Heather Zieger looks at the stem cell debate from a biblical worldview perspective. This Christian perspective recognizes the true source of life and the difficulties with destroying many young lives for the hope of being able to save a few older lives.
What Are Stem Cells?
If science had a tabloid magazine, then stem cells would grace the cover. And much like the Hollywood celebrities, stem cells are at the center of controversy. How is a Christian to respond to conflicting reports and confusing science? In this article we will discuss the differences between adult and embryonic stem cells, look at some media myths, and evaluate the worldview issues behind the controversy.
First, let’s define stem cells. Stem cells are cells that serve as the body’s carpenters and mechanics to other cells. Their name comes from the stem of a plant. Think of a rose. From the stem grow the leaves, the thorns, and the flower. The flower does not produce leaves, nor do the thorns produce a flower, but the stem produces all of these things. However, the stem of the rose is still part of the plant. In the same way, stem cells are themselves cells and they produce other cells.
Stem cells can be found throughout our body. Think about when you give blood. Your body will resupply the blood that you lost. It does this by using blood stem cells. When your body needs more blood, signals tell the blood stem cells to make red blood cells, white blood cells and plasma cells. Another example is our skin. We lose skin every day, but our body has very active skin stem cells that grow new layers. Keep skin stem cells in mind, because scientists have been able to do some amazing things with skin stem cells.
Blood and skin stem cells are examples of adult stem cells, which are different from another type of stem cell called embryonic stem cells. Embryonic stem cells are only found in the inner cell mass of a 5- to 8-day-old embryo. These cells end up making every cell in the human body and can divide indefinitely. They are believed to be much more versatile than adult stem cells. Because of this ability, scientists describe embryonic stem cells as pluripotent. Adult stem cells are programmed to only make certain types of cells (like our example of blood stem cells), and adult stem cells have a limited number of cell divisions. Because of this, they are described as multipotent.
As we look at some of the scientific research on stem cells, we will find that adult stem cells are more versatile than we once thought, and embryonic stem cells have limitations that scientists still need to overcome.{1}
Adult Stem Cells: The Underreported Medical Successes
Oneof the two main types of stem cells is adult stem cells. Adult stem cells are named for their abilities, not for their source. We find very helpful adult stem cells in umbilical cord blood and the placenta even though these sources are not from adults. One of the most studied adult stem cell sources is bone marrow. The first bone marrow transplant was performed in 1968. But it wasn’t until 1988 that scientists identified the stem cells within bone marrow that caused the transplants to work.{2}
Bone marrow transplants demonstrate one of the biggest advantages of adult stem cells. Scientists did not know what a stem cell was, let alone how they worked, but the bone marrow transplants were still successful. The stem cells knew where to go in the body to repair the right tissues. This ability to automatically go to the location of repair is characteristic of all adult stem cells.
Bone marrow transplants also demonstrate one disadvantage to adult stem cell therapy. Just like an organ transplant, the stem cell donor must be an exact match to the patient. And the patient will need to take immuno-suppressant drugs for the rest of his life.
However, recent findings with umbilical cord blood have shown that the donor does not have to be an exact match when cord blood is used, meaning that a patient has a better chance of finding a donor. One of the first umbilical cord treatments was for sickle cell disease in a twelve-year-old boy.{3} He responded so well to treatment that a year later doctors declared him cured of sickle cell disease. He does have to take immune suppressant drugs, but does not display sickle cell symptoms.
One way around the donor problem is to use the patient’s own healthy stem cells to repair other damaged cells. Parents now have the choice to bank their child’s umbilical cord blood in the event that the child may need it. This technique was successfully used to help a child with her cerebral palsy symptoms.{4} Other adult stem cell successes include rebuilding bone, alleviating some cancers and auto-immune diseases, relieving Parkinson’s symptoms, and treatments for Type I diabetes.{5}
All of these therapies have happened in real people using stem cells that do not involve the destruction of an embryo, and would be perfectly ethical within a Christian worldview.
What is the Promise of Embryonic Stem Cells?
The second type of stem cell is embryonic stem cells. Embryonic stem cells come from the inner cell mass of a 5- to 8-day-old embryo. Embryos are formed after the egg and sperm have united, which initiates a directional process that, given proper conditions, can eventually form a baby. At the 5- to 8-day stage, there are only a few cells within the embryo, but these cells are capable of making all of the cells in the human body. To obtain these cells, scientists penetrate the outer protective layer of the embryo and remove the cells. This procedure destroys the embryo.
It is still only a theoretical possibility that human embryonic stem cells can cure diseases. There is one FDA approved human trial that was announced in January 2009 for patients with a recent spinal cord injury.{6} We will have to wait to find out the results of this treatment. In other parts of the world, people have sought embryonic stem cell therapy as a desperate measure. One man in China had embryonic stem cells injected into his brain to relieve his Parkinson’s symptoms. Unfortunately, the cells spun out of control and continued to make new cells of varying cell types. They eventually formed a large brain tumor consisting of different kinds of cells [a teratoma], such as skin cells, hair cells, and blood cells.{7} Another boy in Israel had a disease that attacked his spinal cord. His parents took him to Russia for several treatments with embryonic stem cells. Four years later, doctors found tumors in his spine that they confirmed came from the embryonic stem cell therapy.{8}
One of the most difficult hurdles for embryonic stem cell research is trying to program the stem cell to become the particular cell type that they need. The second hurdle is then telling the cell to stop multiplying before it forms a tumor. The signals and mechanisms for this are still being researched; however, one recent study involving the rebuilding of mouse muscles using embryonic stem cells shows some progress in this area.{9}
While embryonic stem cells may theoretically have promise, they have not shown this in reality. Time will tell if they actually deliver. However, the ethical issue from a Christian perspective is not whether this research has a practical use, but whether we want to go down the path of using the parts of one human being, deemed less worthy of life, for another.
Media Myths
Unfortunately, the stem cell debate has turned into a media poster child for the next big scientific miracle. And stem cells have been hot science topics in the political realm. What is striking in all of this are the misconceptions that are repeated in the media.
Let’s go over three media myths in the stem cell debate.
The first myth is that President Bush restricted stem cell research. Actually, President Bush was the first president to specifically allow federal funding for embryonic stem cell research.{10} However, he did put limits on how far they can take that funding. Furthermore, what is often omitted is that private companies have always been allowed to invest in embryonic stem cell research.
The second myth often repeated by the media is that embryonic stem cells have the potential to cure all types of diseases including spinal cord injuries,{11} Parkinson’s and Alzheimer’s. So far, the only successful stem cell treatments of spinal cord injuries or of Parkinson’s symptoms{12} have been with adult stem cells.
I want to emphasize that Alzheimer’s will never be cured by stem cell therapy of any kind. Alzheimer’s causes the death of many types of brain tissues. Stem cells might be able to replace some dead tissue, but tissue death is a symptom, not the cause. Alzheimer’s affects the whole brain so deeply and quickly that it really isn’t an issue of replacing cells. Therefore, scientists must look to other areas for cures for Alzheimer’s.{13} The perpetuation of the myth that stem cells will cure Alzheimer’s is either a cruel misrepresentation in order to sell a story, or else demonstrates a complete lack of understanding on the subject.
The third misrepresentation is the blatant lack of media coverage for adult stem cells. There have been over 70 different diseases, disorders, or injuries that have been helped or cured with adult stem cells in human trials,{14} yet this has hardly been covered by the media. We have discussed the successes of bone marrow and umbilical cord blood, but where is the media coverage of the latest findings with skin stem cells?{15} Scientists have found ways to coax a patient’s own skin stem cells into acting just like an embryonic stem cell. In other words, these cells have the potential to become almost any cell in the body and they are from the patient’s skin. No use of embryos, no immuno-suppressant drugs, and the technique has been refined for patient safety.{16}
Why this bias? There is a worldview issue at the heart of the matter.
Stem Cells from a Christian Worldview
We have looked at the differences between embryonic and adult stem cells. We have seen the double standard the media has in reporting these types. But the question remains, with all of the successes of adult stem cells, including the ability to create embryonic-like stem cells from the patient’s own skin, why insist on continuing embryonic stem cell research? Why does the debate continue?
I believe a major part of the problem is the answer to the question, Who is in authority? There are two broad options: a God-centered authority or a man-centered authority. The man-centered authority in this case is called scientism. It is the idea that science will save us from our problems and tell what we need to know about life, including what is right and wrong.
Don’t misunderstand me, I am trained as a scientist, and I think studying nature and pursuing scientific questions is important. But when we prioritize science as the only means of gaining knowledge and make it the guide for our lives and the decisions we make, we aren’t studying the world around us, we have essentially invented a religion.
The other perspective is a God-centered authority. In this case all of nature, technology and our decisions are under God’s authority. In other words, we determine what is right and wrong from the Bible because it is God’s revealed word.
Scientists want to continue studying embryonic stem cells, because they want to explore all possibilities, and they see no reason why they shouldn’t. From their worldview, they are in authority. There is no reason to put moral limitations on research. Many people latch onto this idea because they believe science will save them. They have faith in science. Some even believe this to the point of claiming stem cells will cure diseases and ailments that no stem cell therapy could ever do.{17}
Some scientists argue that we need to study embryos to better understand how a disease can develop in the earliest cells. These studies have been done in animals, but scientists would prefer to use humans because there are several developmental differences between humans and other animals.{18}
As Christians, we believe scientific study and finding cures for diseases is a great endeavor. But just because we can do something, doesn’t always mean we should. We know what we should do from God’s word. He values the unborn, and values human beings as having inherent dignity because we are made in his image. We therefore cannot judge some humans less valuable than others, and we certainly cannot destroy them for research observations or for removal of their parts. From this perspective, adult stem cell research is ethical, but embryonic stem cell research is not.
Notes
1. An excellent documentary on the basics of stem cells and the controversy around embryonic and adult stem cells: The Lines that Divide: The Great Stem Cell Debate. Dir. Brian Godwana. The Center for Bioethics and Culture Network, 2009. See this link for a clip: www.thecbc.org/redesigned/research_display.php?id=373.
2. “Purification and characterization of mouse hematopoietic stem cells.” GJ Spangrude, S Heimfild, IL Weissman, Science Vol. 241, Issue 4861, 58-62.
3. www.nationalcordbloodprogram.com
4. www.foxnews.com/story/0,2933,392061,00.html
5. www.stemcellresearch.org
6. www.geron.com/grnopc1clearance/
7. “Survival and proliferation of non neural tissues, with obstruction of cerebral ventricles in a Parkinsonian patient treated with fetal allografts.” Neurology, Vol 46, Issue 5, May 1, 1996.
8. www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1000029
9. “Functional skeletal muscle regeneration from differentiating embryonic stem cells.” Nature Medicine 14, 134-143, 2008.
10. See Executive Order 13435; for an excellent article on the politics of stem cell research from a Christian worldview, see “Responsible Science & ESCR” by Greg Koukl in Solid Ground May/June 2009 (a publication of Stand to Reason).
11. www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1864811 (Journal of Spinal Cord Medicine 29, 191-203, July 2006).
12. www.lifenews.com/bio2751.html; www.bio-medicine.org/medicine-technology-1/Groundbreaking-Paper-Publishes-Long-Term-Results-of-a-Successful-Phase-I-Clinical-Trial-Using-Autologous-Neural-Stem-Cells-to-Treat-Parkinsons-Disease-3848-1/; www.bentham-open.org/pages/content.php?TOSCJ/2009/00000001/00000001/20TOSCJ.PDF
13. For an excellent overview of Alzheimer’s, see the Alzheimer’s association website at www.alz.org; for their statement on stem cell research see: www.alz.org/national/documents/statements_stemcell.pdf.
14. “A 37-year-old-spinal-cord-injured female patient, transplanted of multipotent stem cells from hum UC blood, with improved sensory perception and mobility, both functionally and morphologically: a case study.” Cythotherapy 7, Issue 4, 368-373, 2005.
15. One person in the popular media who did mention skin stem cells was Dr. Mehmet Oz on the Oprah Winfrey Show: www.youtube.com/watch?v=lDFJOzu9SyM.
16. K. Takahashi, et al., Cell doi: 10.1016/j.cell. 2007.11.019; 2007; J. Yu, et al., Science doi: 10.1126/Science. 1151526; 2007.
17. See Joseph Bottum and Ryan T. Anderson’s article in First Things for an excellent reference on the history of stem cell research: www.firstthings.com/article.php?year=2008&month=10&title_link=001-stem-cells-a-political-history-27. Also see Anderson’s article in the Weekly Standard for reasons scientists still want to study embryonic stem cell research: www.weeklystandard.com/Content/Public/Articles/000/000/016/258hdaij.asp?pg=1.
18. The scientists who conducted the research on skin stem cells that were coaxed into acting like embryonic stem cells did use knowledge from embryonic stem cell research to help identify the general markers for pluripotency. However, it is unclear that it is necessary to use human embryonic stem cells for this, because the markers for pluripotency were first identified in mouse embryonic stem cells.
© 2009 Probe Ministries