Stem Cell 1

A stem cell is a unique cell type that can heal itself, regenerate, and can transform into alternate types of cells. Simply put most cells in the body can only complete a single function. Such as a heart cell is used only for heart function or a skin cell similarly used only in skin function. A stem cell does not have this restriction and does not commit itself to a single function until signaled to develop into its special cell function. The ability of a stem cell to regenerate and remain viable in its noncommittal state, makes stem cells unique (Panchision, 2009). Scientists have tried to find the route to replacing damaged cells for many years. The use of animal and adult stem cells has been the source of the research for years. What has changed is the finding that there is a certain category of stem cells that may be able to transform into any type of cell in the human body. This category is pluripotent or able to regenerate into the over 200 types of known cells in the body. The finding of this cell type is within embryonic tissue.

Stem Cell research has undergone tremendous scrutiny in recent years. The interest is in the study of specific stem cells that can reproduce cells and tissue that has been harmed or destroyed. These cells may be able to regenerate healthy tissue, organs and limbs so that we can repair bodies that have suffered with disease, organ malfunction, or loss of limbs (Panchision, 2009). There is much controversy due to the source of stem cells. Either embryo or adult cells are required. With Embryo stem cells it is required that the cells be removed from an embryo that has been fertilized in a laboratory setting. That requires the destroying of a blastocyst or embryo, this to many is stepping into immoral territory that trivializes the sanctity of human life (Mehlman, 2005).

Stem cells can also be derived from fetal tissue, umbilical cords and the placenta. The fetal stem cell comes from an aborted fetus. A fetus is a human baby that is several weeks old in the womb. Stem cells can also be harvested from the blood of an umbilical cord of a baby that has been born. The placenta carries stem cells within it. The cells can be extracted from the placenta of a newborn baby. There are currently two different types of fetal stem cells that are identifiable. One is Pluripotent stem cells and the other is Hematopoietic stem cells. Pluripotent stem cells are found in the fetus itself and hematopoietic stem cells are found in cord blood. According to Maze Cord Blood, “Pluripotent stem cells that are present in embryos are the most basic stem cells. Since they are so primitive (or undifferentiated) they can actually create and form new tissue and new organs. This is what makes them so medically useful. Because they are found within the fetus itself, the use of them is controversial.” The fetal stem cells found in the baby's cord blood, which are hematopoietic stem cells, are different. They are not as primitive as the pluripotent stem cells since they have already started to become blood stem cells. In saying this, they can create new blood for patients. The stem cells found in cord blood have been used to regenerate new blood in patients who have blood diseases. Obviously, the uses for hematopoietic fetal stem cells have really grown dramatically over the years. (Maze Cord Blood, 2008)

Figure 1. Blastocyst Development. (Winslow, 2001).

In addition to this newfound information, researchers discovered another category of stem cells as well. This category came from the adult stem cells. This adult stem cell also has the property of regenerating itself and remains viable in an uncommitted state as to the type of cell it is to become until signaled to develop. It has been found that the adult stem cells from one tissue may be able to take on the qualities of the same (multipotent) or other tissues (Panchision, 2009). This concept in adult stem cell research is termed plasticity. Though there is the alternative of the adult stem cell and this is more easily accepted. However, there are drawbacks to this method as well. A discussion of the advantages and disadvantages of stem cell research will pull out the details for a better understanding, and are below:

Advantage of Stem Cell Research

  • It may be the cure for many diseases such as Parkinson's, Multiple Sclerosis, and Alzheimer's. These diseases occur due to loss of nerve cells in the brain. These nerve cells transmit neurons in the brain and throughout the body using dopamine (Pillai, 2008). This neurotransmitter controls the spine, and affects mental and physical coordination. If stem cells can reproduce this dopamine successfully, it could be possible to regain nerve function within the body (Panchision, 2009). This type of testing on humans is not yet available.
  • It holds promise to benefit regenerative medicine.

Figure 2. (Winslow, 2001).

The loss of cells of the nervous system causes serious illnesses that affect the brain's ability to function. There are cells such as the oligodendrocyte that increases the speed at which neurons are signaled along the spinal cord. See Figure 2 The Neuron (Winslow, 2001).Recent research on mammals has tied information about adult stem cells found in the adult brain able to regenerate these neural cells. It is the hope that they can grow new cells to replace those damaged or diseased in the brain. It is now known that "new neurons in the adult brain arise from slowly-dividing cells that appear to be the remnants of stem cells that existed during fetal brain development'. Thus defining adult neural stem cells (Pillai, 2008).This discovery is huge in adult stem cell research as it implies that the adult brain possibly has the capacity to heal itself. Since finding these cells, researchers are busy seeking out how to get these cells to reproduce healthy cells to replace the damaged cells caused by disease. The diseases that may be affected by such a breakthrough are Lou Gehring's Disease, Huntington's Disease, Parkinson's Disease, and those caused by spinal injuries (Stemcell.umn.edu, 2004).

Researchers at Berkeley in California have found a key to reversing the effect of aging in mice. It appears there are two ways in which adult stem cells react to repair tissue damage. Depending on the age of the subject. In this case mice. The adult stem cells were adapted to respond to chemical signals that activated the muscle tissue in older mice to respond in the same way as young mice (Pillai, 2008).

  • The use of adult stem cells as the subject would be using their own cells, which reduces the change of rejection of the organ.
  • The ability to regenerate organs would allow the testing of new pharmaceuticals on human tissue without human or animal testing.

Figure 3. In Vitro Fertilization(Mehlman, 2005). Figure 4. Sperm Fertilization of the Egg (Mehlman, 2005).

Disadvantages of Stem Cell Research

  • In order to conduct embryonic stem cells, the newly conceived embryos in the lab must be destroyed (Pillai, 2008). This is a moral question, that in fact condones the destruction of a viable, and albeit innocent human life for science.

As far as a precedent for which to settle the dispute or at least support it. Immanuel Kant during the time of the Constitution put forth a principle called the Categorical Imperative. It states that people are to be treated as ends "rather than as means". Also our Declaration of Independence also states that we have rights as individuals to life, liberty, and the pursuit of happiness (Mehlman, 2005). Scientists and commentators alike believe we have a responsibility to respect human lives from the moment of conception (Moynihan, 2003).

  • There may be side affects from implanting organs into humans that we are not aware of. The long-term repercussions of this intervention with natural events is unknown (Pillai, 2008).
  • Stem cell research with heart disease has found the coronary arteries to be narrower in the subjects than the original cells (Pillai, 2008). This may result in a recurring or unknown side affect that may be similarly threatening to the patient as the original disease.
  • Embryonic stem cells are taken from a foreign body and transplanted to the patient. The patient's body may reject the organ or treatment (Pillai, 2008).

Recent Developments Embryonic Stem Cells No Longer Required

The controversial embryonic stem cell research may no longer be necessary. There are three distinct studies that have concluded that skin cells can be reprogrammed into an embryonic state (Deem, 2007). This state is what we call the pluripotent stem cell. That is found in the blastocyst. Studies have been done on both mice and human skin cells. The process is called induced pluripotent stem (iPS) cells. Though there is still more work to be done. The process has been successful and further research will most likely reduce the number of issues surrounding the production of viable stem cells from human skin cells (Deem, 2007). According to the James Thomson study, "The human iPS cells described here meet the defining criteria we originally proposed for human cells, with the significant exception that the iPS cells are not derived from embryos" (Thomson, 2007).

One of the most often asked question and issue surrounding this discussion of Stem Cell Research refers to what diseases have been treated by Stem Cells

To date the only human treatment of stem cells is with adult stem cells in bone marrow. Termed hematopoietic stem cells, they are current used in treatment of diseases such as leukemia, and blood diseases (Deem, 2007).There is also a treatment for heart disease called "VesCellTM Therapy. It involves treating stem cells taken from the patient, processed, and then given back to the same patient" (Vescell.com, 2009). This treatment is available in Bangkok and has not been approved by the FDA in the U.S.The associated conditions for which Ves Cell has been suggested are congestive heart failure, coronary artery disease, and those that have already had triple bypass surgeries. It is considered one of the last options of the patient who has been given only a few years to live (Vescell.com, 2009). Moreover, the following table discusses the types of embryonic and adult stem cells and their advantages versus disadvantages.

Table 1 Types of Stem Cells (Deem, 2007)

Table 2 Stem Cell Sources (Deem, 2007)

Overall, the advent of Induced Pluripotent Stem (IPS) cells from skin cells may be the answer that will provide the needed solution to so many debilitating diseases and conditions that affect millions of people around the world. This will remove all controversy surrounding the destroying of the blastocyst or human embryos and fetuses to obtain stem cell tissue. Recently, cord blood research has discovered evidence that suggests that, under the right circumstances, cord blood may be conditioned to "change" into the building blocks of organ tissue. If that is the truly the case, then the potential uses of cord blood stem cells will be extraordinary, including treatment for everything from breast cancer to heart disease to diabetes. The use of stem cell will have an extraordinary effect on so many things that need to be changed.Moreover, let us hope this new research is the final answer.

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