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September 18, 2017| Stem Cell Orthopedic Institute of Texas Team | STEM CELL THERAPY

If you have any interest in stem cells, you may be familiar with the debate on embryonic stem cells. Stem cells have been researched since the mid-1900s. While adult stem cells have proven to be safe and effective, embryonic stem cells are banned for human use in the United States.

As such, at the Stem Cell Orthopedic Institute, we exclusively use adult stem cells. For a complete description of our process, please visit our procedure overview.

While we do not use embryonic stem cells in America, it is important to remember how we got to this point to inform what choices we make going forward. Heres the truth about embryonic stem cells:

Just like the name sounds, embryonic stem cells are derived from embryos. Most embryonic stem cells come from embryos that develop from eggs that were fertilized in vitro (in an in vitro fertilization clinic) and then donated for research purposes with the donors consent. These stem cells are not derived from the eggs that have been fertilized in a womans body.

Fertilization usually occurs in the oviduct. The few days after the embryo travels down the oviduct and into the uterus, a series of cleavage divisions will occur. The embryo is a ball of around 100 cells at this point (called a blastocyst). The outer layer of cells forms the placenta and is called the trophectoderm. The cells during this stage are undifferentiated, which means that they do not look or act like the specialized adult cells, and they are not yet committed to becoming any specific type of differentiated cell.

The first differentiation event occurs at around five days of development which is when an outer layer of cells separates from the inner cell mass (ICM). The ICM cells have the potential to generate any cell type, but once they have been implanted, they are quickly depleted as they differentiate into other cell types with limited developmental potential. However, the ICM cells can continue to multiply and endlessly replicate themselves, while maintaining the developmental potential to form any cell only if the ICM is removed from its normal embryonic environment and cultured under proper conditions.

Embryonic stem cells have a never-ending lifespan with an almost unlimited developmental potential. Embryonic stem cells are pluripotent, which means that can grow into any one of the three primary germ layers: ectoderm, endoderm, and mesoderm. These cells have the potential to form any type of cell in the body, from muscle to nerve to blood. Embryonic stem cells provide endless possibilities for researchers.

In 2001, President George W. Bush allowed federal funding for limited embryonic stem cell research. However, President Barack Obama revoked that statement in 2009 and released Executive Order 13505 to remove the restrictions on federal funding for stem cell research. This allowed the National Institutes of Health (NIH) to fully fund research with embryonic stem cells. The NIH issued guidelines to establish the policy. These guidelines were created to help ensure that all NIH-funded research on human stem cells is morally responsible and scientifically relevant.

Embryonic stem cells are used for many purposes, from basic research to transplantation therapies for various diseases like heart disease, Parkinsons disease, leukemia, and more. Since it is illegal to use human embryonic stem cells, researchers rely on mice and other animals for these cells. Stem cells have to potential to grow new cells to replace damaged organs or tissues, correct portions of organs that work improperly, research causes of genetic defects in cells, research how diseases occur or why certain cells develop into cancer cells and test new drugs for safety and effectiveness.

Research with embryonic stem cells (ESCs) is highly debated and many people have strong opinions about their stance on the issue. Many of the discussions lie around moral and ethical issues. The dilemma forces us to choose between two moral principles: the duty to prevent and alleviate suffering or the duty to respect the value of human life.

Lets take a look at both stances. In order to obtain embryonic stem cells, you must destroy the embryo also meaning that you are destroying a potential human life. On the other hand, embryonic stem cell research could help us find new medical treatments that could help alleviate or end those suffering from many disorders and diseases. The biggest question: which moral principle should have the upper hand? The answer ultimately depends on how you view the human embryo.

Embryonic stem cells also have a high oncogenic potential meaning it is potentially cancerous. Since these cells have the possibility to transform into practically any cell, there is a possibility they can form tumors in patients.

At the Stem Cell Orthopedic Institute of Texas, we never use embryonic stem cells only adult stem cells. Our patients health and safety is our priority. Rest assured, our doctors will give you the personalized attention you deserve. To learn more about our stem cell treatments or to schedule an appointment, call us at 210-293-3136.

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Truth About Embryonic Stem Cells | Stem Cell Orthopedic ...

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Dr. Francis Collins has not shown any pro-life leadership at the National Institutes of Health (NIH). In fact, in an interview, Dr. Collins response to a congressional letter outlining pro-life members concerns dripped with condescension, implying that the group of 41 congressmen understood neither the science nor the ethics of embryo and stem cell experiments. Dr. Collins owes us an apology. We know the science, use the scientifically accurate terms and know the ethical facts. Dr. Collins positions at NIH have not been pro-life.

His lack of pro-life leadership might have been expected when he served under the previous administration, which was the antithesis of pro-life. However, now Dr. Collins has agreed to work for President Trump, who campaigned on a pro-life agenda. Will Dr. Collins change his positions and adjust his agenda? When will we have a pro-life NIH Director who reflects the policy of our president?

As one example of the void in pro-life leadership, Dr. Collins designed and oversees the NIH registry of human embryonic stem cell lines, a listing of cells created by destroying young human embryos that are eligible for hundreds of millions in federal taxpayer dollars. Dr. Collins continuously approves cells for this registry, and did so most recently in March and again in June of this year.

The registry has created a cottage industry for those who want to destroy human embryos and then reap taxpayer dollars for their efforts. The establishment of the registry created an incentive for further destruction of young human embryos, under the guise of expanding scientific research and providing more experimental material. Dr. Collins called it important, life-saving research, despite the fact that embryonic stem cells have to this day not saved a single human life nor proven to have any near-term success in patients.

Eight years after its inception, the registry is nothing more than an embryonic charnel house. The stem cell lines sit as names and numbers on the registry, memorial markers to the lives of the human embryos destroyed in the name of science.

Moreover, scientific leaders admit that human embryonic stem cells now serve primarily as references to compare with nonembryonic stem cells in the laboratory. Induced pluripotent stem (iPS) cells, which show the same characteristics as embryonic stem cells, have largely replaced embryonic stem cells. The Nobel-prize-winning iPS cells can be made from virtually any person or tissue, healthy or diseased, more cheaply and efficiently than embryonic stem cells, without destroying the donor of the cells.

After consuming a decade and a half of federal funding, amounting to well over a billion taxpayer dollars, embryonic stem cell research has produced no help for patients. The stem cell registry at NIH and federal funding for it should be foreclosed, and the funds should be redirected to research that shows real hope for patients.

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In previous interviews, Dr. Collins has ignored the gold standard of stem cells for patients: adult stem cell research. Adult stem cells have now treated well over 1 million patients around the globe, including tens of thousands of children. Adult stem cells are the only stem cell option to show authenticated, life-saving success in patients, validated by hundreds of scientific publications.

Yet in a 2009 interview, Dr. Collins touted the one clinical trial approved by the FDA at the time a single trial that showed no benefit to any patient from embryonic stem cells, even to today and ignored over 2,000 adult stem cell clinical trials ongoing at the time (the number of adult stem cell trials now exceeds 3,000). Adult stem cell research is providing real innovation for patients now, and it could use the funding that now goes to dogmatic support for antiquated science. Will Dr. Collins voice his support for adult stem cell research and redirect funding toward patient-focused science.

The House of Representatives has shown tangible support for this idea with the introduction of H.R. 2918, the Patients First Act of 2017. The bill would direct HHS to prioritize adult stem cell research that has the best chance of producing near-term benefits in patients without the creation, destruction, or risk of injury to human embryos. Furthermore, the bill advocates for the ethical approach without authorizing any additional spending.

In addition to refusing to acknowledge the potential of adult stem cell research, Dr. Collins has also supported human cloning to create embryos for experiments. In this scenario, a cloned human embryo would not be allowed to survive and develop, but rather be torn apart for the use of its cells in laboratory tests. Cloning (technically termed somatic cell nuclear transfer) requires the transfer of a cell nucleus into an egg that has had its own nucleus removed. This is the way Dolly the cloned sheep and other cloned animals all began, as cloned embryos.

Yet Dr. Collins takes the unscientific view that a cloned embryo is not really an embryo, because, he says, it was not produced by a sperm and egg coming together. Even the NIH states that the cloning process produces an embryo.

The NIH can be a world leader in successful, ethical science and medicine. But this shift requires a pro-life leader at the helm.

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Embryonic Stem Cell Research Still Hasn't Cured a Single ...

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Doubts have surfaced about a landmark paper claiming that human embryos were cleared of a deadly mutation using genome editing. In an article1 posted to the bioRxiv preprint server on 28 August, a team of prominent stem-cell scientists and geneticists question whether the mutation was actually fixed.

The 2 August Nature paper2, led by reproductive biologist Shoukhrat Mitalipov at the Oregon Health and Science University in Portland, described experiments in dozens of embryos to correct a mutation that causes a heart condition called hypertrophic cardiomyopathy.

In contrast to previous human-embryo editing studies, Mitalipovs team reported a high success rate at correcting a disease-causing mutation in a gene. The team claimed that the CRISPRCas9 genome editing tool was able to replace a mutant version of the MYBPC3 gene carried by sperm with a normal copy from the egg cell, yielding an embryo with two normal copies. Mitalipovs team also introduced a healthy version of the gene along with the CRISPR machinery, but they found that the corrected embryos had shunned it for the maternal version.

But there is reason to doubt whether this really occurred, reports a team led by Dieter Egli, a stem-cell scientist at Columbia University in New York City, and Maria Jasin, a developmental biologist at Memorial Sloan Kettering Cancer Center in New York City. George Church, a geneticist at Harvard Medical School in Boston, Massachusetts, is another co-author.

In their bioRxiv paper, Egli and Jasin and their co-authors say that there is no plausible biological mechanism to explain how a genetic mutation in sperm could be corrected based on the eggs version of the gene. More likely, they say, Mitalipovs team failed to actually fix the mutation and were misled into thinking they had by using an inadequate genetics assay. Egli and Jasin declined to comment because they say they have submitted their article to Nature.

The critique levelled by Egli et al. offers no new results but instead relies on alternative explanations of our results based on pure speculation, Mitalipov said in a statement.

But other scientists contacted by Nature's news team shared the Egli team's concerns. (Natures news team is editorially independent of its journal team.) Reproductive biologist Anthony Perry at the University of Bath, UK, says that after fertilization, the genomes of the egg and sperm reside at opposite ends of the egg cell, and each is enshrouded in a membrane for several hours. This fact, Perry says, would make it difficult for CRISPR-Cas9 to fix the sperms mutation based on the eggs version of the gene, using a process called homologous recombination. Its very difficult to conceive how recombination can occur between parental genomes across these huge cellular distances, he says.

Egli and Jasin raise that issue in their paper. They suggest that Mitalipovs team was misled into believing that they had corrected the mutation by relying on a genetic assay that was unable to detect a far likelier outcome of the genome-editing experiment: that CRISPR had instead introduced a large deletion in the paternal gene that was not picked up by their genetic assay. The Cas9 enzyme breaks DNA strands, and cells can attempt to repair the damage by haphazardly stitching the genome together, often resulting in missing or extra DNA letters.

That explanation makes sense, says Gatan Burgio, a geneticist at the Australian National University in Canberra. In my view Egli et al. convincingly provided a series of compelling arguments explaining that the correction of the deleterious mutation by self repair is unlikely to have occurred.

Another possibility Eglis team raise is that the embryos were produced without a genetic contribution from sperm, a process known as parthenogenesis. Mitalipovs team showed that the paternal genome was present in only 2 out of the 6 embryonic stem cell lines they made from gene-edited embryos.

Robin Lovell-Badge, a developmental biologist at the Francis Crick Institute in London, says that it is possible that there is a novel or unsuspected biological mechanism at work in the very early human embryo that could explain how Mitalipovs team corrected the embryos genomes in the manner claimed. He would first like to hear from Mitalipov before passing judgement. It simply says that we need to know more, not that the work is unimportant, Lovell-Badge says of Egli and Jasins paper.

In the statement, Mitalipovs said his team stands by their results. We will respond to their critiques point by point in the form of a formal peer-reviewed response in a matter of weeks.

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Doubts raised about CRISPR gene-editing study in human embryos - Nature.com

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| Marlowe Hood |

PARIS (AFP) Lab monkeys with Parkinsons symptoms regained significant mobility after neurons made from human stem cells were inserted into their brains, researchers reported Wednesday in a study hailed as groundbreaking.

The promising results were presented as the last step before human clinical trials, perhaps as early as next year, the studys senior author, Jun Takahashi, a professor at Kyoto University, told AFP.

Parkinsons is a degenerative disease that erodes motor functions. Typical symptoms include shaking, rigidity and difficulty walking. In advanced stages, depression, anxiety and dementia are also common.

Worldwide, about 10 million people are afflicted with the disease, according to the Parkinsons Disease Foundation.

Earlier experiments had shown improvements in patients treated with stem cells taken from human foetal tissue and likewise coaxed into the dopamine-producing brain cells that are attacked by Parkinsons.

Dopamine is a naturally occurring chemical that plays several key roles in the brain and body.

But the use of foetal tissue is fraught with practical and ethical problems.

So Takahashi and his colleagues, in a medical first, substituted so-called induced pluripotent stem cells (iPSCs), which can be easily made from human skin or blood. Within a year, some monkeys who had could barely stand up gradually recovered mobility.

They became more active, moving more rapidly and more smoothly, Takahashi said by email. Animals that had taken to just sitting start walking around in the cage.

These findings are strong evidence that human iPSC-derived dopaminergic neurons can be clinically applicable to treat Parkinsons patients, he said.

Experts not involved in the research described the results as encouraging.

The treatment, if proven viable, has the potential to reverse Parkinsons by replacing the dopamine cells that have been lost a groundbreaking feat, said David Dexter, deputy research director at Parkinsons UK.

Not only did the new cells survive but they also integrated with the existing neuronal network, he said.

Neurons made from foetal tissue grafted into brains have been known to survive for more than a decade, and the researchers said they expected those derived from iPSCs to last just as long.

Tilo Kunath, Parkinsons Senior Research Fellow at the University of Edinburgh, said the outcome was extremely promising, and highlighted the advantage of avoiding stem cells extracted from human foetal tissue.

It means that this therapy can be used in any country worldwide, including Ireland and most of South America, where medical use of human embryonic stem cells is banned.

The results, reported in the journal Nature, were not the same for the dozen monkeys in the experiment, each of which received donor neurons from a different person.

Some were made with cells from healthy donors, while others were made from Parkinsons disease patients, said lead author Tetsuhiro Kikuchi, also from Kyoto University.

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Study shows human stem cells restore mobility in Parkinson's monkeys - Borneo Bulletin Online

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Sofa Vergaras embryos are citizens of California.

Christopher Polk/Getty Images for TNT

After years of battling ex-fiance Sofa Vergara in court for custody of a pair of frozen embryos they once made together, condiment entrepreneur Nick Loeb might finally be out of luck. Last week, a federal judge in Louisiana dismissed Loebs suit, saying that the embryos are citizens of California, where Vergara and Loeb conceived and froze them. Thus, the judge ruled, embryos have no legal standing to sue in Louisiana, the only state that gives embryos the right to sue and be sued.

Christina Cauterucci is a Slate staff writer.

Embryos are frozen when they are just clumps of a few dozen cells, equivalent to a vaginally inseminated egg that would still take another week to become embedded in the uterine wall. Louisiana law deems these cells juridical personsnot quite human beings, but deserving of legal rights. In Louisiana, embryos are not merely property of the two people who made them, so any legal disputes must meet the best interest of the in vitro fertilized ovum.

Thats the most likely reason why Loeb sued Vergara in Louisiana, despite the fact that neither party maintains a residence there.* (Loeb says he chose the state because the couple broke up there; he dropped an earlier California suit because he didnt want to name his previous girlfriends whod had abortions.) Actually, Loeb didnt exactly sue Vergarathe embryos, Emma and Isabella, did. Plaintiff EMMA is a female human being at the embryonic stage of life, five days old developmentally, the right to live suit read, claiming that Vergara had effectively abandoned and chronically neglected her children by keeping them frozen in a medical tank since 2013. Though Vergara and Loeb had signed a contract when they were together agreeing that the embryos would never be implanted anywhere without both parties consent, Loeb wanted to nullify the agreement and implant them in a surrogate.

Over the past couple of years, the Vergara-Loeb embryo battle has become a proxy fight for anti-abortion advocates who think frozen embryos should be treated like people. Anti-abortion groups have funded or filed amicus briefs in the embryo disputes of split-up couples, including the case of a Missouri woman named Jalesia McQueen. In the middle of her own court battle over two frozen embryos (Noah and Genesis) with an ex-husband who wanted to dispose of them, McQueen founded an organization called Embryo Defense to advocate for all excess embryos in legal limbo. She aggregates news on the Vergara-Loeb case and uses their photos in images made for sharing on social media. The graphics say things like Sofia says its selfish to let the embryos be born without both parents being in a loving relationship. Shouldnt both parents just love the child? and Please pray for Sofia Vergara and those she called her frozen babies, that shed open her heart so they could be a blessing in her life. One pairs a picture of Loebs face with the question what about a fathers right to choose?

The concept of a fathers right to procreate without input from the woman whose egg created the embryo is a favorite rallying cry of the embryo-protector set. Loeb himself made this argument in a 2015 New York Times op-ed with the magnificent headline Sofa Vergaras Ex-Fianc: Our Frozen Embryos Have a Right to Live. A woman is entitled to bring a pregnancy to term even if the man objects, Loeb wrote. Shouldnt a man who is willing to take on all parental responsibilities be similarly entitled to bring his embryos to term even if the woman objects?

The federal judges decision against Loeb is only the latest in a string of disappointing court losses for those who believe embryos should be treated like people. When Barack Obama lifted a ban on federal funding for embryonic stem cell research in 2009, he was hit with a lawsuit from one Mary Scott Doe, a frozen embryo symbolizing all existing frozen embryos. A federal appeals court ruled that Doe had no standing as an amorphous class that could not prove any actual harm. In 2015, a California Superior Court judge ruled that a contract a divorced couple signed at the medical center where they created the embryo prevented either party from taking unilateral custody of the embryos unless one of the parties died. Even McQueen, the founder of Embryo Defense, lost her suit late last year when a St. Louis court ruled that embryos are marital property of a special character, not human beings with unalienable rights.

That St. Louis case might be the most promising decision yet for those who believe that no person should be able to incubate an embryo without the consent of the other person whose genetic material it carries. The others, which rest on the tenets of contract law, legal standing, and jurisdiction, say more about how the suits were filed than what rights adults have to the embryos they create. Still, Loebs loss could set a welcome precedent in these kinds of cases: Jurisdiction-shopping embryo protectors might find Louisiana to be a less hospitable home for a lawsuit than theyd imagined.

*Correction, August 31, 2017: This piece originally referred to "the most likely reason why Loeb sued Vergara in California, despite the fact that neither party maintains a residence there." It should have said Louisiana.

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Sofa Vergara's ex might finally be out of luck in his battle for custody ... - Slate Magazine (blog)

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Cardiac predecessor cells appear to rejuvenate the hearts of older animals, according to a recent study from Cedars-Sinai Heart Institute that may lead to tests in humans.

Signs of rejuvenation in rats included a 20 percent increase in exercise capacity, faster regrowth of hair, and lengthening of the protective caps of chromosomes.

The study used cardiosphere-derived cells, or CDCs, which are like stem cells, but can only develop into heart cells. These cells are already being used in a human clinical trial to repair damage from heart attacks. The trial is being conducted by Beverly Hills-based Capricor in several hospitals, including Scripps La Jolla.

Since these cells have already been found to be safe, it should be fairly straightforward to extend testing from repairing heart damage in people to rejuvenation, said study leader Dr. Eduardo Marbn. Hes director of the Los Angeles Institute, part of Cedars-Sinai Medical Center. Marbn is also a co-founder of Capricor, publicly traded on Nasdaq.

However, a researcher not involved in the study said that while it was well done, the history of stem cell treatments indicates that proving efficacy in people promises to be far more difficult.

The study used cells taken from newborn rats, injected into the hearts of older, senescent rats. It was published Aug. 14 in the European Heart Journal.

The study is exceptional in both its scope and breadth, said Dr. Richard Schatz, a Scripps Clinic cardiologist involved in the Capricor trial at Scripps La Jolla.

It examines an extraordinary number of variables rarely seen in such studies to ask the question of the impact of CDC (specialized stem cells) on cardiac aging in rats, Schatz said by email. Every parameter of how aging might be studied moved in the right direction, meaning there might be a biologic effect of their cells throughout the body.

Schatz cautioned that scientific excellence doesnt equal clinical success.

The technologys muscle-improving effectiveness could also help patients with Duchenne muscular dystrophy, Marbn said. That use is in clinical testing by Capricor. Early results in patients have been promising enough that more studies are planned.

Capricor clinical trial information is available at http://capricor.com/clinical-trials.

Marbn said the study adds to growing evidence that progenitor cells exert their healing power by secreting chemicals that stimulate repair, not by permanently incorporating themselves into the body. The chemicals are enclosed in tiny vesicles called exosomes that the cells shed.

Until fairly recently, exosomes were dismissed as cellular debris, but are now being appreciated for their role in cell signaling, Marbn said.

There's a staggering number, something like 100 billion to a trillion exosomes per drop of blood, per drop of cerebrospinal fluid, Marbn said. They are plentiful in breast milk. The only thing we know right now is that there is a complex signaling system.

These exosomes travel far beyond the heart to reach skeletal muscle, which is weakened in Duchenne muscular dystrophy, he said.

Schatz said the study provides evidence that the cells exert many different effects beyond those in a single target organ, through the exosomes, seen in humans as well.

This is very good news if you are a rat, but the obvious limitation is how will this play out in humans, Schatz said.

Previous clinical trials of stem cells have been successful in Phase 1 and 2, Schatz said, but fail in Phase 3. So the researchers face a daunting road ahead to demonstrate usefulness in people.

This does not take away from the brilliant science behind this exceptional group of investigators, Schatz said. They should be congratulated for a very thoughtful and expansive look at a fascinating subject, the clinical relevance of which remains to be seen.

The rejuvenation effects to some degree resemble cells created when adult cells are reprogrammed back to being stem cells, Marbn said.

Certain factors are turned on that regress the cells to act like embryonic stem cells. These are called induced pluripotent stem cells, because they can become nearly any cell in the body, a property called pluripotency.

Something like this might be happening through exosome-mediated reprogramming.

We have a suspicion that even though we didn't go about trying to activate those factors, some of them may in fact be turned on by the therapy, Marbn said.

Understanding precisely what is going on will take much more work to sort out, he said. For example, lengthening the protective caps of chromosomes, or telomeres, is presumably caused by production of telomerase, an enzyme that makes them longer. But how?

Knowing the exosomes are involved doesnt narrow it down very much, he said.

We think that there's thousands and thousands of different bioactive molecules within exosomes. And so I can't right now point to, let's say, these five RNAs and say, they're the ones that we think are doing the trick, Marbn said. But somewhere in the genetic instructions in the exosomes are signals that cause telomerase to be activated and elongation of the telomeres.

Even without understanding the precise mechanism, the demonstrated results have been promising enough for Capricor to continue clinical testing in Duchenne muscular dystrophy, Marbn said, even though its outside the companys initial focus on heart disease.

The heart attack research gave mixed messages, he said. Capricor isnt abandoning it, but has given priority to the muscular dystrophy program.

Duchenne muscular dystrophy patients and their parents are more interested in increasing skeletal muscle function than heart function, he said. The disease virtually exclusively affects males, and they often die when quite young.

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Young cardiac cells rejuvenate heart in animal study - The San Diego Union-Tribune

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In an ideal situation, these humanized mice would reject foreign stem cells just as a human patient would.

Wu shares senior authorship of the research, which was published Aug. 22 in Cell Reports, with Dale Greiner, PhD, professor in the Program in Molecular Medicine at the University of Massachusetts Medical School, and Leonard Shultz, PhD, professor at the Jackson Laboratory. Former postdoctoral scholars Nigel Kooreman, MD, and Patricia de Almeida, PhD, and graduate student Jonathan Stack, DVM, share lead authorship of the study.

Although these mice are fully functional in their immune response to HIV infection or after transplantation of other tissues, they are unable to completely reject the stem cells, said Kooreman. Understanding why this is, and whether we can overcome this deficiency, is a critical step in advancing stem cell therapies in humans.

Humanized mice are critical preclinical models in many biomedical fields helping to bring basic science into the clinic, but as this work shows, it is critical to frame the question properly, said Greiner. Multiple laboratories remain committed to advancing our understanding and enhancing the function of engrafted human immune systems.

Greiner and Shultz helped to pioneer the use of humanized mice in the 1990s to model human diseases and they provided the mice used in the study.

The researchers were studying pluripotent stem cells, which can become any tissue in the body. They tested the animals immune response to human embryonic stem cells, which are naturally pluripotent, and to induced pluripotent stem cells. Although iPS cells can be made from a patients own tissues, future clinical applications will likely rely on pre-screened, FDA-approved banks of stem cell-derived products developed for specific clinical situations, such as heart muscle cells to repair tissue damaged by a heart attack, or endothelial cells to stimulate new blood vessel growth. Unlike patient-specific iPS cells, these cells would be reliable and immediately available for clinical use. But because they wont genetically match each patient, its likely that they would be rejected without giving the recipients immunosuppressive drugs.

Humanized mice were first developed in the 1980s. Researchers genetically engineered the mice to be unable to develop their own immune system. They then used human immune and bone marrow precursor cells to reconstitute the animals immune system. Over the years subsequent studies have shown that the human immune cells survive better when fragments of the human thymus and liver are also implanted into the animals.

Kooreman and his colleagues found that two varieties of humanized mice were unable to completely reject unrelated human embryonic stem cells or iPS cells, despite the fact that some human immune cells homed to and were active in the transplanted stem cell grafts. In some cases, the cells not only thrived, but grew rapidly to form cancers called teratomas. In contrast, mice with unaltered immune systems quickly dispatched both forms of human pluripotent stem cells.

The researchers obtained similar results when they transplanted endothelial cells derived from the pluripotent stem cells.

To understand more about what was happening, Kooreman and his colleagues created a new mouse model similar to the humanized mice. Instead of reconstituting the animals nonexistent immune systems with human cells, however, they used immune and bone marrow cells from a different strain of mice. They then performed the same set of experiments again.

Unlike the humanized mice, these new mice robustly rejected human pluripotent stem cells as well as mouse stem cells from a genetically mismatched strain of mice. In other words, their newly acquired immune systems appeared to be in much better working order.

Although more research needs to be done to identify the cause of the discrepancy between the two types of animals, the researchers speculate it may have something to do with the complexity of the immune system and the need to further optimize the humanized mouse model to perhaps include other types of cells or signaling molecules. In the meantime, they are warning other researchers of potential pitfalls in using this model to screen for immunosuppressive drugs that could be effective after human stem cell transplants.

Many in the fields of pluripotent stem cell research and regenerative medicine are pushing the use of the humanized mice to study the human immune response, said Kooreman. But if we start to make claims using this model, assuming that these cells wont be rejected by patients, it could be worrisome. Our work clearly shows that, although there is some human immune cell activity, these animals dont fully reconstitute the human immune system.

The researchers are hopeful that recent advances may overcome some of the current models limitations.

The immune system is highly complex and there still remains much we need to learn, said Shultz. Each roadblock we identify will only serve as a landmark as we navigate the future. Already, weve seen recent improvements inhumanized mousemodels that foster enhancement of human immune function.

Wu is a member of Stanford Bio-X, the Stanford Cancer Institute and the Stanford Child Health Research Institute. He is also the Simon H. Stertzer Professor.

Additional Stanford co-authors are former research assistant Raman Nelakanti; former postdoctoral scholars Sebastian Diecke, PhD, and Veronica Sanchez-Freire, PhD; postdoctoral scholar Ning-Yi Shao, MD, PhD; instructor Elena Matsa, PhD; and associate professor of pathology Andrew Connolly, MD, PhD.

The research was funded by the California Institute of Regenerative Medicine, the National Institutes of Health (grants R01HL132875, R01HL133272, P30CA034196, UC4DK104218 and T32OD01112) and the Helmsley Charitable Trust.

Stanfords Department of Medicine also supported the work.

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Mouse model of human immune system inadequate for stem cell studies - Stanford Medical Center Report

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A human embryo kept alive in the lab for 12 days begins to show signs of early development. The green cells seen here in the center would go on to form the body. This embryo is in the process of twinning, forming two small spheres out of one. Courtesy of Gist Croft, Cecilia Pellegrini, Ali Brivanlou/Rockefeller University hide caption

Four sheep cloned from the same genetic material as Dolly roam the paddocks in Nottingham, England. The University of Nottingham hide caption

Ken (left) and Henry were created using DNA plucked from a skin cell of Melvin, the beloved pet of Paula and Phillip Dupont of Lafayette, La. Edmund D. Fountain for NPR hide caption

In 1954, Dr. Frederick C. Robbins, then chief of pediatrics and contagious diseases at Cleveland Metropolitan General Hospital, was one of three winners of that year's Nobel Prize in medicine. The scientists' work, which led to a vaccine against polio, was performed in human fetal cells. AP hide caption

Ryoji Noyori, a Nobel Prize-winning chemist and president of Japan's prestigious RIKEN research institute, bows at a news conference in Tokyo Tuesday to apologize for the scientific misconduct of a RIKEN colleague. Eugene Hoshiko/AP hide caption

A mouse embryo grows from stem cells made by stressing blood cells with acid. The blood cells are tagged with a protein that creates green light. Courtesy of Haruko Obokata hide caption

After President Obama overturned Bush-era policy restricting federal funding of embryonic stem cell research in 2009, Nebraska Right to Life led a protest of the research outside the University of Nebraska regents' meeting. Nati Harnik/AP hide caption

Human embryos grow in a petri dish two days after scientists in Oregon cloned them from a donor's skin cell. http://www.flickr.com/photos/ohsunews/8726915230/in/photostream//Courtesy of OHSU Photos hide caption

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embryonic stem cells : NPR

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According to the Leukemia & Lymphoma Society (LLS), one person in the United States is diagnosed with a blood cancer every 3 minutes. One person dies approximately every 9 minutes due to this illness.

Blood cancers affect the blood, bone marrow, and lymphatic system. Most of these cancers originate in the bone marrow where new blood cells are produced. .

Our bone marrow produces three types of blood cells: red blood cells, white blood cells, and platelets. However, cancer in the blood occurs when an abnormal type of blood cell goes into an uncontrolled growth and disrupts the normal blood cell development.

The three main types of blood cancers are:

Now, theres news that vitamin C can help fight blood cancer.

Luisa CimminoandBenjamin Neelat the New York University School of Medicine and their colleagues have discovered that, by injecting vitamin C, cancer growth could be prevented.

According to the researchers, blood cancers like acute and chronic leukemia are caused by the mutation of a gene called tet methylcytosine dioxygenase 2 or TET2. This gene is responsible for ensuring the healthy growth of certain stem cells for the production of white blood cells. But, when TET2 mutation occurs, cell growth goes haywire and leads to cancer.

In their mice experiment, the animals were given variableTET2function through genetic engineering. The researchers discovered that cancer is induced with 50 per cent reduction in TET2 activity, and it continues to develop when the said gene remained at a low level.

However, when TET2 was restored, the gene stopped the uncontrolled growth and killed the cancerous cells.

After such findings, what the team needed to find next was something to reactivate TET2. And they opted to use vitamin C, which has the potency to affect embryonic stem cells.

For 24 weeks, they injected a group of mice which had low TET2 with very high dose of vitamin C daily. This slowed the progression of blood cancer. But, in the case of another group of mice which did not receive vitamin C injections, they showed signs of developing leukemia.

Moreover, to test the efficacy of vitamin C, the researchers added it to a cancer drug to which they exposed human leukemia cells in a lab dish. It proved very effective.

With this discovery, the team is hoping that vitamin C would be used in cancer therapies. It would especially help older people with blood cancer whose immune system are too weak to undergo chemotherapy. But, this would have to be done intravenously. Just taking in large doses of vitamin C would not prevent cancer since the body excretes it through urine when its already above 500 milligrams.

Still, this is a very important study that will definitely have a very lasting impact on the field, notes Ulrich Steidl of the Albert Einstein College of Medicine, adding that it will likely inspire a lot of scientists and translational investigators to think about similar strategies and to go after these pre-leukemic stem cells, which, in [Steidls] opinion will be critical if were ultimately aiming for a cure.

For healthy people, or those who want to boost their immune system, experts recommend taking vitamin C supplements twice a day for better absorption.

Original post:
Injections of Vitamin C Could Help Fight Blood Cancer - Wall Street Pit

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To the Editor:

This is in response to Renee Klugmans Aug. 9 letter Disappointed by Republicans. I think Democrats, not Republicans, lost their soul.

Democrats are now the party of baby butchers, socialists, anti-freedom of speech, illegal immigration, anti-traditional family, and pro-sexual perversion.

Republican free-market policies raise everyones standard of living while Democrats socialism leads to more poverty and loss of freedom. Everyone agrees with having a safety net for those overtaken by adversity. But welfare as a way of life is inappropriate and harmful, perpetuating poverty and dependency.

The history of racism belongs to Democrats. The goal of the KKK was overthrow of Republican state governments in the South. The emancipation proclamation was favored by Republicans and opposed by Democrats.The 1964 Civil Rights Act was approved by 80 percent of Republicans and only 60 percent of Democrats.

Voter IDs cost little or nothing and keep no one from voting. People opposed to voter integrity want voter fraud.

Evangelicals voted for Trump as the lesser of two evils. Trump is appointing conservative judges to uphold the Constitution protecting freedom of religion.

I have degrees in physics and nuclear engineering, and an MBA. I like college and science.

The problem is many colleges today indoctrinate the students in Marxist and anti-American ideology while suppressing conservative and Christian speech.

They promote a lot of bad science like evolution, man-made climate change, and use of embryonic stem cells while squelching opposing facts. True science should be open to questioning and alternative ideas.

Please note the Social Security Trust Fund has zero real money because of lying liberals in both parties.

I am disappointed in the Democrats and establishment Republican politicians like Paul Ryan and Mitch McConnell. Trump was voted in to drain the swamp and the swamp creatures are fighting it.

Robert C. Lemke

Joliet

Link:
Letter: Response to 'Disappointed by Republicans' - The Herald-News

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