Category Archives: Stem Cells

Public release date: 27-Jun-2012 [ | E-mail | Share ]

Contact: Clare Ryan clare.ryan@ucl.ac.uk 44-203-108-3846 University College London

Stem cells from patients with a rare form of muscular dystrophy have been successfully transplanted into mice affected by the same form of dystrophy, according to a new study published today in Science Translational Medicine.

For the first time, scientists have turned muscular dystrophy patients' fibroblast cells (common cells found in connective tissue) into stem cells and then differentiated them into muscle precursor cells. The muscle cells were then genetically modified and transplanted into mice.

The new technique, which was initially developed at the San Raffaele Scientific Institute of Milan and completed at UCL, could be used in the future for treating patients with limb-girdle muscular dystrophy (a rare form in which the shoulders and hips are primarily affected) and, possibly, other forms of muscular dystrophies.

Muscular dystrophies are genetic disorders primarily affecting skeletal muscle that result in greatly impaired mobility and, in severe cases, respiratory and cardiac dysfunction. There is no effective treatment, although several new approaches are entering clinical testing including cell therapy.

In this study, scientists focused on genetically modifying a type of cell called a mesoangioblast, which is derived from blood vessels and has been shown in previous studies to have potential in treating muscular dystrophy. However, the authors found that they could not get a sufficient number of mesoangioblasts from patients with limb-girdle muscular dystrophy because the muscles of the patients were depleted of these cells.

Instead, scientists in this study "reprogrammed" adult cells from patients with limb-girdle muscular dystrophy into stem cells and were able to induce them to differentiate into mesoangioblast-like cells. After these 'progenitor' cells were genetically corrected using a viral vector, they were injected into mice with muscular dystrophy, where they homed-in on damaged muscle fibres.

The researchers also showed that when the same muscle progenitor cells were derived from mice the transplanted cells strengthened damaged muscle and enabled the dystrophic mice to run for longer on a treadmill than dystrophic mice that did not receive the cells.

Dr Francesco Saverio Tedesco, UCL Cell & Developmental Biology, who led the study, said: "This is a major proof of concept study. We have shown that we can bypass the limited amount of patients' muscle stem cells using induced pluripotent stem cells and then produce unlimited numbers of genetically corrected progenitor cells.

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Successful transplant of patient-derived stem cells into mice with muscular dystrophy

Public release date: 27-Jun-2012 [ | E-mail | Share ]

Contact: Rolf Kemler kemler@ie-freiburg.mpg.de 49-761-510-8471 Max-Planck-Gesellschaft

This release is available in German.

Scientists at the Max Planck Institute of Immunobiology and Epigenetics in Freiburg have gained important insights for stem cell research which are also applicable to human tumours and could lead to the development of new treatments. As Rolf Kemler's research group discovered, a molecular link exists between the telomerase that determines the length of the telomeres and a signalling pathway known as the Wnt/-signalling pathway.

Telomeres are the end caps of chromosomes that play a very important role in the stability of the genome. Telomeres in stem cells are long and become shorter during differentiation or with age, but lengthen again in tumour cells.

The Wnt/-catenin signalling pathway controls numerous processes in embryonic development, such as the formation of the body axis and of organ primordia, and is particularly active in embryonic and adult stem cells. The -catenin protein plays a key role in this signalling pathway. The incorrect regulation or mutation of -catenin leads to the development of tumours.

Rolf Kemler's research group has now shown that -catenin regulates the telomerase gene directly, and has explained the molecular mechanism at work here. Embryonic stem cells with mutated -catenin generate more telomerase and have extended telomeres, while cells without -catenin have low levels of telomerase and have shortened telomeres.

This regulation mechanism can also be found in human cancer cells. These discoveries could lead to the development of a new approach to the treatment of human tumours.

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Original publication: Wnt/-Catenin Signaling Regulates Telomerase in Stem Cells and Cancer Cells Katrin Hoffmeyer, Angelo Raggioli, Stefan Rudloff, Roman Anton, Andreas Hierholzer, Ignacio Del Valle, Kerstin Hein, Riana Vogt, Rolf Kemler Science 22 June 2012: Vol. 336 no. 6088 pp. 1549-1554 DOI: 10.1126/science.1218370

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Regulation of telomerase in stem cells and cancer cells

Public release date: 27-Jun-2012 [ | E-mail | Share ]

Contact: Bridget Dempsey b.dempsey@qmul.ac.uk 44-207-882-7927 Queen Mary, University of London

Scientists at Queen Mary, University of London have uncovered a link between two genes which shows how stem cells could develop into cancer.

The research, published in the online journal PLoS ONE, found a novel mechanism which could be the catalyst for stem cells changing into a tumour.

Dr Ahmad Waseem, a reader in oral dentistry at Queen Mary, University of London who led the research, said: "It was quite an unexpected discovery. We set out to investigate the role of the stem cell gene Keratin K15 which was thought to be a biomarker for normal stem cells.

"Through our research, we discovered there was link between K15 and the notorious cancer gene FOXM1. We found FOXM1 could target K15 to induce cancer formation."

Cancer develops when there is a problem with stem cells; the cells that carry out internal repairs throughout the human body. The loss of stem cell function leads to uncontrolled growth which ultimately develops into a tumour.

The team went through a process where they used extremely sensitive cell and molecular approaches to establish this link.

The study, funded by the Facial Surgery Research Foundation, Saving Faces, paves the way towards identifying new anti-cancer drugs which could be tailored towards cancer stem cells.

Consultant oral and maxillofacial surgeon Professor Iain Hutchison, founder of Saving Faces and co-author on the study, said: "We are excited about this finding as it could lead to more effective cancer drugs being developed to target cancer stem cells and prevent cancer recurrence."

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Scientists identify new cancer stem cell mechanism

Anda Berada di Sini : Dunia Berita

28 Jun, 2012 10:53 AM

Human Stem Cells Reverse Diabetes In Mice: Research

VANCOUVER, June 28 (Bernama) -- A new research has shown that human stem cell transplants can successfully restore insulin production and reverse diabetes in mice for the first time, China's Xinhua news agency reported.

The study, conducted by scientists from University of British Columbia (UBC) and the New Jersey-based BetaLogics, a division of Janssen Research & Development, LLC, could pave the way for a breakthrough treatment for the disease.

After the stem cell transplant, the diabetic mice were weaned off insulin, a procedure designed to mimic human clinical conditions, according to the study published online Wednesday in the journal Diabetes.

Three to four months later, the mice were able to maintain healthy blood sugar levels even when being fed large quantities of sugar.

"We are very excited by these findings, but additional research is needed before this approach can be tested clinically in humans," said Timothy Kieffer, one of the 13 authors and a professor from UBC.

Kieffer said that the studies were performed in diabetic mice that lacked a properly functioning immune system that would otherwise have rejected the cells.

He added that they now need to identify a suitable way of protecting the cells from immune attack so that the transplant can ultimately be performed in the absence of any immunosuppression.

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Human Stem Cells Reverse Diabetes In Mice: Research

Public release date: 27-Jun-2012 [ | E-mail | Share ]

Contact: Brian Kladko brian.kladko@ubc.ca 604-827-3301 University of British Columbia

University of British Columbia scientists, in collaboration with an industry partner, have successfully reversed diabetes in mice using stem cells, paving the way for a breakthrough treatment for a disease that affects nearly one in four Canadians.

The research by Timothy Kieffer, a professor in the Department of Cellular and Physiological Sciences, and scientists from the New Jersey-based BetaLogics, a division of Janssen Research & Development, LLC, is the first to show that human stem cell transplants can successfully restore insulin production and reverse diabetes in mice. Crucially, they re-created the "feedback loop" that enables insulin levels to automatically rise or fall based on blood glucose levels. The study is published online today in the journal Diabetes.

After the stem cell transplant, the diabetic mice were weaned off insulin, a procedure designed to mimic human clinical conditions. Three to four months later, the mice were able to maintain healthy blood sugar levels even when being fed large quantities of sugar. Transplanted cells removed from the mice after several months had all the markings of normal insulin-producing pancreatic cells.

"We are very excited by these findings, but additional research is needed before this approach can be tested clinically in humans," says Kieffer, a member of UBC's Life Sciences Institute. "The studies were performed in diabetic mice that lacked a properly functioning immune system that would otherwise have rejected the cells. We now need to identify a suitable way of protecting the cells from immune attack so that the transplant can ultimately be performed in the absence of any immunosuppression."

The research was supported by the Canadian Institutes of Health Research, the Stem Cell Network of Canada, Stem Cell Technologies of Vancouver, the JDRF and the Michael Smith Foundation for Health Research.

Diabetes results from insufficient production of insulin by the pancreas. Insulin enables glucose to be stored by the body's muscle, fat and liver and used as fuel; a shortage of insulin leads to high blood sugar that raises the risk of blindness, heart attack, stroke, nerve damage and kidney failure.

Regular injections of insulin are the most common treatment for the type 1 form of this disease, which often strikes young children. Although experimental transplants of healthy pancreatic cells from human donors have shown to be effective, that treatment is severely limited by the availability of donors.

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Stem cells can beat back diabetes: UBC research

The Sugar Land company involved in Gov. Rick Perry's unlicensed adult stem-cell procedure is rife with basic manufacturing problems, according to the U.S. Food and Drug Administration.

In a report one expert called a blow to the entire adult stem-cell industry, the FDA found that Celltex Therapeutics Corp. cannot guarantee the sterility, uniformity and integrity of stem cells it takes from people and then stores and grows for therapeutic reinjection.

You have not performed a validation of your banking and thawing process to assure viability of the stem cells, reads the April 27 report, meaning that the company cannot verify the cells are alive.

The FDA report, which followed an April inspection of Celltex, was released under the Freedom of Information Act on Monday to the Houston Chronicle and a University of Minnesota bioethicist who complained that Celltex is a potential danger to patients and not in compliance with federal law.

The report, partially redacted, was not accompanied by a warning letter.

A former FDA official who asked not to be identified, said the deficiencies 79 in all, from incorrectly labeled products to failed sterility tests are so serious that Celltex risks being shut down if it does not remedy the problems quickly.

Adult stem cells are cells in the body that multiply to replenish dying cells. Long used to treat leukemia and other cancers, they have shown promise for tissue repair in many other diseases in the last decade, although most scientists in the field consider them not ready for mainstream use.

Celltex has been in the public eye since it was revealed that Perry's Houston doctor treated him with his own stem cells during back surgery last July and in follow-up appointments. His stem cells were stored and grown at Celltex.

Perry subsequently called for Texas to become the nation's leader of adult stem-cell medicine, which he touts as an ethical alternative to embryonic stem cells. Perry worked with his Houston doctor and a state representative to write legislation intended to commercialize the therapy in Texas.

In April, the Texas Medical Board approved rules regulating the therapy, which isn't approved by the FDA. The rules allow doctors to use stem cells as long as they get the approval of a review board that evaluates clinical research for safety. The board members were all appointed by Perry.

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FDA critical of stem-cell firm

HOUSTON (AP) - The U.S. Food and Drug Administration has issued a new report criticizing the Texas company that stored adult stem cells from Texas Gov. Rick Perry for use in an experimental procedure for his back pain, according to a newspaper report Monday.

An FDA report obtained by the Houston Chronicle said CellTex Therapeutics cannot guarantee the stem cells it takes from patients remain sterile and alive. The nine-page report dated April 27 says the lab, located in the Houston suburb of Sugar Land, does not have procedures to prevent contamination of products that are supposed to be sterile.

The report also says the lab didnt have written records of investigations into the failure of a batch of cells. It also says the lab has not marked some lab products properly.

The deficiencies identified reflect significant problems, serious issues, said Paul Knoepfler, an associate professor at the University of California-Davis School of Medicine, in an interview with the newspaper. If I were a patient, they would scare me off big time.

CellTex was thrust into the news last year when Perry, then running for the Republican nomination for president, revealed that he had stem cells taken from fat in his body, grown in a lab and then injected into his back during a July operation to address his back pain.

Perrys stem cells were stored and grown at CellTex, the Chronicle reported. The firm is co-owned by Dr. Stanley Jones, Perrys friend who performed the operation.

Subsequently, the Texas Medical Board approved new rules on similar experimental stem cell therapies. Perry appointed the board. The FDA has not approved any adult stem cell therapies for orthopedic use, but experimentation by doctors in the U.S. and abroad is common.

Some scientists tout possible benefits of stem cell treatments, including treatment for heart disease, diabetes and some cancers. Others argue adult stem cell experimentation actually increases the risk of cancer and can cause blood clots.

A Perry spokeswoman called Perrys surgery a success and reaffirmed his commitment to adult stem cell research. She said the FDA report was between the agency and CellTex.

CellTex CEO David Eller said the company invited the FDA inspection, which took place over nearly two weeks in April, according to the report.

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FDA Criticizes Perry’s Stem Cell Lab

Toronto, ON (PRWEB) June 24, 2012

Bel Marra Health, well known for offering high-quality, specially formulated vitamins and nutritional supplements, supports a recent study that shows the effect of stem cells on the newest eye health discovery.

According to a recent medical report published in the journal Molecular Vision, stem cells derived from a human embryo showed the capacity to differentiate into retinal cells, thus serving as a promising resource for eye protection and eye health in potentially blind patients with retinal disorders. The medical report described the results of an experiment that involved the introduction of human embryonic stem cells in the eyes of mice, with the goal of determining whether these cells were capable of growing and transforming into retinal cells. The experiment was conducted in an animal model as an initial test and once positive results were obtained, then it may be possible to conduct similar tests among human subjects.

The study involved injecting stem cells into the retinal space of the eyes of 46 week old mice and maintaining these animals for various periods of time, ranging from three weeks to three months. The eyes of the mice were then excised and histopathologically examined to determine whether these stem cells successfully integrated with the rest of the retina and may possibly help in preventing these animals from becoming blind or for eye protection. The study also investigated whether the original cells of the eyes of the mice generated an immune reaction against the injected stem cells, preventing their capacity in playing a role for eye protection.

The results of the study showed that the stem cells injected into the retinal space of the eyes incorporated well with the rest of the cells of the retina. The eye health of the mice was thus not affected in terms of the presence of these stem cells. In addition, histological examination of the eyes showed that the stem cells transformed into retinal cells, even producing essential proteins that were crucial for eye health and eye protection against becoming blind. However, the study also showed that the stem cells injected into the subretinal region, or the area below the retina, were less prone to integration with the rest of the eye. The results thus showed that stem cells injected into the eye may not be as efficient as first perceived in terms of integration and replacing defective tissues or organs.

Spokesperson for Bel Marra Health Dr. Victor Marchione commented on the study saying, Eye health and eye protection have been prime focus of research efforts in the field of ophthalmology as the incidence of individuals going blind have increased around the world. Different types of eye protection and preventative measures have also been studied to prevent the occurrence of symptoms that may lead to becoming blind. The concept of stem cells has been most appealing in terms of repairing and repairing defective tissues of the body, including its potential for application to eye health and eye protection.

CEO of Bel Marra Health Jim Chiang says more work needs to be done, There is still a need to further examine the specific mechanisms involved in stem cell transformation. The use of stem cells in treating blind people may seem to be too ambitious, yet through intensive years of research, it may still be possible to employ these cells in improving eye health and for eye protection.

(SOURCE: Molecular Vision. Long-term survival and differentiation of retinal neurons derived from human embryonic stem cell lines in un-immunosuppressed mouse retina, April 8, 2012)

Bel Marra Health, the maker of 20/20 Vision Formula, a formulation built in optimal dosages to help maintain healthy body weight, offers quality vitamins and nutritional supplements in formulations designed to address specific health concerns. All ingredients are backed with scientific evidence. Every product is tested for safety, quality, and purity at every stage of the manufacturing process. Furthermore, Bel Marra Health products are produced only in Health Canada approved facilities, going that extra mile to ensure our health conscious customers are getting top quality products. For more information on Bel Marra Health visit http://www.belmarrahealth.com or call 1-866-531-0466.

Bel Marra Health 100-7000 Pine Valley Woodbridge, ON L4L 4Y8 pr(at)belmarrahealth(dot)com 866-531-0466 http://www.belmarrahealth.com

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Bel Marra Health supports a recent study that shows the effect of stem cells on the newest eye health discovery

ScienceDaily (June 24, 2012) The blood-brain barrier -- the filter that governs what can and cannot come into contact with the mammalian brain -- is a marvel of nature. It effectively separates circulating blood from the fluid that bathes the brain, and it keeps out bacteria, viruses and other agents that could damage it.

But the barrier can be disrupted by disease, stroke and multiple sclerosis, for example, and also is a big challenge for medicine, as it can be difficult or impossible to get therapeutic molecules through the barrier to treat neurological disorders.

Now, however, the blood-brain barrier may be poised to give up some of its secrets as researchers at the University of Wisconsin-Madison have created in the laboratory dish the cells that make up the brain's protective barrier. Writing in the June 24, 2012 edition of the journal Nature Biotechnology, the Wisconsin researchers describe transforming stem cells into endothelial cells with blood-brain barrier qualities.

Access to the specialized cells "has the potential to streamline drug discovery for neurological disease," says Eric Shusta, a UW-Madison professor of chemical and biological engineering and one of the senior authors of the new study. "You can look at tens of thousands of drug candidates and just ask the question if they have a chance to get into the brain. There is broad interest from the pharmaceutical industry."

The blood-brain barrier depends on the unique qualities of endothelial cells, the cells that make up the lining of blood vessels. In many parts of the body, the endothelial cells that line capillaries are spaced so that substances can pass through. But in the capillaries that lead to the brain, the endothelial cells nestle in tight formation, creating a semi-permeable barrier that allows some substances -- essential nutrients and metabolites -- access to the brain while keeping others -- pathogens and harmful chemicals -- locked out.

The cells described in the new Wisconsin study, which was led by Ethan S. Lippmann, now a postdoctoral fellow at the Wisconsin Institute for Discovery, and Samira M. Azarin, now a postdoctoral fellow at Northwestern University, exhibit both the active and passive regulatory qualities of those cells that make up the capillaries of the intact brain.

The research team coaxed both embryonic and induced pluripotent stem cells to form the endothelial cells of the blood-brain barrier. The use of induced cells, which can come from patients with specific neurological conditions, may be especially important for modeling disorders that compromise the blood-brain barrier. What's more, because the cells can be mass produced, they could be used to devise high-throughput screens for molecules that may have therapeutic value for neurological conditions or to identify existing drugs that may have neurotoxic qualities.

"The nice thing about deriving endothelial cells from induced pluripotent stem cells is that you can make disease-specific models of brain tissue that incorporate the blood-brain barrier," explains Sean Palecek, a UW-Madison professor of chemical and biological engineering and a senior author of the new report. "The cells you create will carry the genetic information of the condition you want to study."

The generation of the specialized blood-brain barrier endothelial cells, the Wisconsin researchers note, has never been done with stem cells. In addition to the potential applications to screen drugs and model pathologies of the blood-brain barrier, they may also provide a novel window for developmental biologists who are interested in how the barrier comes together and co-develops with the brain.

"Neurons develop at the same time as the endothelial cells," Shusta says, noting that, in development, the cells secrete chemical cues that help determine organ specificity.

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Blood-brain barrier building blocks forged from human stem cells