Stem Cells and Therapeutic Cloning
Essay by review • December 18, 2010 • Research Paper • 3,437 Words (14 Pages) • 1,294 Views
Stem Cells and Therapeutic Cloning
Embryonic stem cells were grown in a laboratory successfully in 1998. At that time researchers were able to have the stem cells begin copying themselves without becoming anything further (Easterbrook, 2000). This was an exciting time for researchers to begin discovering this new technology. The therapeutic cloning process begins when the nucleus is removed from a human egg and replaced with the nucleus of a body cell from the person who needs to be treated. The resulting hybrid cells can be grown outside the person's body in a laboratory. The cells divide to form a collection of cells called a blastocyst, which is essentially the early stage of a human embryo. The cells in the blastocyst are called stem cells, because unlike most of the cells in the human body, they are not yet specialized to carry out particular jobs (K.E. Hammel, PhD., personal communication, April 23, 2006). That is, if these cells receive the right instructions, more specialized cells can stem from them as they continue to divide. This paper is written to support the efforts of research to improve the quality of life for individuals that may benefit from advances in regenerative medicine through the use of stem cells in therapeutic cloning. One of the promising features of stem cell therapy is that the cells resemble those of the patient so closely that he or she will not be rejected by the immune system.
Ethics
Ethical questions arise when stem cells are obtained from human embryos, and some find this morally repugnant. In the article Public Perception and Cloning and Embryonic Stem Cells, Turnpenny (2005) states one of the ethical controversies is in regard to the word cloning and for the implied destruction of a human life. Much of the controversy is over when life begins, which is a question that is not easily answered. Another aspect is the perception that human cloning is possible, and cites Dolly the sheep as an example. Turnpenny is convinced the media has influenced the public by reporting a biased and sensationalist portrayal.
Improve Treatments
Promising research in regenerative medicine that would treat of spinal cord injuries, organ regeneration, leukemia treatments, and degenerative diseases have proven to be successful and offer hope to many.
Regenerative Medicine
Regenerative
If a person has had a spinal injury, the nucleus of a healthy cell from some other part of their body might be injected into an enucleated egg. The resulting stem cells could be injected into the site of injury in the hope that they would specialize into new nerve cells that could grow. Alternatively, it might be possible to induce the stem cells to specialize into nerve cells in the test tube, and inject them into the patient. Scientists in South Korea recently helped a paraplegic to walk after being injected with cloned stem cells. The man had been unable to walk for 19 years; the experience has dramatically changed his quality of life. This type of success has been show in mice during clinical trials.
Tissue regeneration through cell replacement therapies is being considered for heart transplant patients. Heart transplants have been (Vats, 2005) occurring successfully since 1967. The problem is in the shortage of available organs and the inability to meet the continued demand for these organs. Cell replacement therapies would be used to repair hearts much in the same way bone marrow transplants and treatments for leukemia have been used.
Disease
Oncogene, the gene associated with leukemia, can transform white blood cells into leukemia cells. Certain leukemia oncogene governs self-renewal which is one of the unique characteristics of stem cells. This new information might explain why the cancer drug gleevec which targets the BCP-ABL enzyme does not cure cancer and is only able to put cancer in remission. Research focuses targeting the additional abnormal growth pathway which is necessary to cure chronic myeloid leukemia. Researchers target cancer stem cells therapeutically. Cancer stem cells are the important target of therapy believed to be the main reason that cancer patients relapse. The process changes normal cells to act like stem cells. This gives medical research new tools to target the genetic programs that enable leukemia genes to self-renew. This new research now may be able to switch on these programmers in normal cells to trigger tissue regeneration.
Baby mice gave researchers new hope to cure Parkinson's disease and other degenerative disorders using neural stem cell in transplants 1999. In new updated studies (2000) Dr. Snyder and his colleges inject baby mice with neural stem cells from mutant stain that developed tremors within the first few weeks of age. These Tremors are caused by a lack or protein that makes myelin which insulates and coats the surrounding nerve fibers (Snyder, 2000). These mice have shown the same effects that humans display caused by a short supply of protein in the brain. Researchers compare transplant results of mutant baby mice to normal baby mice and found stunning remarks; that seems the transplanted neural stem cells attacked the damaged cells in the mutant mice and began to take over repairing, and replenishing cells stopping over half of the tremors in the mutant mice. Even though there is a break through with transplanting neural stem cells in baby mice, there has been no evidence proven that the transplant will have the same effect on younger mice to adult mice. Scientists agree that additional research is necessary.
Research shows that the use of embryonic stem cells is a controversial issue because of the debate over the life of the embryo. In the research, Lee Turnpenny, Ph.D., and Gregg Easterbrook have differing views on the status of embryos. Turnpenny (2005) writes that embryonic cells "are not derived from embryos, but from laboratory quasi-embryos". He further explains that a quasi-embryo is an embryo that is not attached to the womb, therefore; not having real life. Gregg Easterbrook writes in Stem Cell Research and Human Cloning: An Overview (2000) that his work on embryonic cells is performed on embryos during the first week they were conceived in in-vitro fertilization. He believes at this early stage there is no consciousness. Turnpenny does not consider the embryo to have real life since it is not attached to a womb, where Easterbrook does not consider an embryo to be conscious until it is nine weeks or older. There was no evidence of propaganda in these papers which were written by authors associated with universities in the United States and the United Kingdom. Gregg Easterbrook is a biologist
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