Category Archives: Embryonic Stem Cells

Embryonic Stem-Cell Research Reaches Moral, Medical Dead End

Ethical adult stem cells have a proven track record of success. Why, then, asks researcher David Prentice, is the NIH still spending $250 million a year killing embryos?

Published, peer-reviewed clinical trials have shown stem cells have reversed stroke damage years after the injury, helped spinal-cord-injury victims regain lost movement, helped heart attack patients recover, cured sickle cell anemia and reversed a wide range of diseases, including multiple sclerosis, type 1 diabetes and lupus erythematosus.

Advances with ethically sourced adult stem cells have already helped more than 1 million patients, according to a recently published review paper by David Prentice, a research director for the Charlotte Lozier Institute and a former professor of medical and molecular genetics at Indiana University School of Medicine.

He calls adult stem cells the true gold standard of regenerative medicine, while nearly two decades of media hype and the infusion of billions of research dollars on stem cells culled from human embryos have produced exactly zero published reports of validated success in a single patient.

Actually, its probably closer to 2 million patients that have been treated with adult stem cells now, Prentice told the Register. The 1 million figure he cited in his paper is from 2012, and the field of stem-cell research has exploded since then.

The Virginia-based Charlotte Lozier Institute has been trying to raise awareness about the successes of adult stem-cell therapies, against a mainstream media that seems to ignore them while championing more research on embryos. The institute has produced a series of videos featuring patients who have recovered from a wide range of diseases, including some of the most debilitating brain injuries and autoimmune diseases that have become epidemic.

Stroke Repair

One of the stories they tell is that of Sonia Coontz. She didnt realize she was having a massive stroke in May 2011 because she was only 31 years old at the time. During the day she suffered the stroke, the Long Island dog trainer noticed that different words came out of her mouth than the ones she wanted to speak. By evening, her husband, Peter, noticed that half her face had fallen slack. Later, she was struggling to move her arm and her leg, but she knew she was in real trouble when she tried to call Peter but couldnt say his name.

Doctors told Coontz the stroke damage clearly visible as a large, white mass on her brain scans was irreversible, and she would be severely disabled for life. For two years, this diagnosis proved accurate; Coontz could speak only 20 words, she couldnt move her right arm more than a few inches, her shoulder was in constant pain, and she could not walk more than five minutes without needing a wheelchair. She sank into depression.

Two years after her major stroke, when she was considered well beyond any hope of further recovery, Coontz heard about stem-cell trials at Stanford University. She became one of 18 patients enrolled by neurosurgeon Gary Steinberg to undergo a transplant of bone marrow stem cells directly into her brain, next to the area of her stroke damage.

Almost immediately after the surgery, Coontz was able to raise her paralyzed right arm over her head. Her voice became stronger and her language returned. She now runs, climbs stairs and has had a baby.

He has given me a new life, she said of Steinberg when she presented him the Smithsonian American Ingenuity award for his work in 2017.

Not all of Steinbergs patients experienced as miraculous improvement as Coontz did, but several had clinical improvements, and the clinical trial revolutionized the understanding of the brains potential for post-stroke recovery and the potential of stem cells to induce that recovery. It also spurred on dozens of other researchers looking to help the more than 800,000 annual American stroke victims, as well as those using stem cells to treat traumatic brain injury and neurodegenerative diseases such as Alzheimers and Parkinsons.

Lupus and Multiple Sclerosis

Other stem-cell recipients include Jackie Stollfus, who suffered from lupus erythematosus, an autoimmune disease that has recently become the leading killer of young women in America.

Stollfus immune system had begun attacking her own cells, and she was suffering from arthritis and kidney failure and was barely able to get out of bed. She miscarried her first baby because of complications of the disease. Stollfus underwent chemotherapy to obliterate her own immune system and then had filtered stem cells from her own marrow transplanted in a clinical trial by Dr. Richard Burt at Northwestern University.

Seven years later, she has no sign of lupus, and she has given birth to two healthy baby girls.

Burts research has also been researching adult stem-cell transplants in patients with multiple sclerosis; and his study published this year, of 103 patients, found that only three of those who underwent stem-cell therapy progressed further into disease compared to 34 of those getting standard treatment. And most stem-cell patients showed clinical improvement compared to most standard patients who deteriorated. In one of his patients, Allison Carr, the therapy appears to have reversed the paralyzing autoimmune disease in its tracks.

For one disease at least, sickle cell anemia, stem-cell therapy has moved beyond clinical trials. A 2018 review paper refers to the use of adult stem cells for sickle cell disease (which afflicts 100,000 Americans with severe anemia, pain, strokes and organ failure) as the only curative approach for this disease.

Money Down the Drain

One of the biggest hurdles to moving adult stem-cell research forward is funding. There are reports that patients in Burts trials were paying as much as $100,000 to enroll in the trial. Carr had set up a GoFundMe page.

Prentice thinks that the money still being directed by the National Institutes of Health toward embryo funding could go a long way in moving gold standard stem-cell research into the mainstream. Notwithstanding President Donald Trumps recent appointment of a committee to investigate alternatives to fetal tissue and embryonic stem-cell research, these ethically prohibited methods have so far not produced any changes.

Its really disappointing, said Prentice, pointing to the 2018 NIH funding portfolio, which allots $246 million in federal funds to human embryonic research, about the same as it was under the Obama administration.

Thats about a quarter of a billion dollars for just one year. What could that do if it was redirected to actually treat patients or to get them into clinical trials for actual clinical research? Embryonic stem-cell research is not funding a single clinical trial.

Instead, he said, most of that research will be used to inject the human cells into animals, and much of it will be trying to overcome the biggest bugbear that embryonic stem cells have, which is their tendency to grow into tumors.

The job description of the embryonic stem cell at that point in their life is to grow very rapidly and to be able to form basically all of the cells in the human body, said Prentice. This magical so-called pluripotency is also why they grow cancerous.

In fact, Prentice added, researchers test if they are working with true pluripotent stem cells by first injecting them in mice to see if they generate tumors.

This tumorigenicity has so far been an insurmountable technical challenge of embryo cells. The use of these cells pose ethical problems since they require the killing of living human embryos usually leftovers thawed from the freezers of in vitro fertilization businesses.

Ironically, it is the same problem that researchers ran into doing fetal-tissue transplants. Once the shining star of medical promise, federally funded transplants of tissue from aborted babies into patients entranced some medical researchers for nearly 15 years, but ended disastrously.

Prentice thinks NIHs executive director, Francis Collins, a holdover from the Obama administration, is at least part of the reason for the fixation on embryos as well. Ive met with him. He has a very utilitarian ethics, he said.

From a utilitarian perspective, however, embryo research still doesnt add up.

Quit wasting money, said Prentice, and quit wasting lives: the lives of human embryos and the lives of patients we could be curing.

Register correspondent Celeste McGovern writes from Nova Scotia, Canada.

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Embryonic Stem-Cell Research Reaches Moral, Medical Dead End

Embryonic Stem Cell: Definition, Uses and Collection …

Embryonic Stem Cell Definition

An embryonic stem cell is a cell derived from the early stages of an embryo which is capable of differentiating into any type of body cell. Embryonic stem cells are capable of differentiating into any cell type because in the embryo that is what they are used for. As the embryo grows and divides, cells which are generalized must become more and more specific as they divide. This eventually creates the different organs, tissues, and systems of an organism.

After the sperm reaches an egg (oocyte), fertilization occurs and the DNA from the two cells merge into a single nucleus, in a single cell. This is the zygote, and is technically an embryonic stem cell because as it divides it will differentiate into all of the cells of the body. This cell, and the first few divisions of this cell, are totipotent. This means that they have the ability to become an entire organism. Identical twins, for example, develop from the same zygote which accidentally separates when it begins to divide.

In medicine and research, scientist use pluripotent embryonic stem cells. These cells do not have the ability to become an entire organism. Rather, they are directed by signals from the early embryo which tell them which cell type to differentiate into. Scientists prefer these cells for many reasons. First, they can be stored and maintained more easily. Totipotent cells have a tendency to differentiate quickly, and immediately try to become an organism. Pluripotent cells are waiting for a signal to divide, and can be maintained for longer periods. Further, because pluripotent cells are simply waiting for the proper signals to tell them which cell type to become, they can easily be integrated into medical applications in which new tissue must be grown.

There are also other types of stem cells, not to be confused with an embryonic stem cell. Embryonic stem cells are derived from embryos. There are also adult stem cells, umbilical cord stem cells, and fetal stem cells. Not only are these stem cells sometimes more ethically challenging, they are only multipotent, meaning they can only become a small range of cell types.

The use of embryonic stem cells is a very new form of medicine. For decades, the cause of many degenerative diseases and physical injuries has been understood. Tissue damage is the root cause of many of these ailments, and scientist have long been searching for a method of growing tissues which do not easily repair themselves. Because an embryonic stem cell is pluripotent, and can become almost any cell in the body, these cells have long been studied for their possible use in medicine.

Since the late 1950s scientists have been trying to test various methods of growing tissue with an embryonic stem cell. The first clinical trials were in the late 1960s, but not much progress has been made. President Bush put a moratorium on using Federal funds for stem cell research, which was finally lifted by the Obama Administration in 2009. European countries have also faced an uphill battle in funding stem cell research. However, with advances in the science came new discoveries which allowed for more ethical harvesting of an embryonic stem cell. The first treatments with medicinal stem cells were in 2010.

Medically, the embryonic stem cell is limited in its current uses, though many novel applications are in the works. Current treatments focus on the replacement of damaged tissue from injury or disease. Of these, the first treatment approved by the FDA to undergo trials was replacing damaged tissue in spinal injuries. Because nerve cells rarely regenerate, an embryonic stem cell can be used to replace the damage nerve and restore function. In someone with a spinal injury, this means being able to walk again. For a blind person, this might mean being able to see again. While the treatment is still new and success is limited, it has shown some positive results.

Still other medical advances are made with the embryonic stem cell, although these dont come as direct medical treatments but rather as the knowledge that stem cells give us. As an embryonic stem cell differentiates into its target tissue, scientists can study the chemicals and methods it uses to do so. Scientists can also alter the genome of these cells, and study the effects different mutations have on a cells functioning. Between these two paths of discovery, scientists have assembled much information about how and why cells differentiate and divide. Using these tools, scientists are closing in on methods which would allow them to turn regular cell back into a pluripotent stem cell. This process could not only fix injuries and ailments, but could potentially reverse aging and prevent death.

On a less dramatic and grand scale, these methods are also being used to cure common diseases, such as diabetes. By learning how embryonic stem cells become pancreas cells and secrete insulin, scientists are learning the methods of converting other tissues to insulin-secreting tissues. This could help cure diabetes, often caused by the destruction of insulin producing cells. If these were replaced with stem cells, or other cells were induced to become pancreas cells, the disease could be cured. Other diseases, like cystic fibrosis, fragile x syndrome, and other genetic disorders are studied in embryonic stem cells. Not only can many cells be created, but they can be differentiated into different cell types. In this way, a scientist can build a picture of the disease from snapshots of each cell type, and understand exactly how the disease is affecting a person.

While there was once a concern that embryonic stem cells were being harvested without consent from unknowing women, the vast majority are now ethically harvested an in vitro fertilization clinics. In these clinics, in order to get a successful pregnancy, many eggs must be fertilized. Only one is implanted, and with the womans consent the rest can be used to harvest embryonic stem cells. To do this, scientists extract some embryonic stem cells from an embryo when it is only a small ball of cells. This can be seen in the image below.

A harvested embryonic stem cell is placed in a petri dish with nutrients and is allowed to divide. Without any signals from the embryo, the cells remain pluripotent. They continue dividing, fill one dish, and they are transferred to many more dishes and continue to grow. After 6 months of this, they are considered a successful pluripotent embryonic stem cell line. They can then be used to study disease, be used in treatments, or be manipulated genetically to provide models for how cells work.

To test that these cells are indeed pluripotent stem cells, they are injected into mice with depressed immune systems. The mice must have depressed immune systems, or their bodies would naturally reject the human tissue. Once implanted into the mouse, successful pluripotent cells will form a small tumor called a teratoma. This small tumor has different tissue types, and proves that the cell line is still pluripotent and can differentiate into different cell types.

There are a number of other types of stem cells, besides embryonic stem cells. These cells come from different sources and can be used for different purposes. Often, they are only multipotent, and can transform into only a narrow range of cell types. One example is umbilical cord blood stem cells, which have been used in medical treatments to treat various blood diseases and suppressed immune systems. The stem cells in the blood of the umbilical cord can differentiate into almost any type of blood or immune cell, making them multipotent. However, this limits their use in other areas of medicine.

There are also adult stem cells, which survive in various organs throughout the body. These cells are also multipotent, and can only differentiate into the kinds of tissue in which they are found. A common use of adult stem cells is the bone marrow transplant. In this procedure a healthy donor must have their marrow extracted from their bones. The marrow is a blood-like substance on the inside of large bones which creates blood cells and immune cells. Cancer patients, having undergone radiation and chemotherapy, lose most of their immune cells and become immunocompromised. Often a bone marrow transplant is needed to replace these tissues. The new stem cells begin producing new immune cells, which help the patient recover and fight off infection and disease.

1. What is the difference between pluripotent and multipotent stem cells? A. There is no difference B. Pluripotent cells can become a wider variety of cell types C. Multipotent cells can become a wider variety of cell types

Answer to Question #1

B is correct. Pluripotent embryonic stem cells are one step below totipotent stem cells. These pluripotent cells can become almost any cell type in the body, except the cells needed to support a developing embryo. Multipotent cells are already differentiated to a specific degree, and are restricted to creating only a few types of cells.

2. At a certain stage, embryonic stem cells are totipotent. Why dont scientists use these stem cells? A. These cells have the potential to become an entire organism B. The pluripotent stem cells can become more cell types C. Totipotent cells cannot survive in the lab

Answer to Question #2

A is correct. Because totipotent cells have the potential to become an entire organism, they will actively work to do so. That means that whether they are in the lab or in the womb, they will try to direct the development of an organism. They do this by releasing hormones and chemicals which cause the cells to divide and differentiate. Pluripotent cells can be suspended in a generalized state, which makes them better candidates for study and medical procedures.

3. Which of the following ailments cannot potentially be treated with stem cells? A. Brain injury B. Diabetes C. Cancer

Answer to Question #3

C is correct. While the side-effects from treating cancer are treated with stem cells (see above on bone marrow transplants), treating the actual cancer is done with radiation and chemotherapy. These treatments also kill the rapidly dividing stem cells in a persons body, which is why they must be replaced.

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Embryonic Stem Cell: Definition, Uses and Collection ...

Advantages of Embryonic Stem Cell Research | Sciencing

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Advances in stem cell research offer hope to patients suffering from diseases and life-threatening ailments with no known cure. The special regenerative properties of embryonic stem cells give them the power to repair and replenish cells in the body. Scientists are studying how stem cell therapy could be used to restore functioning in damaged cells, tissues and organ systems.

Most cells in the human body are immutable and highly specialized. By contrast, all embryonic stem cells have the extraordinary ability to differentiate into any of the hundreds of specialized cells that comprise the human body. Harvested stem cells continue dividing in the lab for an extended period of time, providing an ongoing supply for research purposes. A small stem cell population can proliferate into millions of cells within months, according to the National Institutes of Health.

Three to five days after conception, a blastocyst forms. Under the right conditions, embryonic stem cells in the blastocyst have the capacity to become brain cells, nerve cells, skin cells, blood cells and more. Researchers use embryos from fertility clinics given by donors for research purposes.

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Adults possess a small number of stem cells in certain tissues, which can repair specific types of cells. For instance, adult hematopoietic stem cells in bone marrow regenerate blood cells; but, hematopoietic cells cant make new nerve cells. Scientists are studying the possibility of manipulating adult stem cells in the lab to make them more versatile.

An advantage of embryonic stem cells is that they are in better condition than adult stem cells. Somatic and stem cells in adults may have mutations from repeated division and exposure to environmental pollutants.

The International Society for Stem Cell Research (ISSCR) suggests that stem cell therapies could help with treating many diseases and injuries. The ISSCR notes that thousands of children diagnosed with leukemia have been helped by blood stem cell treatments. Stems cells are also being used successfully for tissue grafts.

Stem cell research leads to safer and more effective stem cell therapies. A deeper understanding of how embryonic stem cells respond to different conditions could advance the study and treatment of birth defects, for example. The Mayo Clinic supports continued stem cell research because of the many advantageous ways that clinical trials further the medical field. Potential benefits include:

Stem cell therapy helps the body heal itself. Most cells in the human body have a very specific job to do within a particular organ. If cells die or malfunction, the body is capable of replenishing lost cells. Illness, organ failure and death can occur if the number of diseased and dying cells surpasses production of new cells.

Normal cells replicate many times over. Scientists are refining techniques that can jump-start healthy cell production. For example, implanting normal pancreatic cells into a patient with diabetes could restore the ability to produce insulin as the cells multiply.

Embryonic stem cells are pluripotent, meaning they are more versatile in research studies than adult stem cells. The potential benefits of embryo research include discovering new ways of treating diseases, injuries and organ failure. Embryonic stem cells can be manipulated in the lab to develop into any type of cell in the body. Embryo research helps scientists understand how to prevent injected stem cells from growing abnormally and causing tumors.

The use of human embryos for stem cell research has been vigorously discussed and emotionally debated. Destroying human embryos is a commonly raised concern, often based on religious beliefs. The Genetic Science Learning Center notes that embryonic stem cell research poses both moral and ethical questions, such as:

Opponents of embryonic stem cell research argue that embryos have rights because they hold the capacity to develop into a human being. However, the Hastings Center points out that 75 to 80 percent of embryos do not implant in the uterus and that many embryos from fertility clinics are poor quality and not capable of developing into a fetus. Also, donated embryos were scheduled for destruction before the donation was made.

Human embryonic stem (hES) cells are vital to stem cell research because, as previously mentioned, hES cells are pluripotent, unlike other cells in the body. However, scientists are learning how to create induced pluripotent stem (iPS) cells from adult stem cells. Moreover, progress is being made in how to use a patients own stem cells to treat diseases. Alternatives to hES cells may reduce use of human embryonic stem cells.

Perinatal stem cells are another option. Perinatal stem cells have been discovered in umbilical cord blood and in amniotic fluid drawn during an amniocentesis procedure. More research is needed to determine how perinatal stem cells could be used in experimental studies and treatment.

According to the American Association of Neurological Surgeons, the pros of stem cell research include helping millions of people who suffer from debilitating conditions. For instance, stem cell therapies could potentially increase dopamine in the brains of those afflicted with Parkinsons disease. Stem cell research could also help restore functioning for patients with diabetes, heart disease, stroke, cancer, spinal cord injuries, osteoarthritis, Alzheimer's and degenerative diseases like amyotrophic lateral sclerosis (ALS).

The U.S. Food and Drug Administration urges caution before participating in stem cell clinical studies or treatments not approved by the FDA. Claims that stem cell therapies offer a miracle cure are overstated, according to the FDA. Several adverse reactions are possible from emerging therapies that are relatively untested. For instance, in 2016 the FDA was informed of a patient who went blind after receiving an injection of stem cells for an eye condition.

Other FDA examples include:

Societal opinions on ethical issues related to rapidly advancing technologies like cloning and stem cell research influence public policy and government regulations. Former presidents of the U.S. have taken a political stance on the issue and changed regulations to align with the position of their political party. As of 2019, federal funding is available to fund embryonic stem cell research using new lines of cells. Previously, federal funding was limited to studies using a small number of existing embryonic cell lines.

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Advantages of Embryonic Stem Cell Research | Sciencing

Practical Problems with Embryonic Stem Cells – usccb.org

While some researchers still claim that embryonic stem cells (ESCs) offer the best hope for treating many debilitating diseases, there is now a great deal of evidence contrary to that theory. Use of stem cells obtained by destroying human embryos is not only unethical but presents many practical obstacles as well.

"Major roadblocks remain before human embryonic stem cells could be transplanted into humans to cure diseases or replace injured body parts, a research pioneer said Thursday night. University of Wisconsin scientist James Thomson said obstacles include learning how to grow the cells into all types of organs and tissue and then making sure cancer and other defects are not introduced during the transplantation. 'I don't want to sound too pessimistic because this is all doable, but it's going to be very hard,' Thomson told the Wisconsin Newspaper Association's annual convention at the Kalahari Resort in this Wisconsin Dells town. 'Ultimately, those transplation therapies should work but it's likely to take a long time.'....Thomson cautioned such breakthroughs are likely decades away."

-Associated Press reporter Ryan J. Foley "Stem cell pioneer warns of roadblocks before cures," San Jose Mercury News Online, posted on Feb. 8, 2007, http://www.mercurynews.com/mld/mercurynews/16656570.htm

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"Although embryonic stem cells have the broadest differentiation potential, their use for cellular therapeutics is excluded for several reasons: the uncontrollable development of teratomas in a syngeneic transplantation model, imprinting-related developmental abnormalities, and ethical issues."

-Gesine Kgler et al., "A New Human Somatic Stem Cell from Placental Cord Blood with Intrinsic Pluripotent Differentiation Potential," Journal of Experimental Medicine, Vol. 200, No. 2 (July 19, 2004), p. 123.

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From a major foundation promoting research in pancreatic islet cells and other avenues for curing juvenile diabetes:

"Is the use of embryonic stem cells close to being used to provide a supply of islet cells for transplantation into humans?

"No. The field of embryonic stem cells faces enormous hurtles to overcome before these cells can be used in humans. The two key challenges to overcome are making the stem cells differentiate into specific viable cells consistently, and controlling against unchecked cell division once transplanted. Solid data of stable, functioning islet cells from embryonic stems cells in animals has not been seen."

-"Q & A," Autoimmune Disease Research Foundation, http://www.cureautoimmunity.org/Q%20&%20A.htm, accessed July 2004.

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"'I think the chance of doing repairs to Alzheimer's brains by putting in stem cells is small,' said stem cell researcher Michael Shelanski, co-director of the Taub Institute for Research on Alzheimer's Disease and the Aging Brain at the Columbia University Medical Center in New York, echoing many other experts. 'I personally think we're going to get other therapies for Alzheimer's a lot sooner.'...

"[G]iven the lack of any serious suggestion that stem cells themselves have practical potential to treat Alzheimer's, the Reagan-inspired tidal wave of enthusiasm stands as an example of how easily a modest line of scientific inquiry can grow in the public mind to mythological proportions.

"It is a distortion that some admit is not being aggressively corrected by scientists.

"'To start with, people need a fairy tale,' said Ronald D.G. McKay, a stem cell researcher at the National Institute of Neurological Disorders and Stroke. 'Maybe that's unfair, but they need a story line that's relatively simple to understand.'"

-Rick Weiss, "Stem Cells an Unlikely Therapy for Alzheimer's," Washington Post, June 10, 2004, p. A3.

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"ES [embryonic stem] cells and their derivatives carry the same likelihood of immune rejection as a transplanted organ because, like all cells, they carry the surface proteins, or antigens, by which the immune system recognizes invaders. Hundreds of combinations of different types of antigens are possible, meaning that hundreds of thousands of ES cell lines might be needed to establish a bank of cells with immune matches for most potential patients. Creating that many lines could require millions of discarded embryos from IVF clinics."

-R. Lanza and N. Rosenthal, "The Stem Cell Challenge," Scientific American, June 2004, pp. 92-99 at p. 94. [Editor's note: A recent study found that only 11,000 frozen embryos are available for research use from all the fertility clinics in the U.S., and that destroying all these embryos for their stem cells might produce a total of 275 cell lines. See Fertility and Sterility, May 2003, pp. 1063-9 at p. 1068.]

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"Embryonic stem cells have too many limitations, including immune rejection and the potential to form tumors, to ever achieve acceptance in our lifetime. By that time, umbilical cord blood stem cells will have been shown to be a true 'gift from the gods.'"

-Dr. Roger Markwald, Professor and Chair of Cell Biology and Anatomy at the Medical University of South Carolina, quoted in "CureSource Issues Statement on Umbilical Cord Blood Stem Cells vs. Embryonic Stem Cells," BusinessWire, May 12, 2004, also at http://curesource.net/why.html.

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"'We're not against stem-cell research of any kind,' said [Tulane University research professor Brian] Butcher. 'But we think there are advantages to using adult stem cells. For example, with embryonic stem cells, a significant number become cancer cells, so the cure could be worse than the disease. And they can be very difficult to grow, while adult stem cells are easy to grow.'"

-Heather Heilman, "Great Transformations," The Tulanian (Spring 2004 issue), at http://www2.tulane.edu/article_news_details.cfm?ArticleID=5155.

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"There are still many hurdles to clear before embryonic stem cells can be used therapeutically. For example, because undifferentiated embryonic stem cells can form tumors after transplantation in histocompatible animals, it is important to determine an appropriate state of differentiation before transplantation. Differentiation protocols for many cell types have yet to be established. Targeting the differentiated cells to the appropriate organ and the appropriate part of the organ is also a challenge."

-E. Phimister and J. Drazen, "Two Fillips for Human Embryonic Stem Cells," New England Journal of Medicine, Vol. 350 (March 25, 2004), pp. 1351-2 at 1351.

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Harvard researchers, trying to create human embryonic stem cell lines that are more clinically useful than those now available, find that their new cell lines are already genetically abnormal:

"After prolonged culture, we observed karyotypic changes involving trisomy of chromosome 12..., as well as other changes... These karyotypic abnormalities are accompanied by a proliferative advantage and a noticeable shortening in the population doubling time. Chromosomal abnormalities are commonplace in human embryonal carcinoma cell lines and in mouse embryonic stem-cell lines and have recently been reported in human embryonic stem-cell lines."

-C. Cowan et al., "Derivation of Embryonic Stem-Cell Lines from Human Blastocysts," New England Journal of Medicine, Vol. 350 (March 25, 2004), pp. 1353-6 at 1355.

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"[Johns Hopkins University] biologist Michael Shamblott said...major scientific hurdles await anybody wishing to offer a treatment, let alone a cure, based on cells culled from embryos.

"Among the major obstacles is the difficulty of getting embryonic stem cells master cells that generate every tissue in the human body to become exactly the type of cell one wants... Scientists...haven't been able to guarantee purity cells, for instance, that are destined to become muscle cells and nothing else...

"Transplanting a mixed population of cells could cause the growth of unwanted tissues. The worst case could see stem cells morphing into teratomas, particularly gruesome tumors that can contain hair, teeth and other body parts.

"Another issue is timing... Stem cells pass through many intermediate stages before they become intermediate cells such as motor neurons or pancreatic or heart cells. Deciding when to transplant remains an open question, and the answer might differ from disease to disease.

"...In tackling Lou Gehrig's disease, [Johns Hopkins neurologist Dr. Jeffrey] Rothstein figured that cells that haven't committed themselves to becoming motor neurons would stand the best chance, once implanted, of reaching out and connecting with the cells that surround them. What he found, however, is that these immature cells didn't develop much once transplanted into lab animals."

-Jonathan Bor, "Stem Cells: A long road ahead," Baltimore Sun, March 8, 2004, p. 12A.

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"Tony Blau, a stem-cell researcher at the University of Washington, said it is 'extremely laborious' to keep embryonic cells growing, well-nourished and stable in the lab so they don't die or turn into a cell type with less potential. Researchers need to know how to channel the stem cells to create a specific kind of cell, how to test whether they're pure, and how to develop drugs that could serve as a sort of antidote in case infused stem cells started creating something dangerous, such as cancer.

"Big companies, Blau said, want to know that their drugs will be almost completely stable, standard, pure and consistent, because they can behave differently if they aren't. Stem cells never will achieve that kind of standardization, Blau said, because living cells are more complex than chemically synthesized drugs."

-Luke Timmerman, "Stem-cell research still an embryonic business," Seattle Times, Business & Technology section, February 22, 2004, at http://seattletimes.nwsource.com/html/businesstechnology/2001862747_stemcells22.html.

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"[W]ithin the ESC research community, realism has overtaken early euphoria as scientists realize the difficulty of harnessing ESCs safely and effectively for clinical applications. After earlier papers in 2000 and 2001 identified some possibilities, research continued to highlight the tasks that lie ahead in steering cell differentiation and avoiding side effects, such as immune rejection and tumorigenesis."

-Philip Hunter, "Differentiating Hope from Embryonic Stem Cells," The Scientist, Vol. 17, Issue 34 (December 15, 2003), at http://www.the-scientist.com/yr2003/dec/hot_031215.html.

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"Long-term culture of mouse ES [embryonic stem] cells can lead to a decrease in pluripotency and the gain of distinct chromosomal abnormalities. Here we show that similar chromosomal changes, which resemble those observed in hEC [human embryonal carcinoma] cells from testicular cancer, can occur in hES [human embryonic stem] cells.... The occurrence and potential detrimental effects of such karyotopic changes will need to be considered in the development of hES cell-based transplantation therapies."

-J. Draper et al., "Recurrent gain of chromosomes 17q and 12 in cultured human embryonic stem cells," Nature Biotechnology, Vol. 22 (2003), pp. 53-4.

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"James A. Thompson of the University of Wisconsin, Madison, and his colleagues managed to isolate and culture the first human embryonic stem cells in 1997. Five years later, big scientific questions remain. [Harvard embryonic stem cell researcher Doug] Melton and his colleagues, for instance, don't yet know how to instruct the totipotent stem cells to become the specific cells missing in a diabetic person, the pancreatic beta cell.

"'Normally, if you take an embryonic stem cell, it will make all kinds of things, sort of willy-nilly,' says Melton."

-J. Mitchell, "Stem Cells 101," PBS Scientific American Frontiers, May 28, 2002, http://www.pbs.org/saf/1209/features/stemcell.htm.

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"Unlike stem cells isolated from the embryo, [adult stem cells] do not carry the same risks of cancer or uncontrollable growth after transplant, and they can be isolated from patients requiring treatment, thus avoiding all problems of immune rejection and the need for immune suppressive drugs that carry their own risks.

"...Embryonic stem cells are promoted on grounds that they are developmentally more flexible than adult stem cells. But too much flexibility may not be desirable. Transplant of embryonic cells into the brains of Parkinson's patients turned into an irredeemable nightmare because the cells grew uncontrollably. Embryonic stem cells also show genetic instability and carry considerable risks of cancer... When injected under the skin of certain mice, they grow into teratomas, tumors consisting of a jumble of tissue types, from gut to skin to teeth, and the same happens when injected into the brain."

-Dr. Mae-Wan Ho and Prof. Joe Cummins on behalf of the Institute of Science in Society (ISIS), "Hushing Up Adult Stem Cells," ISIS report, February 11, 2002, at http://www.i-sis.org.uk/HUASC.php.

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"'I even hear from patients whose fathers have lung cancer,' said Dr. Hogan, a professor at Vanderbilt School of Medicine. 'They have a whole slew of problems they think can be treated. They think stem cells are going to cure their loved ones of everything.'

"If it ever happens, it will not happen soon, scientists say. In fact, although they worked with mouse embryonic stem cells for 20 years and made some progress, researchers have not used these cells to cure a single mouse of a disease...

"Scientists say the theory behind stem cells is correct: the cells, in principle, can become any specialized cell of the body. But between theory and therapy lie a host of research obstacles...the obstacles are so serious that scientists say they foresee years, if not decades, of concerted work on basic science before they can even think of trying to treat a patient."

-Gina Kolata, "A Thick Line Between Theory and Therapy, as Shown with Mice," New York Times, December 18, 2001, p. F3.

***

"Mice cloned from embryonic stem cells may look identical, but many of them actually differ from one another by harboring unique genetic abnormalities, scientists have learned...

"The work also shows for the first time that embryonic stem cells...are surprisingly genetically unstable, at least in mice. If the same is true for human embryonic stem cells, researchers said, then scientists may face unexpected challenges as they try to turn the controversial cells into treatments for various degenerative conditions."

-Rick Weiss, "Clone Study Casts Doubt on Stem Cells," Washington Post, July 6, 2001, p. A1.

***

"ES cells have plenty of limitations... For one, murine ES cells have a disturbing ability to form tumors, and researchers aren't yet sure how to counteract that. And so far reports of pure cell populations derived from either human or mouse ES cells are few and far between fewer than those from adult stem cells."

-Gretchen Vogel, "Can Adult Stem Cells Suffice?", Science, Vol. 292 (June 8, 2001), pp. 1820-1822 at 1822.

***

"Rarely have specific growth factors or culture conditions led to establishment of cultures containing a single cell type.... [T]he possibility arises that transplantation of differentiated human ES cell derivatives into human recipients may result in the formation of ES cell-derived tumors... Irrespective of the persistence of stem cells, the possibility for malignant transformation of the derivatives will also need to be addressed."

-J. S. Odorico et al, "Multilineage differentiation from human embryonic stem cell lines," Stem Cells Vol. 19 (2001), pp. 193-204 at 198 and 200, at http://stemcells.alphamedpress.org/cgi/reprint/19/3/193.pdf.

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Practical Problems with Embryonic Stem Cells - usccb.org

Obama Ends Stem Cell Research Ban – CBS News

March 9, 2009 / 8:10 AM / CBS/AP

Fulfilling a campaign promise, Mr. Obama signed an executive order expected to set in motion increased research that supporters believe could uncover cures for serious ailments from diabetes to paralysis.

Mr. Obama's action, before a packed East Room audience, reverses former President George W. Bush's policy on stem cell research by undoing a 2001 directive that banned federal funding for research into stem lines created after that date.

Mr. Bush limited the use of taxpayer money to only the 21 stem cell lines that had been produced before his decision. He argued he was defending human life because days-old embryos - although typically from fertility clinics and already destined for destruction - are destroyed to create the stem cell lines.

The Obama order reverses that without addressing a separate legislative ban, which precludes any federal money paying for the development of stem cell lines. The legislation, however, does not prevent funds for research on those lines created without federal funding. (Read more about what this Executive Order will do -- and won't do.)

Researchers say the newer lines created with private money during the period of the Bush ban are healthier and better suited to creating treatment for diseases. Embryonic stem cells are master cells that can morph into any cell of the body. Scientists hope to harness them so they can create replacement tissues to treat a variety of diseases - such as new insulin-producing cells for diabetics, cells that could help those with Parkinson's disease or maybe even Alzheimer's, or new nerve connections to restore movement after spinal injury.

Mr. Obama called his decision a "difficult and delicate balance," an understatement of the intense emotions generated on both sides of the long, contentious debate. He said he came down on the side of the "majority of Americans" who support increased federal funding for the research, both because strict oversight would prevent problems and because of the great and lifesaving potential it holds.

CBS News polling on the topic shows that Americans do support medical research using embryonic stem cells. In 2007, the last time CBS News asked the question, sixty-five percent said they approved compared to twenty-five percent who disapproved. The number of those who approved had gone up steadily since the 2004 when fifty percent approved. (Read more about the polling.)

"Rather than furthering discovery, our government has forced what I believe is a false choice between sound science and moral values," Mr. Obama said. "In this case, I believe the two are not inconsistent. As a person of faith, I believe we are called to care for each other and work to ease human suffering. I believe we have been given the capacity and will to pursue this research and the humanity and conscience to do so responsibly." (Read all of Mr. Obama's remarks.)

Mr. Obama warned against overstating the eventual benefits of the research. But he said his administration "will vigorously support scientists who pursue this research," taking a slap at his predecessor in the process.

"I cannot guarantee that we will find the treatments and cures we seek. No president can promise that. But I can promise that we will seek them actively, responsibly, and with the urgency required to make up for lost ground."

It's a matter of competitive advantage globally as well, the president argued.

"When government fails to make these investments, opportunities are missed. Promising avenues go unexplored. Some of our best scientists leave for other countries that will sponsor their work. And those countries may surge ahead of ours in the advances that transform our lives," Mr. Obama said.

Early Show medical contributor Dr. Holly Phillips pointed out that such research was never banned or illegal. "The question that we're addressing today is what role, if any, federal funding should have" in this research.

"Many scientists for the last eight years have been complaining that they're spending more time trying to find funding for their research than actually doing their research. So for them this will really have a profound effect," Phillips said. "Certainly on an international level in medicine we're so excited about this research and the potential for healing that it has. So I think less red tape will have a profound effect."

Of the diseases or conditions that may be most affected by the end of the federal ban, Phillips said, "People are most excited about the neurological illnesses, things like Parkinson's and Alzheimer's. A group in California will start using embryonic stem cells in humans to hopefully cure spinal cell injuries for people who have been paralyzed from the waist down. We're also seeing some hope in treating diabetes, heart disease and even strokes. So really, millions of people could be affected by this research."

"We've got eight years of science to make up for," said Dr. Curt Civin, whose research allowed scientists to isolate stem cells and who now serves as the founding director of the University of Maryland School of Medicine's Center for Stem Cell Biology and Regenerative Medicine. "Now the silly restrictions are lifted."

Mr. Bush and his supporters said they were defending human life; days-old embryos - typically from fertility-clinic leftovers otherwise destined to be thrown away - are destroyed for the stem cells.

Family Research Council, which advocates for a "Judeo-Christian worldview" and warns against the reproductive cloning of a human being, opposes the use of embryonic stem cells, promoting instead adult stem cells as being superior.

Of Mr. Obama's new order, FRC's Dr. David Prentice told CBS' The Early Show, "In terms of scientific advances I don't think we are going to see anything for this. This is more of an ideological move."

House Republican Leader John Boehner said the president's repeal of the ban, "runs counter to President Obama's promise to be a president for all Americans. For a third time in his young presidency, the president has rolled back important protections for innocent life, further dividing our nation at a time when we need greater unity to tackle the challenges before us." (Read more about Republican reaction to the move.)

The president was insistent that his order would not open the door to human cloning.

"We will develop strict guidelines, which we will rigorously enforce, because we cannot ever tolerate misuse or abuse," Mr. Obama said. "And we will ensure that our government never opens the door to the use of cloning for human reproduction. It is dangerous, profoundly wrong, and has no place in our society, or any society."

Mr. Obama also issued a memo promising to restore "scientific integrity to government decision-making." That policy change was aimed more broadly than the stem cell debate, to reach into areas such as climate change as well.

"Promoting science isn't just about providing resources it is also about protecting free and open inquiry," Mr. Obama said. "It is about letting scientists like those here today do their jobs, free from manipulation or coercion, and listening to what they tell us, even when it's inconvenient especially when it's inconvenient. It is about ensuring that scientific data is never distorted or concealed to serve a political agenda and that we make scientific decisions based on facts, not ideology.

Mr. Obama said the presidential memorandum was the beginning of a process that would ensure that his administration: bases its decision "on the soundest science," appoints scientific advisers based on their credentials and experience, not their politics or ideology, and is "open and honest" about the science behind its decisions.

"We view what happened with stem cell research in the last administration is one manifestation of failure to think carefully about how federal support of science and the use of scientific advice occurs," said Harold Varmus, chairman of the White House's Council of Advisers on Science and Technology.

First published on March 9, 2009 / 8:10 AM

2009 CBS Interactive Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.

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Obama Ends Stem Cell Research Ban - CBS News

Types of Stem Cells A Closer Look at Stem Cells

Tissue-specific stem cells

Tissue-specific stem cells (also referred to assomaticoradultstem cells) are more specialized than embryonic stem cells. Typically, these stem cells can generate different cell types for the specific tissue or organ in which they live.

For example, blood-forming (orhematopoietic) stem cells in the bone marrow can give rise to red blood cells, white blood cells and platelets. However, blood-forming stem cells dont generate liver or lung or brain cells, and stem cells in other tissues and organs dont generate red or white blood cells or platelets.

Some tissues and organs within your body contain small caches of tissue-specific stem cells whose job it is to replace cells from that tissue that are lost in normal day-to-day living or in injury, such as those in your skin, blood, and the lining of your gut.

Tissue-specific stem cells can be difficult to find in the human body, and they dont seem to self-renew in culture as easily as embryonic stem cells do. However, study of these cells has increased our general knowledge about normal development, what changes in aging, and what happens with injury and disease.

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Types of Stem Cells A Closer Look at Stem Cells

Embryonic Stem Cell Research – rtlofneo.com

Embryonic Stem Cell Research

is taking a five day old living human embryo, cutting him or her open and extracting embryonic stem cells from the inside, thus killing a living human embryo.

Most embryonic stem cells are derived from embryos that develop from eggs that have been fertilizedinvitroin a clinicand then donated for research purposes. To obtain embryonic stem cells, the early embryo has to be destroyed. This means destroying a human life.A human embryo is a human being in the embryonic stage, just as an infant is a human being in the infant stage.No medical cures have resulted in working with embryonic stem cells.

Adult stem cells (also referred to as non-embryonic stem cells) are present in adults, children, infants, placentas, umbilical cords, and cadavers. Obtaining stem cells from these sources does not result in certain harm to a human being. In contrast to research on embryonic stem cells,adult stem cell research has already resulted in numerous instances of actual clinical benefit to patients.

Another potential obstacle encountered by researchers engaging in embryonic stem cell research is the possibility that embryonic stem cells would not be immunologically compatible with patients and would therefore be rejected, much like a non-compatible kidney would be rejected. A proposed solution to this problem is to create an embryonic clone of a patient and subsequently destroy the clone in order to harvest his or her stem cells. Cloning for this purpose has been termed therapeutic cloningdespite the fact that the subject of the researchthe cloneis not healed but killed. No one should be free to pursue gain (financial, health-related, or otherwise) through immoral or unethical means such as the taking of innocent life. We must not sacrifice one class of human beings (the embryonic) to benefit another (those suffering from serious illness).

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Embryonic Stem Cell Research - rtlofneo.com

The Ethics Of Embryonic Stem Cell Research Viewpoint Essay

Posted at 12.05.2018

Since its breakthrough in 1963, (SC His, 2004) Stem Cell Research has helped the look and developing of cures which had looked like impossible mere generations earlier. Since then, huge progress has been made in finding better and more efficient means of utilizing these stem skin cells, and the huge benefits they offer. However, as with all revolutionary innovations, stem cell research goes on to handle opposition on different fronts, with many thinking it to be something inherently unethical. Such disagreement on the use of individuals embryonic stem cell (hESC) research predicated on religious and honest grounds must turn into a thing of days gone by, since the medicinal cures for diseases and disabilities which range from burns and spinal-cord accidents, to Parkinson's disease and even cancer tumor, make hESC research a miracle therapy that will make current disease something of days gone by.

Stem cells are essentially primitive cells having the ability to become all or almost all of the different types of cells in the body. Stem cells have usually been defined as not fully driven to be any particular type of cell or cells. They could be either "pluripotent" (as is the situation with hESC) where they can become any sort of tissues or "multipotent" (which is what "adult" stem cells are) and have the ability to transform only into certain types of muscle. Stem cells are unique from other cell types because they're simply unspecialized skin cells capable of renewing themselves, sometimes even after long cycles of inactivity, and this 's the reason which makes them so important (Irving).

Scientists been employed by with two kinds of stem skin cells from family pets and humans: embryonic or "pluripotent" stem skin cells and non-embryonic or "adult" stem cells. It really is of significant importance that the leading scientists in the study of mature stem cells present compelling arguments on why we must pursue research on both pluripotent and adult stem cells. Although some stem cells are present in men and women, there might not be a person adult stem cell for every kind of cell in the torso. The main thing to keep in mind is the fact pluripotent and mature stem skin cells also differ in their quality. Pluripotent stem cells have almost miraculous capacity to self-renew and also form numerous cell types, however in contrast the full potential of mature stem cells is uncertain, and a sizable amount of information suggests that they may be more limited. Because of these constraints, it is of extreme importance that research is pursued on both pluripotent and adult stem cells together (Lim).

The features of hESC

There are several different reasons why specific research of real human pluripotent stem skin cells might trigger better treatment, or ideally even cures, of several diseases.

Firstly, pluripotent stem skin cells could help us to understand the complex happenings that occur during normal human development. This research can identify the factors involved in the cellular decision-making process that results in cell field of expertise. For instance why do some skin cells become heart skin cells, while other skin cells become liver cells? A better understanding of the normal functions of skin cells would greatly boost the database of scientific knowledge whose aim would be to find the mistakes in these procedures and finally find ways to repair them (Marshall).

Secondly, and most importantly, real human pluripotent stem cells be capable of generate skin cells and tissue that could be used for "cell transplantation remedies, " These therapies would be targeted at finding ways to cure the diseases and disorders resulting from the dysfunctioning of specific types of cells and muscle. Although donated organs can, and are, sometimes used to replace diseased or destroyed tissue, the pure number of people suffering from the number of the disorders is much larger than the amount of organs or cells available for transplantation. By rousing pluripotent stem skin cells to build up into specialized skin cells and tissue, we have anticipation of finding ways to replace cells and tissue and therefore be able to treat a multitude of diseases, conditions and disabilities. (Van Der Kooy).

Ethical Considerations

Ethics is generally thought as "the rules of conduct accepted in respect to a particular class of individuals actions or a specific group, culture". (Dictionary. com) Ethics, however, cannot be considered as being truly a professional body of knowledge. Ethics is quite simply a conversation about questions. In that dialogue, everyone has a place. Most of us have our own moral intuitions. Relating to embryonic stem cell research, the question that we face is the long standing one of if the end justifies the means? Opponents of hESC research will probably claim that it is wrong to use embryos as a mere methods to our ends somewhat than as ends in themselves. This discussion boasts that since in destroying the embryo we are employing this "life" or "individual" as a means towards various other individual being's end, then it is incorrect to damage this embryo. The simple and understandable response by advocates of hESC research is that the embryo will be destroyed in any case, and the fair move to make is to utilize it to help another individual instead of throwing it away. Why should we avoid the curing of men and women on the basis of religious morality, it is merely not acceptable for the present day times in which we reside in.

A Slippery Slope

The slippery slope objection simply claims that after we start down the road of the creation of life only to eliminate it for other's purposes or benefits, then we won't be able to set restrictions to the risks imposed on our "to life. " It's advocated that since the proponents of hESC research justify early embryo damage and completely overlook the embryo's natural moral status, the end result will be a diminishing of respect for all individuals generally. What follows, because of this objector, is that such justification of the damage of early on embryos will lead to a rationale which could justify harmful tests on other individuals subjects. Although some slippery slope quarrels are valid due to the logical dynamics of the move from one situation to another, the current argument is significantly a far more psychological one when compared to a logical one. It is basically an argument that in taking current activities our thoughts will deteriorate and we will not be able to clearly assess our future decisions which may be wrong. That is an argument which has outlasted its sensible use. Since even the greatest nations on earth have come to understand that hESC research is vital to the continuation of the movement of human being knowledge. The one puzzling factor is the amount of folks who still believe scientific research such as this should be quit based on morality. It is a paradox that must definitely be fixed if we are to progress into an improved tomorrow for population (Lanza, Cibelli).

Future Endeavors

Research on stem skin cells continues to move forward knowledge about the countless unknowns related to the creation of individuals life, and also other organisms. Stem cell research is a remarkable field of research, but much like many expanding domains of scientific study, it increases questions as quickly as it creates new answers. An effective understanding must be produced, signifying the fact that the damage of a given amount of embryos will not alter the continuing future of the whole human race as considerably as some seem to be to predict. The grave evil that we affiliate with the damage of human life-and more broadly with using people as methods to an end- seems to reflects the actual fact that such destruction is either dreadful for the individuals whose lives are damaged or used, unlike their will. Embryos, however, are very different, since their damage does not have any meaning on their behalf or anyone else for example, unless they can be averted from being treated due to ethical restrictions. We must treat embryos in the manner which benefits mankind to its fullest magnitude. This will not entail using them however we see fit, whatever the consequences; but there is absolutely no reasonable reason to forgo the large benefits, and the very helpful discoveries that doctors and scientists expect will follow from intense research on hESCs. There is absolutely no reason why the near future should not commence around.

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The Ethics Of Embryonic Stem Cell Research Viewpoint Essay

Embryonic Stem Cells and Artificial Stem Cells Are …

Artificial stem cells, or induced pluripotent stem cells, were made from embryonic stem cells, and then turned into the neural cells pictured here. These artificial stem cells showed a differentiation potential equal to that of embryonic stem cells. [Jiho Choi, HSCI]

Comparing embryonic stem cells and induced pluripotent stem cells can be a little like comparing apples and oranges. Or to put it another way, apples-to-apples comparisons can be hard to arrange because embryonic stem cells and induced pluripotent stem cells may be genetically distinct. In fact, they usually reflect sex, race, and ancestral differences. So, when embryonic stem cells and induced pluripotent stem cells behave differently, as they often do, there is no telling if variations come down to basic genetic differences, or if variations are due to the rigors of reprogrammingwhich adult cells must endure to achieve artificial or induced pluripotency, but which embryonic stem cells are spared.

Because apples-to-apples comparisons are so hard to come by, stem cell scientists have never been able to agree whether embryonic stem cells and induced pluripotent stem cells are equivalent. Even after performing hundreds of experiments, stem cell scientists remained divided. Some experiments suggested that the two types of stem cells functioned similarly and could be used interchangeably, and other experiments suggested that they were fundamentally different.

To help resolve the controversy, stem cell scientists based at Harvard Medical School contrived an experiment that was as much of an apples-to-apples comparison as they could manage. They tricked human embryonic stem cells (hESCs) into becoming human induced pluripotent stem cells (hiPSCs) by first coaxing hESCs to form skin cells. Then they reprogrammed those skin cells into hiPSCs. Finally, they compared the gene products of the hiPSCs with those of the hESCs.

The results of the comparison would be telling, the scientists reasoned, because the hESCs and the hiPSCs were genetically identical. The comparison, it turned out, indicated that the different types of stem cell could not be distinguished by a consistent gene expression signature and were, in the scientists words, molecularly and functionally equivalent.

Details of the scientists work appeared October 26 in the journal Nature Biotechnology, in an article entitled, A comparison of genetically matched cell lines reveals the equivalence of human iPSCs and ESCs.

Here we use genetically matched hESC and hiPSC lines to assess the contribution of cellular origin (hESC vs. hiPSC), the Sendai virus (SeV) reprogramming method and genetic background to transcriptional and DNA methylation patterns while controlling for cell line clonality and sex, wrote the authors. We find that transcriptional and epigenetic variation originating from genetic background dominates over variation due to cellular origin or SeV infection.

When the scientists examined the gene products from the hESC and hiPSC cells, they found that only about 50 of the 200,000 genes that make up the human genome were expressed differently. Whats more, the differentially expressed genes were transcribed at such low levels that any apparent transcriptional difference between hESC and hiPSC cells may be nothing more than transcriptional noise.

Finally, the researchers assessed the functional properties of their ES and iPS cell lines. The researchers found that the cell lines had equal potentials to differentiate into neural cells and a variety of other specialized cell lineages.

When using these cell lines and assays, and after considering a number of technical and biological variables, we find that ES cells and iPS cells are equivalent, said Konrad Hochedlinger, Ph.D., a principal faculty member at the Harvard Stem Cell Institute and a senior author of the Nature Biotechnology paper. Dr. Hochedlinger added the caveat that not all practical applications can account for the variables, and that the science has not yet advanced to where iPS cells can replace embryonic stem cells in every situation.

Embryonic stem cells are still an important reference point, against which other pluripotent cells are compared, noted Dr. Hochedlinger. Along those lines, this study increases the 'value' of iPS cells.

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Embryonic Stem Cells and Artificial Stem Cells Are ...

Embryonic stem cells | Cells | MCAT | Khan Academy

An overview of early development of a zygote to an embryo. Embryonic and somatic stem cells. Created by Sal Khan.

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Embryonic stem cells | Cells | MCAT | Khan Academy