I have been doing quite a bit of research about this particular topic for many reasons. One important reason though is that a friend of mine is struggling to do everything in her power to save her baby's life as her child is affected by a rare disease known as biliary atresia. There are many treatments available for children with this affliction but none have proven to be very successful about in treating this disease - except with the hope of stem cells. I normally don't tackle a very sensitive issue like this as a lot of controversy surrounds this particular topic but I'll try to present this as neutrally as possible.
Here are the things that I have found out about stem cells.
Let us start with six facts about stem cells:
There is no "ban" on human embryonic stem cell research in the United States.
This has been arguably the most muddled point in the entire debate. ESC research goes on at labs throughout the country, with no legal barriers to prohibit such research or the private financing of it. The federal government has funded ESC research to the tune of $130 million dollars since 2001, and the U.S. continues to be the international leader in the field. Out of all peer-reviewed research papers published from 1998 through 2005 on original human ESC research, scientists from the U.S. published by far the most, 125 of the 315.
We are a long way away from therapies derived from embryonic stem cells.
James Thomson, the first scientist to derive stem cells from a human embryo, made this point clearly just a few weeks ago: "I don't want to sound too pessimistic because this is all doable, but it's going to be very hard." He added, "those transplantation therapies should work but it's likely to take a long time." Leading British stem cell expert Lord Winston has been even more blunt: "I am not entirely convinced that embryonic stem cells will, in my lifetime, and possibly anybody's lifetime, for that matter, be holding quite the promise that we desperately hope they will."
There are currently no controlled human clinical trials underway for ESC-derived therapies. By contrast, there are currently some 1200 clinical trials underway associated with human adult stem cells (ASCs). While most treatments derived so far from ASC research apply to blood-related diseases, the broader application of ASCs for a more diverse array of maladies is likely within several more years.
The human embryo has at least some degree of special moral status.
"We believe most would agree that human embryos deserve respect as a form of human life. . . ." So said President Clinton's National Bioethics Advisory Committee, speaking of ESC research. The committee was willing to support the use of "excess" embryos from assisted reproduction clinics, but only if their use was necessary to advance life-saving research. It did not endorse the creation of embryos by cloning or other methods for use in research involving their destruction.
Standard embryology texts insist that from the zygote (single-cell embryo) stage forward there exists a new living member of the species homo sapiens. Surely we can all agree that the human embryo possesses the active potential to develop by an internally directed process towards maturity, and that this is morally significant.
There are non-controversial alternatives worth exploring.
It is increasingly clear that there are non-embryo destructive research alternatives that hold out the promise of providing sources of stem cells with properties equivalent to, or nearly equivalent to, embryonic cells. Such alternatives include, among others, the reprogramming of ordinary somatic (body) cells, the derivation of stem cells from amniotic fluid, and (assuming that it can be shown that the product is not an embryo), altered nuclear transfer.
Concerns about embryo destruction are not only religious.
Charles Krauthammer, a former member of the President's Council on Bioethics, lucidly articulated this point in a Washington Post column: "I don't believe that life -- meaning the attributes and protections of personhood -- begins at conception. Yet many secularly inclined people such as myself have great trepidation about the inherent dangers of wanton and unrestricted manipulation -- to the point of dismemberment -- of human embryos. You don't need religion to tremble at the thought of unrestricted embryo research. You simply have to have a healthy respect for the human capacity for doing evil in pursuit of the good."
While the search for cures is an important motive behind ESC research, it is clearly not the only motive.
Most scientists acknowledge that ESCs will not provide therapies for many years, if ever. Their therapeutic potential is, at best, speculative. They cannot be used now, even in clinical trials, because of their tendency to produce tumors. So it comes as no surprise that many scientists now admit that their primary interest in pursuing ESC research lies not in the hope for direct cell transplant therapies, but in the desire to enhance basic scientific knowledge of such things as cell signaling, tissue growth and early human development.
Here are the Basic Research data that I have uncovered about stem cells:
Stem Cells are the Body's Basic Building Blocks
Stem cells have two unique qualities: they can copy themselves for an unlimited period of time and they can grow into all of the body's different cell types
When a stem cell copies itself, each of the two new cells can either remain a stem cell or become another type of cell such as a muscle cell, a blood cell, or a brain cell.
Some stem cells grow into organs, bones and tissues of the body, but other stem cells work in its immune and repair systems. Called "adult" stem cells, they create replacement cells for those that are lost because of injury, disease or the normal wear and tear of aging.
Adult stem cells can be used for research and treatment, but most researchers believe that "embryonic" stem cells have much more potential to study, treat and cure diseases.
Not all stem cells are alike.
Adult stem cells are called "multipotent." This means they can turn into several different kinds of cells within the same basic cell type. For example, adult stem cells found in bone marrow can turn into all of the different types of cells found in blood. Research on adult stem cells has been funded for over 40 years and many successful therapies have been developed.
Embryonic stem cells are called "pluripotent." This means they can turn into all of the body's cell types except egg and sperm cells. Embryonic stem cells were first discovered in 1998 and research on them has not yet been well funded. Scientists believe that the potential of embryonic stem cells is even greater than adult stem cells.
Embryonic stem cells are blank, unspecialized cells found in the interior of a blastocyst. A blastocyst is a mass of 150 or so cells that is smaller than a period at the end of this sentence. It develops approximately 5-14 days after an egg is fertilized.
Scientists have been able to get stem cells to grow into complex cells with special functions, like the cells of the pancreas that produce insulin or heart muscle cells.
A research process called somatic cell nuclear transfer (SCNT), sometimes referred to as "therapeutic cloning", allows scientists to produce embryonic stem cells without using sperm to fertilize an egg. In this process, there is no implantation in a uterus and therefore no pregnancy.
Using new tools like somatic cell nuclear transfer (SCNT), scientists hope to make cell lines that are specific to a patient and/or a disease. This will help them study diseases in a powerful new way and help them discover better treatments and cures.
Stem Cell Research is Developing Breakthrough Cures & Offering New Hope
- Life-saving stem cell treatments are already successful and in widespread use for some diseases. For example, bone marrow transplants use stem cells to treat leukemia.
- Stem cell research could lead to treatments that save millions of lives and improve the quality-of-life for millions more.
- Scientists are working on a wide range of stem cell-based therapies. They have created "tissue patches" for burn victims. They have grown islet cells that produce insulin to treat diabetes and healthy brain cells to ease the symptoms of disorders like Parkinson's disease. They have genetically changed cells and then used them to deliver healing or protective agents to injured or diseased areas of the body.
Broad Consensus Exists in Support of Stem Cell Research
Stem cell research has strong support by many notable groups including the American Medical Association and the National Health Council.
68% of Americans support embryonic stem cell research.
55% of Texans favor medical research using embryonic stem cells.
70% of Kansas voters want to allow SCNT research in Kansas.
63% of Missouri voters approve of embryonic stem cell research.
64% of Americans support federal funding of research on chronic
In Summary of what I have been able to uncover so far here is what most researchers believe about stem cells and their use in the medical field:
Stem Cells and Human Development Stem cells have enormous potential in health and medical research but to fully harness this potential, scientists are studying how stem cells transform, or differentiate, into the diverse range of specialised cells that make humans what they are today. Because diseases such as cancer or conditions such as birth defects are thought to occur because of problems in the differentiation process, an understanding of the development that happens in normal cells will help scientists treat the developmental errors that can occur.
Stem Cells and Cell-Based Therapies Another potential application of stem cells is to form cells and tissues for medical therapies. Currently, it is donated organs and tissues that are substituted for damaged or dysfunctional ones. Sadly, the number of people awaiting a transplant is much higher than the number of available organs. Transplant waiting lists are enormous and many people die awaiting transplants. Stem cells offer a viable source of replacement cells to treat diseases and can potentially reduce the morbidity and mortality for those awaiting transplants. Some of the areas that stem cells can benefit include:
* Parkinson's disease
* Type I diabetes
* Arthritis
* Burn victims
* Cardiovascular diseases
By directing stem cells to differentiate into specialised cell types, there is the exciting possibility to provide a renewable source of replacement cells for those suffering from diseases.
The potential to reverse diseases is also not a foreign one. For example, a patient who has suffered from a heart attack and sustained heart damage could have the damaged tissue replaced by healthy new muscle cells. The destruction of brain cells in conditions such as Parkinson's disease can hopefully be reversed with the replacement of new, healthy and functioning brain cells. Even more promising is the potential to address genetic defects that are present from birth by restoring function and health with the introduction of normal healthy cells that do not have these defects.
Burn Victims Burn victims tend to endure an enormous amount of pain from their wounds as well as frustration from the challenges of healing. Instead of donor tissues being donated, stem cells could be used to produce new and healthy tissues. This is essentially similar to therapies already being used, such as bone marrow transplants, where stem cells create different specialised blood cells. Scientists aim to locate and remove specific stem cells from a tissue and then trigger them to differentiate outside of the body before transplanting them back into the patient to replace damaged tissues. In burn victims, a very small piece of the skin can be progressively grown, allowing doctors to cover a burn that is often much larger than the original size of the skin piece.
Stem Cells and Drug Testing Stem cells have an important benefit for the pharmaceutical field. New drugs can be tested on stem cells to assess their safety before testing drugs on animal and human models. For example, a cancer cell line could be created to test an anti-tumour drug. If the conditions can be perfectly replicated, testing drugs could provide very accurate results.
The current benefits of stem cell usage are already well documented and it is expected that continued research will pave the way for new treatments. For those suffering from serious diseases, stem cells offer hope for effective treatment or perhaps even a reversal of the disease. Time will confirm the full success of stem cell therapies and continued research should teach us more about using stem cells to treat
Finally here is a video from a notable source to help clear things up a little bit more about Stem Cells.
Introduction to stem cells
Finally everything about stem cells that you were afraid to ask
(this one is a pretty long but quite the most informative video on Stem Cells)
Hope this all helps you out and that in due time things will look better for all of us in terms of health. Till the next time. xoxo
No comments:
Post a Comment