February 7, 2013
Improved Health Prospects through Cloning of Stem Cells
Whenever the word cloning is mentioned, various reactions are provoked. For many, this process belongs to the realm of science fiction while for some, it is a morally wrong process. There are those, though, who painstakingly keep track of its progress because it holds the possibility of cure.
Stem Cell Cloning Today
The cloning of stem cells today has taken on a more pragmatic and less conflicted mantle. The objective of growing a full human being from a Petri dish is not at all what is happening in laboratories because the procedures and the purposes involved have become research and therapy centered.
Embryonic stem cells used in the laboratory do not come from a woman’s body. Instead, they are produced in the laboratory through Somatic-cell Nuclear Transfer. In the simplest of terms, the procedure involves taking an unfertilized egg cell (which becomes the host), removing its nucleus then fusing the nucleus from a somatic cell. When the somatic-cell nucleus is inserted into the host egg, two things happen: the nucleus is reprogrammed; the host is stimulated and begins to divide. The single cell then develops through mitotic divisions into a blastocyst which has from 100 to 200 cells. The inner cell mass of this blastocyst, made of embryonic stem cells, is then extracted.
The cloning of stem cells in this manner yields human embryonic stem cells which are commonly referred to as hESCs. These stem cells are extremely critical in future treatment protocols because they are pluripotent, meaning they can differentiate into virtually any type of tissue. Because of this, they potentially lend themselves to therapy more easily than multipotent stem cells which are committed to differentiating into a limited variety of cells.
Importance of Cloning Stem Cells
Although stem cells can be obtained from the bloodstream, from bone marrow and from umbilical cord blood, these stem cells have limited capacity to differentiate into various cell types. Embryonic stem cells, however, are a blank slate; they are uncommitted and have the potential for producing whatever cells are needed. In addition, when transplantation is done, there is a possibility of tissue rejection with stem cells (as against eHSCs). This gives rise to the possibility of host-versus-graft-disease.
There are numerous reasons for the clamor of support for cloning stem cells. One of these is the fact that there is a severe shortage of organs for transplantation. Per year, less than ten percent of patients needing organ transplants receive matching donors. This discrepancy is expected to grow with the passing years.
Even if donors are found for patients needing transplants, these recipients still have to worry about organ or tissue rejection. Usually they have to be on immunosuppressive medication for the rest of their lives which makes them prone to infection. With stem cell use, the chances for such rejection are much reduced.
Potentially, stem cells, particularly hESCs, can radically change the prognosis for some diseases for the better. Among these diseases would be Alzheimer’s disease, Parkinson’s and other degenerative diseases but an even more practical application would be in the case of a stroke. Recovery from a stroke would have better probabilities if it were possible to use hESCs to replace the brain cells that have been damaged during the stroke. The same would hold true for people who go through heart attacks; instead of scar tissue, the heart would be able to grow new tissue.
Concerns in Relation to Cloning of Stem Cells
The fundamental ethical concern in relation to stem cell cloning revolves around the question of when life starts. This is a grave moral dilemma which reverberates in legislation and state funding. Scientists assert that the acquisition of embryonic stem cells through Somatic-cell Nuclear Transfer does not deprive any being of life. Some also state that the extraction of the hESCs is done when the blastocyst has not differentiated; no organs have been formed and life is not yet viable. In fact, the term pre-embryo is used quite often in literature about stem cell cloning.
Perhaps with new technology more methods can be discovered to extract stem cells without running into the problem of whether or not life has been extinguished from an organism with the moral status of a human being. When that happens, it will be a truly welcome occasion for many.