Posted on 11/28/2007 9:42:22 PM PST by Coleus
Now, I know what you're thinking: So suddenly scientists discover they can indeed reprogram adult skin cells back to a pluripotent state, the pro-life community goes wild with joy, the end of the stem-cell wars seems to be in sight, and Lydia gets cold feet about biting the bullet she said she would bite on exactly this sort of reprograming. (Mixed metaphor alert.) Those of you who slogged through my earlier ANT-OAR post will remember that I said that making pluripotent stem cells like embryonic stem cells in the lab is wrong even if it doesn't involve making and destroying any live embryos, because it is analogous to making a "headless body," which is macabre and prima facie unethical. At that time I admitted that a counterintuitive consequence of this position is that it would be similarly unethical to make such cells by reprograming adult cells back to a pluripotent state, but that I was prepared for the nonce to bite that bullet.So why am I rethinking?
Well, the cause of my second thoughts is only incidentally related to the recent explosive news of success in reprograming adult cells. In the course of reading about that research, I found out an empirical fact I never knew before: It seems that a small number of pluripotent cells are found free "in nature" in umbilical cord blood and in bone marrow. These cells are known as VSELs (very small embryonic-like cells). See also several abstracts here. They have not been fully tested for pluripotency, and scientists seem unsure as to whether they will pass the teratoma-formation test for full pluripotency (see here), but all the signs so far are that they are indeed exactly like the cells of the inner cell mass of a blastocyst. What I'm still a bit mystified about is why that discovery didn't end the stem cell wars already, even before the reprograming breakthrough. Why bother reprograming to pluripotency if we all have a few pluripotent cells floating around in our bone marrow already? Just isolate them and culture the heck out of them, and there you go. My only conjecture in response to that so far is that VSELs are apparently very rare, so maybe it just isn't possible to get enough of them, even with culturing.
But if indeed cells just like those of the inner cell mass exist in the human body naturally, this seems to me to call seriously in question the thesis that such cells are like "the dead bodies of embryos" or that inducing them in the lab would be like making a faceless Frankenstein monster. Prima facie, cells that are a normal part of the adult body are not analogous to such an unnatural entity and are not unethical to make. While normally I hate to have to change my mind publically as much as anyone else, in this case (as you can imagine), I'm not too sorry. After all, that means that I, too, can be pleased about the reprograming breakthrough along with the rest of the pro-lifers in the country.
As to what this means about ANT-OAR, I'm not sure. One of the reasons I'm not sure is that, as I noted in the comments thread to my earlier post, ANT-OAR has not been well-tested in animal studies yet, and there is a real ambiguity in its proponents' writings on how techniques involving gene knock-out differ from techniques involving the introduction of positive factors. This leaves open the possibility that a damaged embryo is created in ANT-OAR, a possibility that can't be ruled out until more testing is done. That point may be practically moot, however, as it seems to me that in view of the reprograming success, ANT-OAR--with its cloning-like aspects and its need for human eggs--is unnecessary. But in the main earlier post, I was granting for the sake of the argument that ANT-OAR could indeed create ICM cells without making a live embryo, and I was arguing that this would still be wrong. If it is actually true that a small number of cells like ICM cells are a normal part of the adult body, it seems to me that that conclusion must be incorrect. HT Life Ethics
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