advocates for the research have been incautious about this. But those who use the Alzheimer's issue to attack embryonic stem cell research are equally incautious, probably more so.
Finally, Smith has also raised questionable safety concerns about embryonic stem cell research. For example, in the course of praising umbilical cord stem cells he wrote the following:
Unlike embryonic stem cells, UCB stem cells don't cause dangerous tumors. Moreover, they are easier to tissue-type to prevent rejection than are bone marrow stem cells. And here's another big plus: This research is utterly uncontroversial. No embryos are being cloned. No embryos are being destroyed.
The claim that embryonic stem cells will cause tumors, or teratomas, has some technical truth to it but really amounts to a scare tactic. I recently had the opportunity to discuss this topic with Robert Goldstein, chief scientific officer of the Juvenile Diabetes Research Foundation. He explained to me that while embryonic stem cells have the potential to form teratomas (due to robust growth and differentiation into different cell types), well characterized lines can be observed to make sure that they are mature and no longer behave in this way. And of course, no one is going to inject someone with cells from a line unless that line is known not to produce teratomas. To do otherwise would be completely unethical. So this is not a practical problem.
So, when it comes to Wesley Smith's recent writings in the one area where we really overlap--embryonic stem cell science--I'm fairly troubled by them. In my view, it's fine to oppose research on ethical grounds, in the sense that ethical positions are debatable and everyone's entitled to his or her own perspective. But scientific information shouldn't be molded to make one particular ethical perspective seem stronger than it otherwise might.
To be fair, Smith's arguments on these topics--the promotion of adult stem cells, the Alzheimer's attack, the tumors argument--are broadly consistent with the arguments of many other anti-research conservatives. It's not like he's the only person doing this.
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Chris, by all means Smith is entitled to his opinion. But I wonder:
Is it ethical for him or his immediate family to accept any medical protocol that could conceivably have been developed from research he says he's morally opposed to?
Let's say research into embryonic stem cells produces a viable treatment for some other kind of brain dysfunction than Alzheimer's, say Parkinsonian tremors. Does Smith have the right to avail himself of that treatment if he comes down with Parkinson's?
IMHO, no. But I don't think a medical professional has the right to refuse that treatment option, either.
Hi Chris-
You are correct that stem cells CAN be connected to Alzheimer's through a convoluted stream of hypotheticals, but there is no doubt that scientists abuse this link to manipulate the public. Why would they do such a thing? Quite simply, scientists are human beings with distinct self-interests and political motivations. When science is your livelihood and your research is government funded, survival requires "selling" your research to an undereducated public. Scientists sell cures because cures sell science.
In my opinion, declaring these assertions over-hyped and irresponsible does not amount to "using a very selective description of what this research is really all about." For the forseeable future, this research is ENTIRELY about learning "how to grow specialized tissues that can then be used to cure diseases." This is indeed a PREREQUISITE for the Alzheimer's research you describe. Alzheimer's is a neurodegenerative disease. We need to understand what triggers formation of amyloid plaques and neurofibrillary tangles, and how they exert toxicity on neurons. The use of SCNT to create "embryonic stem cell lines with the genetic signature of Alzheimer's" is just the beginning. These cell lines must be coaxed to develop into neurons (a specialized tissue indeed) before they can be studied as a model for Alzheimer's. They can then complement current Alzheimer's studies using neuronal cell lines not derived from stem cells (PC12 cells, for instance). Do you know how many technical hurdles must be cleared before these cells can exist? It certainly boggles my neurons.
"For the forseeable future, this research is ENTIRELY about learning 'how to grow specialized tissues that can then be used to cure diseases.'" No, I disagree. Much of this is just basic research to determine how embryonic stem cells actually behave, and what light that sheds on processes of development. And there's also likely to be a lot of research testing drugs in stem cell preparations. It's NOT just about transplantation.
I agree generally there are a lot of hypotheticals here, but scientists are really thinking seriously about doing this stuff. Finally, are the scientists the ones hyping Alzheimer's cures, or the advocates? I suspect it's the latter, not the former.
Chris: For a guy who claims to only be interested in the scientific facts, this column post is filled with everything but. I base my statements about adult stem cells on published science, not assertions or speculation. You cannot say the same. Indeed, have you even read the peer reviewed papers in these regards?
For example, you claim that my assertions about tumors and ES cells is "questionable." Yet, the literature shows that ES cells do cause tumors in animal studies. For example, in one reported study of ES cell treatments on mice with Parkinson's, the mice were given 1% of the usual dose and still 20% died of brain tumors. Tumors (in addition to tissue rejection) str a big issue and provide just one reason why it is unlikely that the FDA will approve ES cell human studies in the near future.
Then, of course, there is the problem that scientists cannot yet morph these cells into any tissue they want. We don't even know they will ever be able to do so. Any other assertion, such as the oft-heard claim that ES cells "can become any tissue in the body," is speculation, or perhaps better stated, hypothosis. This isn't the same thing as having been scientifically verified, and you of all people, should hold yourself to that standard in your advocacy, clearly labeling speculation, hypothesis, and hope apart from verified science.
Nor is bone marrow necessarily the primary source of adult stem cell therapies. For example, juvenile diabetes has been cured in mice with spleen stem cells. The FDA has approved the experiment for human tests. Nothing close to that on the embryonic side. Blood and fat stem cells have been shown to help heal heart tissue in human and animal studies. Umbilical cord blood stem cells have helped restore some movement and sensation to a paralyzed woman, as published in a peer reviewed journal. Mice with severed spinal coreds have been materially improved with olfactory stem cells. Annecdotally, this has also worked in humans. There is, I am told, going to be a peer reviewed report about this work published this year.
Great meeting you the other night, by the way. It was an interesting event.
Good post by Chris.
It's right and fine and helps prevent unrealistic expectations to point out the many technical problems to be solved in order to use cloned stem cells in Alzheimer's research, a truth often twisted, however, into a circular argument to NEVER ALLOW THE WORK TO BEGIN. "It's difficult, so don't try it." Imagine politicians had had the means to hold back the Wright brothers with that sort of attitude. Throw in a pile of legislative threats and roadblocks, then complain science doesn't lift off. Them eggheads can't win, can they?
It cannot be about the money either, since public funds for embryonic stem cells in Western countries are fairly miniscule in comparison to expenses on other related research topics, including multipotent cells.
Anarcho-capitalists oppose public funding of basic research on principle. I don't agree, but it's a coherent position. For the Religious Right, however, the funding disputes are little more than a useful distraction from their own dogmatic extremism. For someone who seriously equates the life of a person with that of an embryo, still allowing the research to proceed with private funds is almost inevitably a tactical gambit on the way to total prohibition.
As to the "adult vs. embryonic" PR battle, anybody with even marginal knowledge of cell biology can see it's a false dichotomy. The more genetic and epigenetic diversity of cell lines the research community has ready to hand for comparative study, the faster new tissue-engineering methods and molecular developmental mechanisms will be discovered.
The non-linear nature of biological inquiry thrives on open-mindedness, not ideological barriers. Conservatives decrying the catastrophic failures of socialist planned economy while trying to plan ahead and micro-manage the course of scientific discovery appear to be decisively more confused than ethical.
Thanks for writing in, Wesley. As to your points:
1. Tumors. No one is denying that embyronic stem cells can form teratomas. But obviously no one is going to inject a person with an ESC line if it's known to do this. And as I explained, we can watch and develop the lines to ensure that they no longer have this tumor-forming behavior. So why try to scare people about tumors?
2. When did I say embryonic stem cells have been proven to be able to form every different cell type in the body? I didn't say it here, and in fact, I was very careful not to make this claim in my book.
3. You provide yet another list of advances using adult stem cells. So what? I'm not saying there's anything wrong with this research, or denying that it exists. What I'm objecting to is the attempt to use findings in the adult stem cell area to denigrate or undermine embryonic research. I'm saying that the two fields of research are complimentary, not in opposition to one another. Therefore, it's a bogus argument to cite adult stem cell advances in order to attack embryonic research, or suggest it's unnecessary.
It was a pleasure to meet you as well on Tuesday. Thanks for engaging.
"Then, of course, there is the problem that scientists cannot yet morph these cells into any tissue they want. We don't even know they will ever be able to do so. Any other assertion, such as the oft-heard claim that ES cells "can become any tissue in the body," is speculation, or perhaps better stated, hypothosis."
This seems to cut at the heart of the matter. Not knowing how ESCs work or which tissues they can give rise to is not a valid argument against doing research on them, particularly when these happen to be the very things that the research is supposed to figure out! The goal of ESC research is to better understand the process of development, which is a necessary precursor to treating development-related diseases. To state that we don't know how they develop is simply to say that we need more research.
If people such as Jay Wesley Smith had their way and such research were banned, we'd remain ignorant of how exactly ESCs differentiate. This will, at the very least, delay solving one of the biggest issues of developmental biology. It could possibly delay it forever. Perhaps Smith thinks this is a worthwhile trade-off for whatever ethical gains he thinks will be made by stopping the research. If so, it would be nice for him to state and defend that argument up-front rather than make the bizarre claim that because we don't know about something, that's a good reason not to conduct research on it.
The previous post is an excellent rebuttal against the question of differentiation potential and general ESC utility raised by many ESC opponents. I would also like to add that researchers have had many decades to learn about and experiment with adult SCs, compared to a measly 7 years to explore ESCs (first report of successful isolation/culture by J. Thomson on 11/6/98). Thus, I find arguments comparing the clinical success of adult SCs vs. the lack of ESC therapies to be extremely frustrating. Seven years is a very, very short period of time when you're talking about making major discoveries related to complex biological processes. It took much longer than seven years for scientists to learn how to purposefully differentiate adult stem cells in a lab (our in vitro differentiation of adult SCs into several types of cells is often still quite crude and requires the use of many non-biological substances, further illustrating that our understanding of adult SCs is not as advanced as many would have the public believe). To refute any conflict of interest here, I also want to note that my own lab performs adult SC, but not ESC research.
I would also like to comment on one of Chris' posts above and affirm that he is correct in assuming that it is most often not the scientists themselves who are found publicly 'hyping cures'. Many scientists (including myself) have been absolutely appalled upon reading claims made in mainstream news stories about their work. We in the scientific community know that this sort of hype will eventually work against us, as the general public is impatient for cures and will rally against us when we do not produce as quickly as they expected. Anyone who reads reputable science journals will quickly learn that scientists actually suffer from the opposite problem - we are loathe to make definitive, concrete claims about *anything*; we use downright wishy-washy language such as 'these results *may* indicate that...' or 'these data *may suggest* a relationship between'. Use of more aggressive wording is actually sometimes a hallmark of a less-reputable publication.
Sorry Chris, but you are mistaken that nobody wants ES cells used in human research. Ian Wilmut, the creator of Dolly, is already urging that ES cells be injected in dying ALS patients despite knowing they are insufficiently tested to begin even State 1 human trials. He is asking the UK authorities for permission. See my article about that in the dreaded Daily Standard.
I didn't say you claimed that ES cells can make every cell in the body. I said that claim is continually made. I assume you are as indignant about this abuse of science as you are those perceived to come from the conservative side.
The adult stem cell issue is important because they should be weighted in the ethical balance about how and whether to proceed with therapeutic cloning research.
Cheers in 2006.
Thanks to everyone for commenting. I'll just close this thread with a few final comments to Anonymous.
First, if Wilmut wants to inject ESCs then I hope the lines are up for that. I'm a bit skeptical that they are. In any case, I strongly doubt he would be injecting people with lines known to form tumors.
The claim that embryonic stem cells can form every cell type of the body has not been proven yet, but it's gotten around largely through media repetition. I don't think there's any malice to it, though it ought to be corrected. The scientific reviewer of my own book chapter on this certainly corrected me on this point; I had been making the same error as everyone else up until that point.
However, this little error isn't comparable to the adult stem cell campaign, where it seems to me that there is a concerted effort to create a false opposition between two promising threads of research.
Finally: "The adult stem cell issue is important because they should be weighted in the ethical balance about how and whether to proceed with therapeutic cloning research." It seems to me that this statement presumes an that we may have to decide *between* these two strands of research. I reject that very notion. If these different strands of research are aimed at achieving things and have different potential, then why should we be choosing one or the other?