Archive for the ‘Embryonic Stem Cells’ Category

Embryonic Stem Cell – an overview | ScienceDirect Topics

Embryonic Stem Cells | Posted by admin
May 22 2019

Charles E. Murry, ... Lior Gepstein, in Heart Development and Regeneration, 2010

Embryonic stem cells (ESCs) are pluripotent cells derived from the inner cell mass of blastocyst-stage embryos. Mouse embryonic stem cells (mESCs) have been studied for several decades, and have provided major advances in our understanding of developmental biology and gene function in the adult organism. The single greatest application of mouse embryonic stem cells has been in studies of gene function through homologous recombination (knockout or knockin strategies). These studies were made possible by the remarkable ability of genetically-modified embryonic stem cells to incorporate into all tissues of a developing mouse after injection into a blastocyst, followed by the ability of resulting chimeric mice to pass the genetic modification via the germline. Embryonic stem cells have also been useful tools for understanding molecular events controlling differentiation into the early germ layers and more distal branches of the developmental tree. Over the last 15 years an increasing number of groups have become interested in the use of mouse embryonic stem cells as a cell source to treat murine models of cell deficiency.

Research in this area gained worldwide prominence, extending far beyond the usual scientific community, when Jamie Thomsons group at the University of Wisconsin reported developing the first lines of human embryonic stem cells (hESCs) in 1998 (Thomson et al., 1998b). A veterinary pathologist with an interest in early human development, Thomson had honed his skills by first deriving lines of embryonic stem cells from nonhuman primates (marmosets and rhesus monkeys) (Thomson et al., 1995, 1996). To derive human embryonic stem cells, Thomsons group worked with blastocysts donated by fertility clinic patients, who no longer intended to use these spare embryos for reproductive purposes (these blastocyts are commonly discarded if they are not to be used for reproductive purposes). The embryos were 5 days post-in vitro fertilization, and were at the blastocyst stage, a hollow ball of 150 cells surrounded by a carbohydrate-rich zona pellucida. Blastocysts contain a rim of trophoectoderm cells, which gives rise to the placenta and amniotic membranes, and an inner cell mass, which gives rise to the embryo proper. (By way of comparison, a 5-day-old embryo derived from traditional fertilization is at a preimplantation stage, still residing in the fallopian tube). To derive the human embryonic stem cells, Thomsons group enzymatically digested the zona pellucida and removed the trophoectoderm using antibodies and complement (immunosurgery) (Fig. 1), leaving the inner cell mass intact. The inner cell mass was placed into a culture system, using feeder layers of mouse embryonic fibroblasts to provide a still-unknown set of factors that had maintained other primate embryonic stem cells in the undifferentiated state. The human cells thrived in this environment, growing for hundreds of population doublings while still expressing molecular markers of pluripotency and retaining the ability to differentiate into a wide variety of cell types in vitro. Importantly, after implantation into immuno-tolerant mice, human embryonic stem cells formed teratomas, tumors comprised of cells from endoderm, mesoderm and ectoderm. At present, teratoma formation represents the most definitive evidence for human embryonic stem cell potency, since human blastocyst injection is widely-considered to be unethical. Since this original publication, over 100 lines of human embryonic stem cells have been derived worldwide by similar techniques (Cowan et al., 2004; Musri et al., 2006).

Figure 1. Embryonic stem cell derivation. Cells in the inner cell mass (ICM) of pre-implantation embryos are isolated by the removal of the trophectoderm by immunosurgery (antibody and complement-mediated lysis). To maintain cells in the undifferentiated state, inner cell mass cells are plated on a mouse embryonic fibroblasts feeder layer. These undifferentiated cells can be induced to differentiate into cells from the different germ layers.

It is important to consider the scientific context in which this advancement came. The late-1990s and early-2000s had yielded a number of other major scientific advancements, including sequencing of the human genome (Lander et al., 2001) and cloning of the first mammal, Dolly the sheep (Campbell et al., 1996). Thus, within a few short years, science had delivered the genetic blueprint of humanity, techniques to completely dedifferentiate a cell and grow a new mammal from it, and early human cells that could develop into any tissue. Understandably, this triggered a response that extended beyond the scientific community and into the lay press, public coffeehouses, churches and political forums. Most countries are still debating the extent to which human embryonic stem cell research should be regulated, and public policies range widely, from governmental encouragement, to legal restrictions, to outright bans. While not the topic of this chapter, we would encourage all readers to explore the ethics and policy implications of human embryonic stem cell research, and we refer those interested to references (Green, 2001; Daley et al., 2007; Sugarman, 2007) for in-depth analyses.

Human embryonic stem cells share many similarities with their murine counterparts, but they also have several important differences. Like mouse embryonic stem cells, human embryonic stem cells can divide extensively without telomere shortening and by this criterion appear to be immortal. Although there is not complete overlap with mouse embryonic stem cells, human embryonic stem cells express surface markers characteristic of pluripotent cells. Additionally, both embryonic stem cell types express transcription factors required for pluripotency, including Oct4 and Nanog. In mouse embryonic stem cells, the cytokine leukemia inhibitory factor (LIF) is necessary to maintain cells in their pluripotent state (Williams et al., 1988; Pease and Williams, 1990). In contrast, human embryonic stem cells will differentiate in the presence of LIF (Zaehres et al., 2005) and require FGF for pluripotency. Bone morphogenetic proteins (BMPs) contribute to the maintenance of pluripotency of mouse embryonic stem cells (Ying et al., 2003), whereas they induce trophoblast differentiation in human embryonic stem cells (Xu et al., 2002). The optimal conditions to maintain human embryonic stem cells in the pluripotent state are still being worked out. For this reason, most investigators currently use either mouse embryonic fibroblast feeder layers, or medium conditioned by these cells (supplemented with bFGF) (Xu et al., 2001) for growth and maintenance of undifferentiated human embryonic stem cells.

Mouse embryonic stem cells typically grow as tight clusters and show a high plating efficiency after dissociation to single cells. These characteristics facilitate their low-density plating and subsequent isolation of subclones. In contrast, undifferentiated human embryonic stem cells typically grow as flat two-dimensional colonies, which are passaged by forming smaller clumps (either through partial enzymatic digestion or mechanical dissociation) and allowing them to expand. Furthermore, the establishment of clonal lines is more difficult with human embryonic stem cells, because they do not tolerate single cell dispersion as well as mouse embryonic stem cells. Human embryonic stem cells must be karyotyped regularly to screen for chromosomal abnormalities, such as trisomies 12 and 22, as well as several translocation variants (reviewed in Baker et al., 2007) that can accumulate with time in culture. Time in culture can also affect the differentiation efficiency of some cell types, including cardiomyocytes. It is likely that these difficulties reflect our still-imperfect ability to culture the cells, which may improve as the community gains experience.

The difference between mouse embryonic stem cells and human embryonic stem cells has been assumed to relate to species differences in signaling requirements for pluripotency. Recently, however, two groups isolated pluripotent cells from postimplantation stage mouse epiblasts (Brons et al., 2007; Tesar et al., 2007). These epiSCs do not use the LIF/STAT3 pathway for maintaining pluripotency, but instead use pathways initiated by activin/nodal and FGF, similar to human embryonic stem cells. Interestingly, while epiSCs formed teratomas after injection into host mice, they did not generate chimeric embryos after blastocyst injection. The similarity of mouse epiSCs to human embryonic stem cells has raised the possibility that signaling pathways between species are actually conserved, with the difference being that human embryonic stem cells represent a later developmental stage than mouse embryonic stem cells.

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Embryonic Stem Cell - an overview | ScienceDirect Topics

Embryonic Stem Cell Research and Vaccines using Fetal Tissue

Embryonic Stem Cells | Posted by admin
May 06 2019

To defend his recent decision on stem cell research, President Bush has compared it to the moral judgment that it may be acceptable to use a vaccine cultured in fetal tissue that ultimately came from induced abortions. The President's analogy is invalid because it blurs together two very different questions arising from the use of fetal tissue in medical research:

Should a government agency or private company use tissue from induced abortions for vaccine development or other research? The Catholic bishops have answered in the negative. Such use tends to legitimize abortion as a source of "life-affirming" treatments, and requires collaboration with the abortion industry, which should be avoided. This judgment is reflected in policies governing Catholic health care. See Ethical and Religious Directives for Catholic Health Care Services (4th edition, 2001): "Catholic health care institutions need to be concerned about the danger of scandal in any association with abortion providers" (Directive 45), and "Catholic health care institutions should not make use of human tissue obtained by direct abortions even for research and therapeutic purposes" (Directive 66).

If such collaboration with abortion has already taken place, and the only vaccine made available for serious diseases contains material that was cultured in fetal tissue from an abortion, may Catholics -- out of concern for their own health or that of their children or the community submit to this vaccine without committing serious sin? Most Catholic moralists have replied in the affirmative. The recipient of the vaccine took no part in decisions to base the vaccine on this morally unacceptable source, but is coping with the results of immoral decisions made by others.

It is invalid to cite moral opinions about question (2) to avoid the moral problem posed by question (1). The federal government is choosing here and now to cooperate with researchers who have destroyed human embryos, and even in some cases to reward them with research grants (since these researchers have the most immediate access to the cell lines thereby created).

Moreover, the link between the government's actions and the destruction of human embryos is even closer here than in the case of vaccine companies using fetal tissue from abortions, because in the present case the taking of human life was done precisely in order to provide cells for research (and in some cases precisely to qualify for federal research grants).

If treatments ultimately result from this decision, Catholics will face a new form of question (2): Whether in conscience they can accept such treatments that rely on the destruction of human life. Here the moral dilemma will be even more difficult, because in this case human life was destroyed specifically to obtain these cells for research and treatment. Use of embryonic stem cells in successful treatments will increase the demand for future destruction of embryos to provide an adequate supply of tissue for thousands or millions of patients. That will pose a new and serious moral dilemma for pro-life Americans who suffer from serious diseases.

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Embryonic Stem Cell Research and Vaccines using Fetal Tissue

Embryonic Stem Cells – Definitions, Use, and Research

Embryonic Stem Cells | Posted by admin
Apr 28 2019

Embryonic stem cells are cells that can give rise to all of the tissues types that form the human body.These stem cells are supporting research into new drugs, being explored for disease reversal, and being utilized to create healthy new tissue to heal injuries.

Embryonic stem cells are also controversial to produce, which has substantially limited their use.Learn more about these cells below.

In this article:

Embryonic stem cells are unique cells that exist in an early-stage embryo. During pregnancy, they develop into all of the cells and tissues that form the fetus and the newborn it grows into.

Embryonic or otherwise, stem cells differ from other types of cells and represent a fraction of the trillion of cells that compose the human body. Unlike regular cells, embryonic stem cells can reproduce. They can also turn into different kinds of cells, known as differentiation.

These pluripotent stem cells boast special characteristics that often make them better suited for therapeutic purposes than adult stem cells. Its helpful to remember that adult stem cells can also refer to those in newborns and children. The term simply means that the cells are sourced from a human being after a live birth This makes adult stem cell types non-controversial.

The embryos used to create embryonic stem cells come from in vitro fertilization clinics. These embryos would have otherwise been destroyed or discarded as medical waste by the fertility clinic, because they were not chosen for implantation into a mother or surrogate.

Because they are created from embryos, some people are opposed to research involving embryonic stem cells. Other groups, like the Michael J. Fox Foundation, have been highly favorable toward embryonic stem cell research, because the cells are versatile and have great potential for use in regenerative medicine to cure a range of diseases that burden the human race, such as Parkinsons disease, Alzheimers disease, multiple sclerosis (MS), and more.

To gauge what percentage of the public supports embryonic stem cell research, BioInformant posted a Twitter poll on September 16, 2018. The results of this poll are shown below, showing that slightly more than half of respondents support embryonic stem cell research (58%) and an astounding 84% of respondents either support embryonic stem cell research or think it depends on the situation.

Human embryonic stem cells (hESCs) are pluripotent cells that are derived from embryos at fertility clinics and provided with informed donor consent. Embryonic stem cells are usually harvested shortly after fertilization (within 4-5 days) by transferring the inner cell mass of the blastocyst into a cell culture medium, so that the cells can be multiplied in a laboratory.

Pluripotent cells can give rise to all of the cell types that form the human body, making them very powerful for use within regenerative medicine applications.

As the name suggests, human embryonic stem cells are derived from human embryos, which makes them controversial to produce. Thankfully, these cells are only produced from embryos that would otherwise treated as biological waste produced as a byproduct of the assisted fertility process at fertility clinics.

In contrast, embryonic stem cells can also be derived animal sources, such as from mice, rats, monkeys, and more. These animal derived embryonic stem cells are substantially less controversial for use in research applications. Unfortunately, they also have few therapeutic applications, because there are immunological issues associated with using animal cells within humans.

If @UWMadison is the birthplace of human embryonic stem cells, then the Primate Research Center is the cradle. Marina Emborg A starring role for nonhuman primates in the stem cell story fantastic article

Speaking of Research (@SpeakofResearch) September 13, 2018

Researchers harvest human embryonic stem cells from a blastocyst. Thats the scientific name for an embryo in its earliest form, usually 4-5 days past the fertilization stage. In traditional human pregnancy, the blastocyst stage occurs before the embryo reaches and implants within the mothers uterine wall. At this blastocyst stage, the young embryo has about 150 cells. That makes it easy to isolate them for harvesting.

Blastocyst embryos used for harvesting come from embryos created in fertility clinics, not from a womans uterus. Researchers harvest them with the permission of the sperm and egg donors. Once created, the blastocyst embryos can be preserved indefinitely under laboratory conditions.

Researchers harvest the embryo stem cell at the Day 4 or 5 stage. This time frame is crucial, because it is just after the embryo begins dividing multiple cells within itself, but before those cells begin to differentiate.

To differentiate, as the name suggests, means that the cells begin to become specific to one of the three germ layers. However, an inner cell mass (ICM) does form, within a protective outer layer. The cells get harvested from the ICM after scientists penetrate the outer layer.

Scientists first isolated embryonic stem cells in mice in 1981. Much later, they isolated human embryonic stem cells in 1998. Ethical concerns caused much of that gap in research. For moral and practical reasons, the cellsneededto be harvested from embryos thatdidnt come from a pregnant woman.

Fortunately, by the late1990sfertility clinics perfected many new techniques. Those breakthroughs not only meant higher success rates for hopeful couples, they also created more viable embryos from which stem cells could be extracted. The clinics reportedly had about 11,200 embryos in frozen storage that would otherwise be discarded. Instead, the clinics donated some for stem cell research.

Scientists cleared the second major research hurdle in 2001 when the federal government decided to fund embryonic stem cell research. This support allowed various research facilities to obtain and study the embryos.

The breakthrough came at an exciting time, because researchers had only recently learned how to extract the needed embryonic stem cells. The mouse-related discovery in 1981 was important. However, those cells differ too much from human embryonic stem cells to put the knowledge to use. In the interim, researcher achieved breakthroughs with other primates.

Scientists value embryonic stem cells because of theirpluripotent properties. For the non-scientists among us, that means they cells are highly versatile and capable of becoming a wide range of cell types. Many stem cells can only produce exact copies of themselves for example, blood cells to blood cells, bone cells to bone cells, and so forth. apluripotentstem cell is defined as a cell that can change itself into nearly any cell or tissue type within the human body.

In practice, this allows scientists to turn embryonic stem cells into any part of the body. Cells develop in layers, known as germ layers. Humans have three germ layers. The outermost, the ectoderm, consists of skin and nervous system. Next, the mesoderm, make up bones, blood, muscles,and the genial system. The innermost germ cell layer, theendoterm, includes lung and digestive system cells. Taken together, adult humans have 220 different types of cells within those three layers.

Embryonic stem cells keep generating new cells, making them useful. These reproductive abilities mean the stem cells ultimately form tissue to can be used to help patients. The tissues can also be used by scientists to conduct medical research.

While embryonic stem cells are pluripotent stem cells, there are also two other types of stem cells: totipotent and multipotent cells. What is the difference between they cell types? The answer is simple.

Totipotentstem cells are the most versatile stem cell type, because they are formed shortly after fertilization of an egg cell by a sperm cell. They can become all of the cells of the human body, as well as the cells of the embryo and developing fetus.At about four days into development, these totipotent cells specialize slightly, becoming pluripotent stem cells, such as the embryonic stem cell.

Later, multipotent stem cells form, which are again more limited in what they can become.They cells types usually prefer to become cells of a certain class or category.

For example, hematopoieticstem cells (HSCs) are a type of multipotent stem cell that prefer to become cells of the blood and immune system, although it it possible to induce them to become other cell types.

Scientists only recently began to understand how many diseases and conditions embryonic stem cells may be able to treat. Research is still ongoing. Because so many health problems involve the dysfuntion or death of cells, human embryonic stem cells may be able to reverse the progress of these diseases.

In the future embryonic stem cells may contribute to the treatment of Parkinsons disease, heart disease, diabetes, spinal cord injuries, vision problems, or other diseases and conditions.

How Can Stem Cell Therapy Help You? | What Diseases Can Be Treated with Stem Cell Therapy

BioInformant (@StemCellMarket) June 23, 2018

Suitable subjects for testing present a major stumbling block toward radical breakthroughs in pharmacology. Early versions of medicinal drugs and surgical procedures carry potential side effects that may not come out until testing actually occurs. This is obviously problematic for any human subjects, especially for those already frail from the disease or injury.

That is why human embryonic stem cells present a radical opportunity for new breakthroughs in drug therapy and surgical procedures. Scientists can grow healthy tissue from embryonic stem cells to see how that tissue responds to these therapies. They can also give that tissue specific disorders, then attempt to cure it with new medical breakthroughs.

Human embryonic stem cells have the ability to transform into other cells. From those new cells, scientists can create heart tissue, bone marrow tissue, blood samples or other body parts which they need to test. In doing so, they can avoid experimenting on patients.

In addition to embryonic stem cells, several broad categories of stem cells exist, including:

Stem cell research has been going on for over 50 years because stem cells have a unique ability to divide and replicate repeatedly. In addition, their unspecialized nature makes them of great interest for regenerative medicine applications.

Adult stem cells also hold more great promise. In healthy humans, adult stem cells produce new cells when needed, to maintain normal functions and repair minor wounds and disorders. However, they are considered less versatile, because they cannot differentiate into all tissue types that compose the human body like embryonic stem cells.

Adult stem cells typically have a preference to become certain tissues within the human body. For example, hematopoietic stem cells (HSCs) are a widely researched adult stem cell type. Although HSCs prefer to become cells of the blood and immune system, they can sometimes be coaxed to become other cell types.

Another example of the utility of adult stem cells is the success of bone marrow transplants. Bone marrow transplants treat patients with cancer whose immune systems have been compromised by chemotherapy or radiation. A bone marrow transplant from a donor or from the patient, prior to treatment uses bone marrow stem cells to help generate new cell production.

Over time, researchers have discovered adult stem cells in many sites throughout the human body. Adult stem cells are now known to exist in the blood, bone marrow, fat (adipose) tissue, dental pulp, neural tissue, and many other sites.

These stem cells are capable of positively affecting a wide range of diseases through either tissue repair or signalling mechanisms. Particular stem cells types, like mesenchymal stem cells, can lower inflammation, reduce scarring, and improve immune function.

What changed? Until recently, adult stem cells were considered inherently limited, because they do not differentiate into all of the cells that compose the human body. However, researchers have found a variety of ways to activate both cell division and differentiation. This ability to grow more healthy tissue in laboratory conditions could substantially alter the future of medicine.

Access to embryonic stem cells is inherently limited to the number of available samples from fertility clinics. Yet adult donors are more plentiful. This is particularly true if a patient can act as his or her own donor.

What are embryonic stem cells and how can they help heal diseases? Watch the video below to learn more:

What do you want to know about embryonic stem cells? Share your thoughts with us below.

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Embryonic Stem Cells Definitions, Use, and Research

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Embryonic Stem Cells - Definitions, Use, and Research

Will Embryonic Stem Cells Ever Cure Anything? – MIT …

Embryonic Stem Cells | Posted by admin
Apr 28 2019

When his son Sam was diagnosed with type 1 diabetes at six months of age, Doug Melton was incredulous. I remember at night, my wife and I pricking his heel, and saying No, this cant be, this cant be, he says. It felt like we had lost the lottery.

Later, his daughter would receive the same diagnosis. By then, Melton had already dropped what he was doingstudying frog eggs at Harvardand launched an effort to grow pancreatic cells from scratch in his lab. The beta cells of the pancreas are the ones killed off in type 1 diabetes, and Melton reasoned he could replace them using new tissue manufactured from embryonic stem cells.

Meltons effort, involving a 30-person lab at Harvard and a startup company, Semma Therapeutics, which he named after his children, Sam and Emma, is one of the most costly and sustained efforts to turn stem cells into transplantable tissue, an attempt that Melton admits has been full of false starts and dead ends. The public definitely doesnt appreciate that much of science is failure, he says.

In fact, no field of biotechnology has promised more and delivered less in the way of treatments than embryonic stem cells. Only a handful of human studies has ever been carried out, without significant results. The cells, culled from IVF embryos, are capable of developing into any other tissue type in the body, and therefore promise an unlimited supply of replacement tissue.

Sounds simple, but it hasnt been. It took Melton and his team 15 years to unveil each molecular step required to coax a stem cell into a pancreatic beta cell able to sense glucose and secrete insulin. The recipe uses a cocktail of chemicals and a three-dimensional incubation system, tall spinning flasks brewing what looks like murky red Gatorade, that within 30 days can direct the differentiation of stem cells into fully functional beta cells.

Earlier this year, Melton was finally able to demonstrate he could control blood glucose levels of mice for six months using transplants of human beta cells. He thinks he can do that in humans and stretch the therapeutic effect out to a year, a goal thats been turned over to Semma, which is designing an implantable pouch to hold and protect the cells.

Over the last two years, Semma has raised just under $50 million from venture capital firms, California's stem-cell agency, and corporate partners including Novartis and Medtronic. William Sahlman, a Harvard Business School professor who sits on Semma's board, says people are prepared to put very large amounts of money on the experiments. One reason: the global market for insulin exceeds $30 billion a year. Tests strips and monitors might double that.

Because their bodies mount an immune attack on the pancreatic cells that regulate blood glucose, type 1 diabetics are constantly measuring their blood sugar levels with finger pricks and injecting insulin multiple times a day. Their lives can be foreshortened by more than a decade. You could almost say that cellular therapy is the natural solution, Melton says. Its not the technological solution. Its not the Google solution. Its natures solution to the problem. Youre providing the cell which is missing.

Several companies are attempting a tech solution, however, by using electronics to build an artificial pancreas that combines a continuous glucose monitor, an insulin pump, and a sensor with an algorithm to control dosing. Medtronic is nearing FDA approval with one such closed loop system; its smartphone-sized MiniMed 670G performed well in early trials. One of Googles sister companies, Verily, is itself developing glucose-sensing contact lenses and ultra-thin sensors.

San Diego-based ViaCyte, working with Johnson & Johnson, was first to try pancreatic cells derived from embryos in people. It has built an implantable packet of immature cells, which it hopes will differentiate inside the body, and last year opened a clinical trial to test the idea.

Semma also thinks it needs to turn embryonic stem cells into not only insulin-secreting beta cells, but a full-fledged isletthe cluster of cells that includes the alpha, beta, delta, and ancillary cells normally found in a pancreas. Thats a complex objective but one that closely mimics biology. Theres a reason during evolution that these cells are adjacent to one another, says Felicia Pagliuca, Semma's cofounder and a veteran of Meltons lab.

In order to deliver their lab-grown islet to diabetics, Semma is developing prototypes of an iPhone-sized, retrievable packet whose materials insulate it from the immune system, so that patients dont have to take immune-suppressing drugs, as they would if they had a kidney transplant. Christopher Thanos, Semma's vice president of delivery, says his team is modeling physiological processes inside and around the device to experiment with different rates of oxygen, nutrients, and insulin diffusion.

Some outside experts think protecting the cells will not be possible. I'm not optimistic that encapsulation is going to provide the answer, says David Cooper, a professor of surgery at the University of Pittsburgh working on growing human islets in pigs. I personally don't think a device is ever going to be successful. It's impossible to keep all the injurious agents out, he says, referring to the cytokines, antibodies, and other compounds the body releases in response to a foreign body. There's really very little evidence that a capsule can protect you completely from an immune response.

The prospect of surgery every year for the rest of your life is also a practical concern. How many diabetics would sign up for 50, 60, 70 surgeries over the course of a lifetime? What will be the effect of repeated scarring around the surgical site? Melton says the inconvenience of surgery has to be weighed against the thousands of finger pricks and injections that diabetics must administer every year. My kids say once a month they wouldnt hesitate. I think thats a bit extreme, he says. But if it was twice a year, I think thats a go.

If the device does not work, Semma has a backup plan of sorts. It received a $5 million grant from CIRM, the California stem-cell agency, to manufacture islets out of a patient's own tissue using induced pluripotent stem cells. That is a process by which adult cells, like skin cells, are reprogrammed into stem cells. Such matching cells wouldnt be rejected by the body as foreignand might not need as much protectionalthough they probably would not avoid damage by the processes that cause type 1 diabetes in the first place. Semma believes they could help a fraction of patients whose diabetes has different causes.

Semma still has no timeline for when its implantable biotech pancreas could be ready. That means Melton's children will have to wait a while longer. Im sorry it takes so long, says Melton, but it is going to work.

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Will Embryonic Stem Cells Ever Cure Anything? - MIT ...

Creating Embryonic Stem Cells Without Embryo Destruction

Embryonic Stem Cells | Posted by admin
Apr 23 2019

By: Ian Murnaghan BSc (hons), MSc - Updated: 12 Sep 2015 | *Discuss

One of the biggest hurdles in stem cell research involves the use of embryonic stem cells. While these stem cells have the greatest potential in terms of their ability to differentiate into many different kinds of cells in the human body, they also bring with them enormous ethical controversies. The extraction of embryonic stem cells involves the destruction of an embryo, which upsets and outrages some policy makers and researchers as well as a number of public members. Not only that, but actually obtaining them is a challenge in itself and one that has become more difficult in places such as the United States, where policies have limited the availability of embryonic stem cells for use.

Although researchers have focused on harnessing the power of adult stem cells, there have still been many difficulties in the practical aspects of these potential therapies. In an ideal world, we would be able to use embryonic stem cells without destroying an embyro. Now, however, this ideal hope may actually have some realistic basis. In recent medical news, there has been important progress in the use of embryonic stem cells.

There are still many more tests and research that must be conducted to verify the safety and reliability of the procedure but it is indeed hopeful that funding can now increase for stem cell research. If you are an avid reader of health articles, you will probably be able to stay up-to-date on the latest developments related to this medical news. This newest research into embryonic stem cells holds promise and hope for appeasing the controversy around embryonic stem cell use and allowing for research to finally move forward with fewer challenges and controversies. For those who suffer from one of the many debilitating diseases and conditions that stem cell treatments may help or perhaps cure one day, this is welcome news.

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Creating Embryonic Stem Cells Without Embryo Destruction

What Are Stem Cells? –

Embryonic Stem Cells | Posted by admin
Apr 19 2019

The term "stem cells" has become part of the mainstream lexicon, likely to be overheard in conversations anywhere from a baseball game to cocktail get-togethers. But what exactly are these cells?

Along with phrases such as "that's just immoral" or "stem cells could be the end-all cure," one could easily weave in some technical tidbits about these microscopic, yet significant, cells.

Stem cellsare considered the "engine" cells of regeneration in that they are self-renewing and able to duplicate, or clone, themselves. These special cells are used in the rapidly growing field of regenerative medicine to halt or even reverse chronic diseases. Regenerative medicine seeks torepair or replace tissues or organsthat have been damaged by trauma, disease or congenital defects, according to theMcGowan Institute for Regenerative Medicineat the University of Pittsburgh.

There are three types of stem cells: embryonic, umbilical cord (also known as mesenchymal, or MSC), and adult stem cells. Embryonic stem cells are considered pluripotent, meaning they can give rise to all of the cell types that make up the human body. Cord and adult stem cells are multipotent, which means that they are able to develop into more than one cell type, but they are more limited than pluripotent cells, according toNYSTEM (New York Stem Cell Science).

In the United States, cord and adult stem cells are the only ones used in regenerative medical procedures. Due to ethical controversy, embryonic stem cells are not used in clinical practice but can be used for research purposes. [How Stem Cell Cloning Works (Infographic)]

Adult stem cells which can be taken from bone marrow, blood or fat are mostly free of ethical controversy, but they have limited potential. As we get older, not only do our stem cells lose functionality, but we have far fewer of them. Researchers estimate that newborns have 40 times more stem cells in their bone marrow compared to a 50 year old, according to a 2009 study in theJournal of Pathology. In addition, adult stem cells may be subject to DNA abnormalities caused by sunlight, toxins and errors associated with making more DNA copies over the course of a lifetime, according to theNational Institutes of Health (NIH).

Cord stem cells can be harvested from the umbilical cord after birth with the mother's permission. This tissue, which is typically discarded, can be donated to science for use in research or medicine, or placed in a cord bank in case the mother or child may need it one day.

Cord stem cellsare much more efficient at replicatingonce removed from the body compared to adult stem cells. For example, when placed in a petri dish with the proper nutrients, one cord stem cell will multiply into 1 billion cells in 30 days, whereas one adult stem cell will multiply into only around 200 cells in 30 days, according to a 2011 study published in the journalOrthopedics.

Doctors use cord stem cells to treat autoimmune conditions, such aslupus,rheumatoid arthritisandmultiple sclerosis, as well as chronic infections such asHIV, herpes and Lyme disease, according toAMA.

Embryonic stem cells hold the most promise for treating diseases, but heated debate abounds over the ethics of using them.Human embryonic stem cellsare derived from eggs fertilized in vitro (outside of the body) and are somewhat pristine. These pluripotent stem cells are prized for their flexibility in being able to morph into any human cell.

When embryonic stem cells are grown in a laboratory under certain conditions for several months, they can remain unspecialized and produce millions of stem cells indefinitely. The resulting batch of cells is referred to as a stem-cell line.

The NIH said 64 embryonic stem-cell lines existed as of August 2001 when President Bush announced the federal policy describing the constraints on funds for stem-cell research. In March 2009, however, President Obama officially removed the restrictions placed by President Bush on federal funding for research on embryos. Although it's been contested, the policy remains in effect withstrict guidelines in place by the NIH.

Scientists can now reprogram adult stem cells to become more like embryonic stem cells. These are known as induced pluripotent stem cells (iPSCs). But since iPSCs are still adult stem cells, they carry the risk of having abnormalities. Much more research is needed on iPSCs, but scientists hope to use them in transplantation medicine, according to theNIH.

Additional resources:

This article was updated on April 15, 2019 by Live Science Contributor Traci Pedersen.

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What Are Stem Cells? -

Embryonic Stem-Cell Research Reaches Moral, Medical Dead End

Embryonic Stem Cells | Posted by admin
Apr 08 2019

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 Cells | Posted by admin
Apr 02 2019

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

Embryonic Stem Cells | Posted by admin
Mar 30 2019


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 –

Embryonic Stem Cells | Posted by admin
Mar 20 2019

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,


"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.


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,, accessed July 2004.


"'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.


"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.]


"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


"'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


"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.


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.


"[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.


"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


"[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


"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.


"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,


"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


"'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

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Practical Problems with Embryonic Stem Cells -