More on Embryonic Stem Cells (For the not-so-dummies)

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christian_new.jpgBecause of heightened interest in my last piece, Stem Cells for Dummies, I decided to pursue further questions pertaining to scientific interest in embryonic stem cells (ESCs).

Pluripotent stem cells: elixirs of life
Recall we said that ESCs possess the quality of pluripotency, that is, the ability to develop themselves from an undifferentiated cellular state into most any differentiated cell type in the human body.  This wide-ranging capacity for differentiation—this pluripotency—is the coveted property of ESCs.  Defenders of the research dream of a day when the powers of ES cell pluripotency have been fully harnessed.  They reason: since degenerative diseases (such as Parkinson’s, Leukemia, Alzheimer’s, cardiac, liver and kidney disease, Lou Gering’s Disease … you name it) are caused by various kinds of tissue failure; if we can just control the regeneration of tissue by controlling the differentiation mechanisms of ESCs, we can definitively conquer degenerative disease!  The lame shall walk, the blind shall see, and all sick persons know the good news.  But we need embryos, lots of embryos.

Problem: tissue rejection
Tissue rejection, however, is one major obstacle.  The body’s immune system is designed to attack foreign substances in the body, including foreign tissues such as stem cells.  Stem cells harvested from an embryo possess the unique biological properties of the embryo, not the patient into whom they are transferred.  Thus people receiving treatments with stem cells risk suffering an immunological rejection of the foreign cells.

Solution: patient specific stem cells through human cloning
The concept of cloning is rather simple; and Dolly the Sheep gave proof in principle that it could work in mammals.  The nucleus of most every cell in my body contains a copy of my complete genetic code.  Obviously not all of the code is active (‘turned-on’) in every cell—e.g., in a skin cell, only the section coding for the production of skin tissue is active—but the complete code is present.  So if I remove the nucleus of (say) a skin cell, I now have a tiny bio-module containing my complete genetic blue-print (down to my sky blue eyes and luxuriant eyelashes).  I now secure a oocyte (egg cell) from a female donor using dangerous hyper-ovulation drugs [1], and remove and discard the egg’s nucleus; then I transfer the skin cell nucleus (my bio-module) into the enucleated egg.  By discarding the egg’s genetic material (which, remember, is only half of what’s necessary for the conception of an embryo) and replacing it with my complete genetic code, I essentially produce an embryo with my genetic blue print (after all, an embryo’s body is constituted of an egg and a complete human genetic code, half from mom and half from dad).  The embryo is a genetically identical copy of myself—a clone.  I now grow the embryo to day five and destroy it for its stem cells.  Because the embryo is genetically my twin, the stem cells genetically are my stem cells.  Hence, they can be used to treat my diseases without concern for tissue rejection.

As yet no one has successfully isolated patient specific ESCs from cloned embryos.  So no one knows whether the benefits they promise will ever be realized.  Cloning is biologically so unnatural that immense obstacles need to be overcome before clinically useful cells from clones can be derived. (Of course, it’s also grossly immoral, but I defer a detailed discussion of this to another piece.)
   
Induced Pluripotent stem cells: iPSCs
What if we could produce patient specific pluripotent stem cells from sources other than human embryos?  And what if the sources were virtually unlimited, the cost relatively low, the yield of useful cells high, and the procedure relatively simple?  It would mark an astonishing scientific accomplishment worthy of support by opponents and defenders of embryo destructive experimentation.  This is precisely the breakthrough that was made in November 2007.  Scientists at the University of Kyoto in Japan, and the University of Wisconsin, Madison, simultaneously published papers showing that it was possible to reprogram differentiated cells (such as skin cells) back to a state of pluripotency functionally identical to the pluripotency of ESCs.  In other words, the teams were able to reverse the differentiation process of a mature cell—i.e., to de-differentiate highly specialized cells back to the undifferentiated state of pluripotency.  They called them induced pluripotent stem cells (iPSCs).

Can you see the significance?  If someone is suffering, say, from brain injury; we take some of his skin cells, of which he has hundreds of millions; and we induce them to de-differentiate back to a state of pluripotency; then we prompt them again to differentiate, but this time into cerebral tissue.  Since the original cells were his own, with his own genetic code, the cerebral tissue that develops will be, genetically speaking, his brain tissue.  And there will have been no need for human embryos or dangerous hyper-ovulation drugs for egg-donors.  As more and more stem cell scientists are turning attention to iPSCs, it is becoming increasingly clear that irrespective of the ethical advantages—which are enormous—iPSCs offer distinct scientific advantages over stem cells produced by clone-and-kill procedures.  So both good science and good ethics witness to the value of this type of research.

Bright future? Regressive policies of the Obama administration

Not many know this, but when President Obama reversed the Bush stem cell policy on March 9, 2009, thus opening federal funds for the first time to research involving the destruction of human embryos, he simultaneously revoked a Bush Executive Order from 2007 explicitly encouraging the NIH to explore and fund sources of pluripotent stem cells that do not involve destroying human embryos.  The most promising of these is, of course, the new research with iPSCs.  In fact, the groundbreaking research published by the team at the University of Wisconsin in November 2007 was partially funded by an NIH grant made possible by the Bush Executive Order. 

Moreover, in his public comments at the signing ceremony Obama led people to believe his administration was firmly opposed human cloning, when it seems clear he actually supports clone-and-kill research.  He said: “We will ensure that our government never opens the door to the use of cloning for human reproduction.  It is dangerous, profoundly wrong and has no place in our society, or any society” [2].  But ‘cloning for reproduction’ is code language for cloning with the intention of implanting cloned embryos in a female uterus to bring to birth a live baby.  It does not include, nor does Obama’s Executive Order in principle restrict, cloning human embryos with the intention of growing them to day five and killing them for their stem cells.  So by freeing funds for embryo destructive experimentation, his Executive Order is in fact the first step in securing federal money for human cloning.  If Congress passes an ESC research bill in its next session, which it seems set on doing, it is likely to include a provision permitting federal funding for clone-and-kill research.  A memo on March 31, 2009, by the National Right to Life Committee to members of the U.S. House of Representatives stated:

A legislative ‘bait and switch’ is in the works.  We anticipate that the forthcoming ‘embryonic stem cell research’ legislation (1) will give NIH authority broad enough to fund research that uses not only ‘leftover’ human embryos but also created-for-research human embryos, including embryos created by human cloning; and (2) may be coupled with a clone-and-kill provision, which will be labeled as a ‘ban on human cloning’ but which will actually define ‘human cloning’ in a manner that allows the mass creation of human embryos by cloning, for the purpose of using them in research that will kill them.

 
During his historic campaign, President Obama promised to get politics out of science, while upholding the highest ethical standards.  Yet he has cancelled federal support for promising new research that science and ethics agree should be the future of pluripotent stem cell research; he’s made tax payer funds available for inferior and immoral old science whose track record in providing clinical solutions to human disease is appalling; and he has laid the foundation stone for the federally funding of clone-and-kill research.  Pretty poor batting average.

[1] See the campaign “Hands off our ovaries!” sponsored by Concerned Women for America: http://www.cwfa.org/articledisplay.asp?id=10452&department=CWA&categoryid=life

[2] See “Obama Says Government Will Not Open the Door for Human Cloning,” FOXNews.com, March 09, 2009, available at: http://www.foxnews.com/politics/first100days/2009/03/09/obama-says-government-open-door-human-cloning/

 

 

(c) Culture of Life Foundation 2009.  Reproduction granted with attribution required.

A legislative ‘bait and switch’ is in the works.  We anticipate that the forthcoming ‘embryonic stem cell research’ legislation (1) will give NIH authority broad enough to fund research that uses not only ‘leftover’ human embryos but also created-for-research human embryos, including embryos created by human cloning; and (2) may be coupled with a clone-and-kill provision, which will be labeled as a ‘ban on human cloning’ but which will actually define ‘human cloning’ in a manner that allows the mass creation of human embryos by cloning, for the purpose of using them in research that will kill them.

 
During his historic campaign, President Obama promised to get politics out of science, while upholding the highest ethical standards.  Yet he has cancelled federal support for promising new research that science and ethics agree should be the future of pluripotent stem cell research; he’s made tax payer funds available for inferior and immoral old science whose track record in providing clinical solutions to human disease is appalling; and he has laid the foundation stone for the federally funding of clone-and-kill research.  Pretty poor batting average.

[1] See the campaign “Hands off our ovaries!” sponsored by Concerned Women for America: http://www.cwfa.org/articledisplay.asp?id=10452&department=CWA&categoryid=life

[2] See “Obama Says Government Will Not Open the Door for Human Cloning,” FOXNews.com, March 09, 2009, available at: http://www.foxnews.com/politics/first100days/2009/03/09/obama-says-government-open-door-human-cloning/

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