01-04-2009 - Traces, n. 4

society
STEM CELLS AND ideology


The Facts Speak for Themselves
Remember Barack Obama’s words announcing new public funding for research on embryonic stem cells? “We make scientific decisions based on facts, not ideology.” All right, then. We examined what truly emerges from the most advanced studies on the topic and discovered that, once again, the true problem is in the use of reason.

by Marco Bregni*

On March 9th, Barack Obama, President of the United States, issued an executive order authorizing federal funding for research on stem cells obtained from human embryos, thus overturning the 2001 Bush Administration provision banning federal funding for this type of research. It is important to note that research on embryonic stem cells wasn’t banned. It was limited to already existing cell lines and financing from private non-governmental agencies and individual states, such as California. Obama accused the previous government of having acted ideologically, and made himself the champion of the freedom of scientific research and choices “based on facts, not on ideology.” The new provision will make it possible to generate human embryos in the laboratory for the one purpose of deriving stem cells from them, and will give the green light to human cloning, that is, the creation of embryos with the genetic patrimony of a unique individual in order to obtain “compatible” stem cells.
That the new American President had no ethical qualms about authorizing even the most questionable biotechnologies was already evident just three days after his election, when the Food and Drug Administration sanctioned a pilot study on therapy with embryonic stem cells for the reconstitution of spinal marrow damaged by grave trauma. This is a “Phase I” study, that is, it is meant to evaluate the therapy’s safety, not its efficacy, and will involve 8–10 patients. The FDA had sent back this very study six months earlier because of the insufficiency of data about its clinical application. It’s truly surprising that in just six months all the missing data has been produced. This authorization is particularly serious considering that in an analogous experiment in Russia (granted, with inadequate methodology and controls), one of the patients treated developed a spinal marrow tumor from the transplanted cells.
What are stem cells, and why are they so important? Is it true that their use could cure some of the gravest and most debilitating clinical conditions, such as Parkinson’s, Alzheimer’s, and cancer?

Two properties. As is well known, there are two types of stem cells, adult and embryonic. Adult stem cells were initially identified in the 1960s in the bone marrow, but they exist throughout the human body and have been defined on the basis of two fundamental properties: the capacity for self-renewal and the capacity to generate a great quantity of other cells, with different characteristics and functions. It’s intuitive that the cells of our body that age and die must be replaced in order to maintain the integrity and functioning of the organs. Stem cells are the “progenitors” of all types of cells; in and of themselves they carry out no particular functions, but are able to produce various cell types that specialize in one or more functions. For example, in the case of blood cells, the red blood cells specialize in transporting oxygen, the white blood cells in defending the organism from infections, and the platelets in protecting it from hemorrhage. Stem cells are not numerous (fewer than one in ten thousand in bone marrow) and are difficult to identify because they lack definite functional characteristics. They are therefore termed “undifferentiated” and “pluripotent” to point out their capacity of proliferation. To date, stem cells of various organs and tissues have been identified–for example, those of the liver, muscle, intestine, cornea, and nervous system–but it is probable that all the organs of the body have stem cells, and that their discovery is only a matter of time. At the same time, another property of adult stem cells has been identified: plasticity, that is, the capacity to develop into different cell lines. For example, brain stem cells can give rise to blood or muscle cells, and vice versa.
Current scientific evidence makes it clear that the potential use of adult stem cells is enormous, since they have the capacity to rebuild organs damaged by trauma or degenerative diseases, such as the myocardium destroyed by a heart attack, the nervous system impoverished by Alzheimer’s, or bone tissue lacking in victims of multiple traumas. However, the many technical problems in identifying, isolating, and preparing stem cells for clinical use are such that their use is still, for the most part, experimental. In clinical practice, only hematopoietic stem cells, that is, those derived from bone marrow, are currently used, because of the relative ease of obtaining them and the ability to conserve and manipulate them in the laboratory. These stem cells, used to treat various blood diseases and some tumors of the adult and child, can come from bone marrow, peripheral blood, or umbilical cord, for which there are now many banks around the world.

Mirages in the test tube. Embryonic stem cells are more undifferentiated and can produce almost all the tissues of the body. A few days after conception, the embryo is like a hollow sphere, at the center of which is the so-called inner cell mass, which gives rise to the body of the adult man. Removing this aggregation of cells means damaging or destroying the embryo, thus eliminating a life. In addition, there are two biological problems in the use of embryonic stem cells: the onset of tumors due to the uncontrollable proliferation, and rejection due to incompatibility with the person being treated.
The point is that there is no scientific data today documenting the efficacy of therapy with embryonic stem cells. Scrambling after the mirage of creating a new human being in the test tube, many laboratories throughout the world have tried, but none have succeeded. In 2005, Science published the work of a South Korean researcher who claimed to have obtained embryonic stem cell lines by nucleus transfer, but his assertions turned out to be a colossal fraud.
It is difficult to see the motive for persisting in a line of research that necessarily implies the sacrifice of human embryos without tangible clinical results, if not for the enormous profits that the pharmaceutical and biotechnological companies can derive from patents and commercial exploitation. Obama’s announcement capitalized on public opinion in insisting on the need to alleviate the suffering of the sick, forgetting that the only clinical applications of stem cells today are those of adult stem cells. With great clarity, the Chairman of the United States Conference of Catholic Bishops Committee for Pro-Life Activities, Cardinal Justin Rigali, said that “President Obama’s new executive order… is a sad victory of politics over science and ethics. This action is morally wrong because it encourages the destruction of innocent human life, treating vulnerable human beings as mere products to be harvested.… Finally, it ignores the fact that ethically sound means for advancing stem cell science and medical treatments are readily available and in need of increased support.” In fact, Shinya Yamanaka, a Japanese researcher, recently demonstrated that it is possible to generate undifferentiated stem cells from adult stem cells, that is, similar to embryonic ones without the collateral effects attributable to the latter, an assertion confirmed by numerous other researchers. Science magazine deemed this discovery the most important one of 2008.

Other roads. So then, there are tools for reaching the goal that do not damage embryos and that are more scientifically sound than the research on embryonic stem cells. The human and thus scientific position expressed by the Church better comprehends and faces the research on stem cells than that of Obama: reality cannot be fully understood if one fails to use all the possibilities made available by reason, or if one attempts to impose one’s prejudices on reality (that is, the method is imposed by the object). As the Pope said in Regensburg: “The scientific ethos, moreover, is the will to be obedient to the truth and, as such, it embodies an attitude which belongs to the essential decisions of the Christian spirit. The intention here is not one of retrenchment or negative criticism, but of broadening our concept of reason and its application.”

*Director of the Oncology Department, San Giuseppe Hospital, Milan (Italy)