NewWorld

Facing the Stem Cell Controversy in defense of
Reason and Reality

by M. R.

PART I: Getting the scientific facts (with Sara Deola, MD)
Stem cells are particular kinds of cells capable of generating exact copies of themselves as well as more specialized mature cells, a process that happens through multiple steps, even millions. In each step toward differentiation, the cell divides and the resulting cell is more specialized than its “parent.” They work according to the needs of the body: when you get cut, the skin’s stem cells quickly respond, creating extra skin cells and sending them to the injured location.
In order to generate a new body from the few cells of a fertilized egg, embryonic stem cells are tasked with creating the many specialized cells–such as bone, muscle, and brain–that will form that body. The task of maintaining the body once it is born is left to adult stem cells. The capacity adult stem cells have to create specialized cells typically remains within a certain kind of cell. For example, adult basal skin stem cells generate the specialized layers of the epidermis. Adult stem cells remain in the organs for the life of the body, whereas embryonic stem cells disappear after the body is formed.

Treating diseases and injuries
Scientists are hopeful that stem cells could be used to treat degenerative diseases and injured organs by growing and then injecting healthy specialized cells into damaged areas. The key would be accessing the particular stem cells that could generate specialized cells for the damaged organ.

Growing specialized cells from embryonic stem cells
Embryonic stem cells reside in the inner cell mass of the embryo that has formed within about a week of conception. Researchers remove these cells–destroying the living embryo–and then place them in vitro on a layer of “feeder” cells–typically from mice–which sustain them while they are “taught” to form the desired specialized tissue instead of a body.

Strengths and weaknesses
Because adult stem cells are naturally directed toward a specific task, scientists are able to induce them to generate more specialized cells with relative ease. However, for some organs, adult stem cells are scarce, difficult to access, or not yet discovered. Since embryonic stem cells can generate any tissue in the body, some scientists consider them more promising.
However, a number of surprising discoveries suggest adult stem cells have more potential than originally believed. First, the process of differentiation in adult stem cells can be reversed, with cells going backward from having a specialized function to being general. Second, some cells have been observed to cross over into other kinds of cells, as when blood stem cells change naturally into brain cells. Third, researchers are beginning to discover adult stem cells in more organs of the body, which suggests that they remain in the body for more organs than scientists previously assumed.
While embryonic stem cells have much more plasticity than adult stem cells in generating different kinds of cells, they have a strong tendency to form tumors when injected into an organism. In addition, it is not yet understood whether specialized cells derived from embryonic stem cells will “know” how to integrate with the rest of the body, which is essential for proper functioning.

Clinical trials
Only adult stem cells have demonstrated their healing ability in clinical trials. Adult stem cells are currently used clinically to treat many conditions, including leukemia, Parkinson’s disease, and spinal cord injury. In contrast, while scientists have generated several specialized cells from embryonic stem cells, they have not yet successfully used embryonic stem cells in clinical trials to treat humans.1

Somatic nuclear transfer (“cloning”)
Cells that have been coached from stem cells to become, say, pancreatic cells, must now be accepted by another person’s pancreas. As with organ transplants, there are risks of rejection. If it were possible to somehow use an organ made with the patient’s own cells, the risk of rejection would vanish. This is where somatic nuclear transfer, or “cloning,” comes in.
In cloning, the nucleus from an egg is removed and replaced with a nucleus from a normal cell. This triggers the formation of a new life by tricking an egg into thinking fertilization took place, and that now it is time to develop the body. Even eggs from another species can produce a human clone. Amazingly, what grows out of that transfer is a creature with essentially the same genetic features of the nucleus you inserted, such that if you insert the nucleus of one cell of “Joe” into a monkey’s egg, a clone of Joe will grow from this embryo, if implanted into a uterus. However, DNA from the human or animal egg used will be present in all Joe Clone’s mitochondria.
If embryonic stem cells were found useful in clinical trials, then the inner stem cells from the “Joe Clone” embryo could be extracted and specially grown into, for instance, neural tissue. If Joe later developed Parkinson’s disease, that neural tissue may be able to contribute to his treatment without risk of rejection.
Therapeutic and reproductive cloning
There is no difference between clones created for therapy and clones created for reproduction. In both cases, a new embryo is created. The difference lies only in what is subsequently done with the cloned embryo. If created for reproductive purposes, it would be implanted in a uterus and allowed to develop. If created for therapy, the embryonic stem cells would be extracted according to the procedure described above, destroying the embryo.

PART II: Reviewing
the Legislation
Currently, no federal legislation restricts embryonic stem cell research in the United States.
The legislation under debate in recent months pertains to the use of federal funds for human cloning and embryonic stem cell research.2
Between 1997 and May 2005, ten states enacted laws banning human reproductive cloning, and two passed legislation prohibiting state funding of human reproductive cloning. However, the real story is told by the many bills and resolutions currently pending in over twenty state legislatures across the country, as well as the number of states that have not enacted proposed legislation that would ban research on human cloning or embryonic stem cells.

Part III: Would you be
happier...?
Why is there such an insistence on embryonic stem cell research and human cloning? For some, it is the attraction of creating life, generating creatures with features we would determine. For others, it is the desire that the person they love not suffer and die. Many insist on using embryos in this way because it seems the sure road to happiness.
But what does it mean to face this issue without censoring our reason and our desire for happiness? We can start from the most evident fact: I exist. I did not make myself, and yet I am here. The same is true for the embryo: it exists. So what am I? Why am I here? Even if I am able to reproduce an embryo in my laboratory, what is it that I am reproducing?
Each of us, looking at our experience, can see that we are more than a mass of cells, whether there are eight or millions of them. My desire, my love, my fear, my longing cannot be defined as a mass of cells. When we suffer because those we love are sick, when we do everything we can to save them, even to the point of killing somebody else (an embryo), why are we doing this? Is it a mass of cells that we love?
This experience of love, desire, and longing tells us that we are greater than our appearance, than our physical composition. We are a mystery to ourselves. When we arrive at this awareness, the confusion lifts and we see clearly that we cannot do as we wish with another human being because, like each of us, this other is great, mysterious. These days, scientists are commonly cited as appropriate authorities on the morality of stem cell research. However, science is a tool for dealing with physical, measurable realities, and is unable to provide us with a criteria for deciding which scientific endeavors to pursue, for which purposes. These decisions require a judgment based on value, and a judgment based on the inherent value of the human person recognizes that human beings can never be instrumentalized for any purpose, no matter how noble.
The insistence on using embryonic stem cells, together with all the efforts to make the issue abstract with technical terms, are poor attempts to avoid the fundamental questions: What am I? What is the purpose of my life? What is it that burns in me, continuously? 
We cut short these fundamental questions when we abdicate our judgment to what science measures and power sanctions, or even to the images we construct of what will make us happy. The ultimate questions that this issue raises so strongly in so many of us are instead a tremendous resource. Much more than a political or scientific problem, the provocation of embryonic stem cell research is an occasion to regain an awareness of the mystery of our being, to discover again what it really means to say “I.”

Notes

1 We found only one published study that attempted to use cells derived from embryonic stem cells. These researchers examined the safety and feasibility of implanting embryonic-derived cells into brain stroke patients. After 2 years, the implanted cells had not formed tumors in those patients; however, no clear improvement in their stroke condition could be documented. Kondziolka, D., et al. (2000). Transplantation of cultured human neuronal cells for patients with stroke, Neurology, 55, 565-569.
2 For a history of US federal funding for stem cell research, see the President’s Council on Bioethics 2004 report, “Monitoring Stem Cell Research”
(http://www.bioethics.gov/reports/stemcell).