StemCell Therapy

The death of a woman after she was treated with stem cells at a private clinic in Thailand has reinforced warnings for desperate sick people to avoid stem-cell tourism the gamble of undergoing untested stem-cell treatments in unlicensed private clinics abroad.

Post-mortem results reported this week reveal that the stem-cell treatment almost certainly killed the woman, who had been suffering from kidney disease. She developed strange lumps in the kidney, liver and adrenal gland.

So what are the implications for stem cell research generally, and is it safe for clinical trials to continue? New Scientist has some answers.

What was wrong with the patient, and what treatment did she receive?

She had lupus nephritis, a condition in which the bodys own immune system mistakenly attacks and destroys the kidneys. Usually it can be kept in check with immunosuppressive steroids, but when these failed, the woman turned to a private stem-cell clinic in Bangkok.

How would stem cells help?

Bona-fide trials in European clinics about six years ago showed that some people with similar kidney disease benefited if stem cells from their own bone marrow were injected into their blood. The bodys immune system was first deliberately destroyed with powerful immunosuppressive drugs, then the reinjected stem cells helped to stop the attacks on the kidney by rebuilding and rebalancing the immune system. About a third of the 50 recipients relapsed after a year or so, and 12 of these people died. But around two-thirds saw benefits, with some going into remission.

So what happened with the woman who went to Bangkok?

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Death revives warnings about rogue stem cell clinics - New ...

Dead bodies can provide organs for transplants, now they might become a source of stem cells too. Huge numbers of stem cells can still be mined from bone marrow five days after death to be potentially used in a variety of life-saving treatments.

Human bone marrow contains mesenchymal stem cells, which can develop into bone, cartilage, fat and other cell types. MSCs can be transplanted and the type of cell they form depends on where they are injected. Cells injected into the heart, for example, can form healthy new tissue, a useful therapy for people with chronic heart conditions.

Unlike other tissue transplants, MSCs taken from one person tend not to be rejected by anothers immune system. In fact, MSCs appear to pacify immune cells. It is this feature which has made MSC treatments invaluable for children with graft-versus-host disease, in which transplants aimed at treating diseases such as leukaemia attack the child instead.

Stem cell therapies require a huge numbers of cells though, and it can be difficult to obtain a sufficient amount from a living donor. Could cadavers be the answer? After death, most cells in the body die within a couple of days. But since MSCs live in an environment that is very low in oxygen, Gianluca DIppolito and his colleagues at the University of Miami, Florida, wondered whether they might survive longer than the others.

To investigate, DIppolitos team kept the finger bones of two cadavers for five days. The group then extracted MSCs from the bone marrow of each bone and let them grow in a dish. After five weeks DIppolito was able to transform the stem cells into cartilage, cells that form bone, and fat cells. He presented the results at the World Stem Cell Summit in West Palm Beach, Florida, earlier this month. The team are now trying to get the cells to become nerve and intestinal cells, too.

While only limited amounts of bone marrow can be taken from a living donor, a cadaver represents a plentiful source of cells, says DIppolito. From one donor, you could take the whole spine, for example. You are going to end up with billions of cells.

Paolo Macchiarini, who researches regenerative medicine at the Karolinska Institute in Stockholm, Sweden, describes the work as an excellent advance but says that the cells may not be as healthy as they seem. Their DNA may be affected by the death of surrounding tissue and exposure to cold temperatures. We need to make sure the cells are safe, he says.

Corneal stem cells taken from the eyes of fresh cadavers have already been used to treat blindness in people with eye conditions that result from injury and scarring, but Chris Mason at University College London sees a potential hurdle in using such MSCs in therapy. The work is novel and intriguing but it would be better to use a living donor, he says. Thats partly because medical regulators oppose treating individuals with stem cells from more than one source. You can always go back and get more stem cells from a living donor if you need them, but if you use a cadaver, youll eventually run out.

By Jessica Hamzelou

Originally posted here:
Cadaver stem cells offer new hope of life after death

Diagnosis of brain-stem death

The diagnosis is not technically difficult. In more and more countries, it is made on purely clinical grounds. The aim of the clinical tests is not to probe every neuron within the intracranial cavity to see if it is deadan impossible taskbut to establish irreversible loss of brain-stem function. This is the necessary and sufficient condition for irreversible unconsciousness and irreversible apnea, which together spell a dead patient. Experience has shown that instrumental procedures (such as electroencephalography and studies of cerebral blood flow) that seek to establish widespread loss of cortical function contribute nothing of relevance concerning the cardiac prognosis. Such tests yield answers of dubious reliability to what are widely felt to be the wrong questions. As the concept of brain-stem death is relatively new, most countries rightly insist that the relevant examinations be carried out by physicians of appropriate seniority. These doctors (usually neurologists, anesthetists, or specialists in intensive care) must be entirely separate from any who might be involved in using the patients organs for subsequent transplants.

The diagnosis of brain-stem death involves three stages. First, the cause of the coma must be ascertained, and it must be established that the patient (who will always have been in apneic coma and on a ventilator for several hours) is suffering from irremediable, structural brain damage. Damage is judged irremediable based on its context, the passage of time, and the failure of all attempts to remedy it. Second, all possible causes of reversible brain-stem dysfunction, such as hypothermia, drug intoxication, or severe metabolic upset, must be excluded. Finally, the absence of all brain-stem reflexes must be demonstrated, and the fact that the patient cannot breathe, however strong the stimulus, must be confirmed.

It may take up to 48 hours to establish that the preconditions and exclusions have been met; the testing of brain-stem function takes less than half an hour. When testing the brain-stem reflexes, doctors check for the following normal responses: (1) constriction of the pupils in response to light, (2) blinking in response to stimulation of the cornea, (3) grimacing in response to firm pressure applied just above the eye socket, (4) movements of the eyes in response to the ears being flushed with ice water, and (5) coughing or gagging in response to a suction catheter being passed down the airway. All responses have to be absent on at least two occasions. Apnea, which also must be confirmed twice, is assessed by disconnecting the patient from the ventilator. (Prior to this test, the patient is fully oxygenated by being made to breathe 100 percent oxygen for several minutes, and diffusion oxygenation into the trachea is maintained throughout the procedure. These precautions ensure that the patient will not suffer serious oxygen deprivation while disconnected from the ventilator.) The purpose of this test is to establish the total absence of any inspiratory effort as the carbon dioxide concentration in the blood (the normal stimulus to breathing) reaches levels more than sufficient to drive any respiratory centre cells that may still be alive.

The patient thus passes through a tight double filter of preconditions and exclusions before he is even tested for the presence of a dead brain stem. This emphasis on strict preconditions and exclusions has been a major contribution to the subject of brain-stem death, and it has obviated the need for ancillary investigations. Thousands of patients who have met criteria of this kind have had ventilation maintained: all have developed asystole within a few hours or a few days, and none has ever regained consciousness. There have been no exceptions. The relevant tests for brain-stem death are carried out systematically and without haste. There is no pressure from the transplant team.

The developments in the idea and diagnosis of brain-stem death came as a response to a conceptual challenge. Intensive-care technology had saved many lives, but it had also created many brain-dead patients. To grasp the implications of this situation, society in generaland the medical profession in particularwas forced to rethink accepted notions about death itself. The emphasis had to shift from the most common mechanism of death (i.e., irreversible cessation of the circulation) to the results that ensued when that mechanism came into operation: irreversible loss of the capacity for consciousness, combined with irreversible apnea. These results, which can also be produced by primary intracranial catastrophes, provide philosophically sound, ethically acceptable, and clinically applicable secular equivalents to the concepts of departure of the soul and loss of the breath of life, which were so important to some earlier cultures.

Throughout history, specific cultural contexts have always played a crucial role in how people perceived death. Different societies have held widely diverging views on the breath of life and on how the soul left the body at the time of death. Such ideas are worth reviewing (1) because of the light they throw on important residual elements of popular belief; (2) because they illustrate the distance traveled (or not traveled) between early beliefs and current ones; and (3) because of the relevance of certain old ideas to contemporary debates about brain-stem death and about the philosophical legitimacy of organ transplantation. The following discussion therefore focuses on how certain cultural ideas about death compare or contrast with the modern concept. For an overview of various eschatologies from a cross-cultural perspective, see death rite: Death rites and customs.

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death :: Diagnosis of brain-stem death | Britannica.com

Programmed cell-death (or PCD) is death of a cell in any form, mediated by an intracellular program.[1][2] PCD is carried out in a regulated process, which usually confers advantage during an organism's life-cycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate. PCD serves fundamental functions during both plant and metazoa (multicellular animals) tissue development. Apoptosis and autophagy are both forms of programmed cell death, but necrosis is a non-physiological process that occurs as a result of infection or injury.[3]

Necrosis is the death of a cell caused by external factors such as trauma or infection and occurs in several different forms. Recently a form of programmed necrosis, called necroptosis, has been recognized as an alternate form of programmed cell death. It is hypothesized that necroptosis can serve as a cell-death backup to apoptosis when the apoptosis signaling is blocked by endogenous or exogenous factors such as viruses or mutations.

The concept of "programmed cell-death" was used by Lockshin & Williams[4] in 1964 in relation to insect tissue development, around eight years before "apoptosis" was coined. Since then, PCD has become the more general of these two terms.

The first insight into the mechanism came from studying BCL2, the product of a putative oncogene activated by chromosome translocations often found in follicular lymphoma. Unlike other cancer genes, which promote cancer by stimulating cell proliferation, BCL2 promoted cancer by stopping lymphoma cells from being able to kill themselves.[5]

PCD has been the subject of increasing attention and research efforts. This trend has been highlighted with the award of the 2002 Nobel Prize in Physiology or Medicine to Sydney Brenner (United Kingdom), H. Robert Horvitz (US) and John E. Sulston (UK).[6]

Apoptosis is the process of programmed cell death (PCD) that may occur in multicellular organisms.[8]Biochemical events lead to characteristic cell changes (morphology) and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation. It is now thought that- in a developmental context- cells are induced to positively commit suicide whilst in a homeostatic context; the absence of certain survival factors may provide the impetus for suicide. There appears to be some variation in the morphology and indeed the biochemistry of these suicide pathways; some treading the path of "apoptosis", others following a more generalized pathway to deletion, but both usually being genetically and synthetically motivated. There is some evidence that certain symptoms of "apoptosis" such as endonuclease activation can be spuriously induced without engaging a genetic cascade, however, presumably true apoptosis and programmed cell death must be genetically mediated. It is also becoming clear that mitosis and apoptosis are toggled or linked in some way and that the balance achieved depends on signals received from appropriate growth or survival factors.[9]

Macroautophagy, often referred to as autophagy, is a catabolic process that results in the autophagosomic-lysosomal degradation of bulk cytoplasmic contents, abnormal protein aggregates, and excess or damaged organelles.

Autophagy is generally activated by conditions of nutrient deprivation but has also been associated with physiological as well as pathological processes such as development, differentiation, neurodegenerative diseases, stress, infection and cancer.

A critical regulator of autophagy induction is the kinase mTOR, which when activated, suppresses autophagy and when not activated promotes it. Three related serine/threonine kinases, UNC-51-like kinase -1, -2, and -3 (ULK1, ULK2, UKL3), which play a similar role as the yeast Atg1, act downstream of the mTOR complex. ULK1 and ULK2 form a large complex with the mammalian homolog of an autophagy-related (Atg) gene product (mAtg13) and the scaffold protein FIP200. Class III PI3K complex, containing hVps34, Beclin-1, p150 and Atg14-like protein or ultraviolet irradiation resistance-associated gene (UVRAG), is required for the induction of autophagy.

The ATG genes control the autophagosome formation through ATG12-ATG5 and LC3-II (ATG8-II) complexes. ATG12 is conjugated to ATG5 in a ubiquitin-like reaction that requires ATG7 and ATG10. The Atg12Atg5 conjugate then interacts non-covalently with ATG16 to form a large complex. LC3/ATG8 is cleaved at its C terminus by ATG4 protease to generate the cytosolic LC3-I. LC3-I is conjugated to phosphatidylethanolamine (PE) also in a ubiquitin-like reaction that requires Atg7 and Atg3. The lipidated form of LC3, known as LC3-II, is attached to the autophagosome membrane.

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Programmed cell death - Wikipedia, the free encyclopedia

Introduction: What are stem cells, and why are they important? What are the unique properties of all stem cells? What are embryonic stem cells? What are adult stem cells? What are the similarities and differences between embryonic and adult stem cells? What are induced pluripotent stem cells? What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized? Where can I get more information? VII. What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?

There are many ways in which human stem cells can be used in research and the clinic. Studies of human embryonic stem cells will yield information about the complex events that occur during human development. A primary goal of this work is to identify how undifferentiated stem cells become the differentiated cells that form the tissues and organs. Scientists know that turning genes on and off is central to this process. Some of the most serious medical conditions, such as cancer and birth defects, are due to abnormal cell division and differentiation. A more complete understanding of the genetic and molecular controls of these processes may yield information about how such diseases arise and suggest new strategies for therapy. Predictably controlling cell proliferation and differentiation requires additional basic research on the molecular and genetic signals that regulate cell division and specialization. While recent developments with iPS cells suggest some of the specific factors that may be involved, techniques must be devised to introduce these factors safely into the cells and control the processes that are induced by these factors.

Human stem cells are currently being used to test new drugs. New medications are tested for safety on differentiated cells generated from human pluripotent cell lines. Other kinds of cell lines have a long history of being used in this way. Cancer cell lines, for example, are used to screen potential anti-tumor drugs. The availability of pluripotent stem cells would allow drug testing in a wider range of cell types. However, to screen drugs effectively, the conditions must be identical when comparing different drugs. Therefore, scientists must be able to precisely control the differentiation of stem cells into the specific cell type on which drugs will be tested. For some cell types and tissues, current knowledge of the signals controlling differentiation falls short of being able to mimic these conditions precisely to generate pure populations of differentiated cells for each drug being tested.

Perhaps the most important potential application of human stem cells is the generation of cells and tissues that could be used for cell-based therapies. Today, donated organs and tissues are often used to replace ailing or destroyed tissue, but the need for transplantable tissues and organs far outweighs the available supply. Stem cells, directed to differentiate into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat diseases including maculardegeneration, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis.

Figure 3. Strategies to repair heart muscle with adult stem cells. Click here for larger image.

2008 Terese Winslow

For example, it may become possible to generate healthy heart muscle cells in the laboratory and then transplant those cells into patients with chronic heart disease. Preliminary research in mice and other animals indicates that bone marrow stromal cells, transplanted into a damaged heart, can have beneficial effects. Whether these cells can generate heart muscle cells or stimulate the growth of new blood vessels that repopulate the heart tissue, or help via some other mechanism is actively under investigation. For example, injected cells may accomplish repair by secreting growth factors, rather than actually incorporating into the heart. Promising results from animal studies have served as the basis for a small number of exploratory studies in humans (for discussion, see call-out box, "Can Stem Cells Mend a Broken Heart?"). Other recent studies in cell culture systems indicate that it may be possible to direct the differentiation of embryonic stem cells or adult bone marrow cells into heart muscle cells (Figure 3).

Cardiovascular disease (CVD), which includes hypertension, coronary heart disease, stroke, and congestive heart failure, has ranked as the number one cause of death in the United States every year since 1900 except 1918, when the nation struggled with an influenza epidemic. Nearly 2,600 Americans die of CVD each day, roughly one person every 34 seconds. Given the aging of the population and the relatively dramatic recent increases in the prevalence of cardiovascular risk factors such as obesity and type 2 diabetes, CVD will be a significant health concern well into the 21st century.

Cardiovascular disease can deprive heart tissue of oxygen, thereby killing cardiac muscle cells (cardiomyocytes). This loss triggers a cascade of detrimental events, including formation of scar tissue, an overload of blood flow and pressure capacity, the overstretching of viable cardiac cells attempting to sustain cardiac output, leading to heart failure, and eventual death. Restoring damaged heart muscle tissue, through repair or regeneration, is therefore a potentially new strategy to treat heart failure.

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What are the potential uses of human stem cells and the ...

Proc Natl Acad Sci U S A. 2008 September 30; 105(39): 1503415039.

Medical Sciences

*Vaccine and Infectious Disease Institute and

Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;

BioMaPS Institute for Quantitative Biology, Rutgers University, New Brunswick, NJ 08901;

Departments of Therapeutic Radiology, Genetics, and Dermatology and Yale Comprehensive Cancer Center, Yale School of Medicine, New Haven, CT 06520; and

Molecular and Cellular Oncogenesis Program, Wistar Institute, Philadelphia, PA 19104

Edited by Stanley M. Gartler, University of Washington, Seattle, WA, and approved July 24, 2008

Author contributions: D.L.C., J.T.E., D.E.B., C.C.M., and E.G.L. designed research; D.L.C. and D.E.B. performed research; D.L.C. and J.T.E. contributed new reagents/analytic tools; D.L.C. and E.G.L. analyzed data; and D.L.C., D.E.B., C.C.M., and E.G.L. wrote the paper.

Clonal expansion of premalignant lesions is an important step in the progression to cancer. This process is commonly considered to be a consequence of sustaining a proliferative mutation. Here, we investigate whether the growth trajectory of clones can be better described by a model in which clone growth does not depend on a proliferative advantage. We developed a simple computer model of clonal expansion in an epithelium in which mutant clones can only colonize space left unoccupied by the death of adjacent normal stem cells. In this model, competition for space occurs along the frontier between mutant and normal territories, and both the shapes and the growth rates of lesions are governed by the differences between mutant and normal cells' replication or apoptosis rates. The behavior of this model of clonal expansion along a mutant clone's frontier, when apoptosis of both normal and mutant cells is included, matches the growth of UVB-induced p53-mutant clones in mouse dorsal epidermis better than a standard exponential growth model that does not include tissue architecture. The model predicts precancer cell mutation and death rates that agree with biological observations. These results support the hypothesis that clonal expansion of premalignant lesions can be driven by agents, such as ionizing or nonionizing radiation, that cause cell killing but do not directly stimulate cell replication.

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Preneoplastic lesion growth driven by the death of ...

In 1968, doctors performed the first successful bone marrow transplant. Bone marrow contains somatic stem cells that can produce all of the different cell types that make up our blood. It is transplanted routinely to treat a variety of blood and bone marrow diseases, blood cancers, and immune disorders. More recently, stem cells from the blood stream (called peripheral blood stem cells) and umbilical cord stem cells have been used to treat some of the same blood-based diseases.

Leukemia is a cancer of white blood cells, or leukocytes. Like other blood cells, leukocytes develop from somatic stem cells. Mature leukocytes are released into the bloodstream, where they work to fight off infections in our bodies.

Leukemia results when leukocytes begin to grow and function abnormally, becoming cancerous. These abnormal cells cannot fight off infection, and they interfere with the functions of other organs.

Successful treatment for leukemia depends on getting rid of all the abnormal leukocytes in the patient, allowing healthy ones to grow in their place. One way to do this is through chemotherapy, which uses potent drugs to target and kill the abnormal cells. When chemotherapy alone can't eliminate them all, physicians sometimes turn to bone marrow transplants.

In a bone marrow transplant, the patient's bone marrow stem cells are replaced with those from a healthy, matching donor. To do this, all of the patient's existing bone marrow and abnormal leukocytes are first killed using a combination of chemotherapy and radiation. Next, a sample of donor bone marrow containing healthy stem cells is introduced into the patient's bloodstream.

If the transplant is successful, the stem cells will migrate into the patient's bone marrow and begin producing new, healthy leukocytes to replace the abnormal cells.

New evidence suggests that bone marrow stem cells may be able to differentiate into cell types that make up tissues outside of the blood, such as liver and muscle. Scientists are exploring new uses for these stem cells that go beyond diseases of the blood.

While most blood stem cells reside in the bone marrow, a small number are present in the bloodstream. These peripheral blood stem cells, or PBSCs, can be used just like bone marrow stem cells to treat leukemia, other cancers and various blood disorders.

Since they can be obtained from drawn blood, PBSCs are easier to collect than bone marrow stem cells, which must be extracted from within bones. This makes PBSCs a less invasive treatment option than bone marrow stem cells. PBSCs are sparse in the bloodstream, however, so collecting enough to perform a transplant can pose a challenge.

Newborn infants no longer need their umbilical cords, so they have traditionally been discarded as a by-product of the birth process. In recent years, however, the stem-cellrich blood found in the umbilical cord has proven useful in treating the same types of health problems as those treated using bone marrow stem cells and PBSCs.

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Stem Cells In Use - Learn Genetics

AUTOLOGOUS Adipose Stem Cells

Stem Cell Therapy is not a new technology. As a matter of fact it has been around for more that 60 years now. The problem is most people know it as a bone marrow transplant. And well when you finish saying that people are already screaming "That's Painful". A bone marrow transplant essentially extracts stem cells from your own bone marrow and then returns them back to you. It has been used to help people suffering from conditions like Leukemia and Lymph Node Cancer.

How does it work? Stem Cells hone in on "chemokine" signals that are secreted by injury. When they arrive they alert regenerative cells to go to work and repair the damage, or grow tissue.

At birth, the human body has around 80 million active stem cells working. At age 40 we have less than 25 million active stem cells working. Therefore it takes longer for the body to heal and in some cases damage is often ignored. This is the aging or degeneration process of the body.

In 1998 a little known about Bio Tech Company discovered that there was an enormous amount of stem cells in abdominal fat, commonly referred to as Adipose fat. In fact there are about 1-2 million stem cells and regenerative cells in 1 cc of abdominal fat. Bone marrow contains less than 10% of that. The stem cells in the abdomen are in a dormant or inactive state. The challenge lay only in how to activate them.

In early 2000 the problem had been solved. A special separation process was used to isolate stem cells from abdominal fat and a perfected heliotherapy process activated the stem cells. These super-charged stem cells were now ready to go to work healing your body.

Fat Stem Cell Therapy has been used for over a decade now as therapy for a variety of medical problems as well as an alternative to painful cosmetic surgery. Fat Stem Cell Therapy can help patients suffering from medical conditions such as, Osteoarthritis, Pulmonary Disease, and Diabetes Type II, as well as some Cosmetic Procedures like Face Lifts, Breast Augmentation, and Anti-Aging.

Infinite Horizons Medical Center and its association with a leading Bio Tech company are able to deliver these high tech therapies with precision, expertise and a level of care which rivals any in the world. These painless medical procedures uses the clients' own adult stem cells to treat clients' medical problems. The procedures themselves take roughly 3.5 - 7 hours to complete.

The procedure involves extracting autologous adipose stem cells, enriching them, activating the enriched stem cells and finally returning these stem cells back into the clients' body. The procedure only requires a local anesthetic, is 100% safe, 100% effective and there is a 0% chance of rejection. For more detailed information see our procedure page.

Infinite Horizons Medical Center has put together an incredible program for clients in search of medical treatment with fat stem cell therapy for, Pulmonary Disorders, like IPF or COPD, Diabetes Type II and Osteoarthritis. It has also put together special programs with fat stem cell therapy for cosmetic procedures like Anti-Aging, Breast Augmentation and Face Lifts.

Link:
Fat Stem Cell Therapy

Stem cells are a special form of human life: they are alive and contain human DNA. They have a unique feature in that they can be coaxed into developing into some or all of the 220 cell types found in the human body. Eventually, stem cells may be routinely used by doctors to generate new organs or new replacement body parts for people: They might become a new pancreas to cure a person with diabetes, or new nerve cells to cure a paralized person, etc.

There are three types of stem cells:

"...reprogrammed a dozen cell types, including those from the brain, skin, lung and liver, hinting that the method will work with most, if not all, cell types. On average, she says, 25% of the cells survive the stress and 30% of those convert to pluripotent cells already a higher proportion than the roughly 1% conversion rate of iPS cells." 1

Sponsored link.

The National Institutes of Health web site states:

"To realize the promise of novel cell-based therapies for such pervasive and debilitating diseases, scientists must be able to manipulate stem cells so that they possess the necessary characteristics for successful differentiation, transplantation, and engraftment. The following is a list of steps in successful cell-based treatments that scientists will have to learn to control to bring such treatments to the clinic. To be useful for transplant purposes, stem cells must be reproducibly made to:

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Human stem cell research: all viewpoints - Religious tolerance

Inside the microscopic world of the mouse hair follicle, Yale Cancer Center researchers have discovered big clues about how stem cells regenerate and die. These findings, published April 6 in the journal Nature, could lead to a better understanding of how the stem cell pool is maintained or altered in tissues throughout the body.

Stem cells are undifferentiated cells that replenish themselves and, based on their tissue location, can become specialized cells such as blood or skin cells. The hair follicle is an ideal site for exploring stem cell behavior because it has distinct and predictable oscillations in the number and behavior of stem cells, said the studys lead author, Kailin R. Mesa, a third-year doctoral student in the lab of Valentina Greco, associate professor of genetics, cell biology, and dermatology.

Using live microscopic imaging to track stem cell behavior in the skin of living mice, researchers observed that the stem cell niche, or surrounding area, plays a critical role in whether stem cells grow or die.

Prior to this, it wasnt clear whether stem cell regulation was intrinsic or extrinsic, and now we know it is external in that the niche instructs the stem cells, Mesa said. In terms of cancer, we can next explore how we might perturb or change the niche in hopes of affecting the growth of cancer stem cells.

Also, researchers were surprised to find that the stem cells within the pool fed on other dying stem cells. This reveals a mechanism for removing dead cells, a process previously observed in mammary glands but never in the skin.

This study was supported by the Yale Dermatology Spore, National Institutes of Health, American Cancer Society, and New York Stem Cell Foundation.

Citation: Nature

(Photo via Shutterstock)

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YaleNews | Research in the News: Tiny hair follicle offers ...

By Charles Choi, LiveScience contributor

Death will come for us all one day, but life will not fade from our bodies all at once. After our lungs stop breathing, our hearts stop beating, our minds stop racing, our bodies cool, and long after our vital signs cease, little pockets of cells can live for days, even weeks. Now scientists have harvested such cells from the scalps and brain linings of human corpses and reprogrammed them into stem cells.

In other words, dead people can yield living cells that can be converted into any cell or tissue in the body.

As such, this work could help lead to novel stem cell therapies and shed light on a variety of mental disorders, such as schizophrenia, autism and bipolar disorder, which may stem from problems with development, researchers say.

Making stem cells Mature cells can be made or induced to become immature cells, known as pluripotent stem cells, which have the ability to become any tissue in the body and potentially can replace cells destroyed by disease or injury. This discovery was honored last week with the Nobel Prize.

Past research showed this same process could be carried out with so-called fibroblasts taken from the skin of human cadavers. Fibroblasts are the most common cells of connective tissue in animals, and they synthesize the extracellular matrix, the complex scaffolding between cells. [ Science of Death: 10 Tales from the Crypt ]

Cadaver-collected fibroblasts can be reprogrammed into induced pluripotent stem cells using chemicals known as growth factors that are linked with stem cell activity. Reprogrammed cells could then develop into a multitude of cell types, including the neurons found in the brain and spinal cord. However, bacteria and fungi on the skin can wreak havoc on the culturing processes used to grow cells in labs, making the process tricky to successfully carry out.

Now scientists have taken fibroblasts from the scalps and the brain linings of 146 human brain donors and grown induced pluripotent stem cells from them as well.

"We were able to culture living cells from deceased individuals on a larger scale than ever done before," researcher Thomas Hyde, a neuroscientist, neurologist and chief operating officer at the Lieber Institute for Brain Development in Baltimore, told LiveScience. Previous studies had only grown fibroblasts from a total of about a half-dozen cadavers.

The bodies had been dead up to nearly two days before scientists collected tissues from them. The corpses had been kept cool in the morgue, but not frozen.

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New life for the dead: Stem cells from corpse scalp

Death will come for us all one day, but life will not fade from our bodies all at once. After our lungs stop breathing, our hearts stop beating, our minds stop racing, our bodies cool, and long after our vital signs cease, little pockets of cells can live for days, even weeks. Now scientists have harvested such cells from the scalps and brain linings of human corpses and reprogrammed them into stem cells.

In other words, dead people can yield living cells that can be converted into any cell or tissue in the body.

As such, this work could help lead to novel stem cell therapies and shed light on a variety of mental disorders, such as schizophrenia, autism and bipolar disorder, which may stem from problems with development, researchers say.

Making stem cells

Mature cells can be made or induced to become immature cells, known as pluripotent stem cells, which have the ability to become any tissue in the body and potentially can replace cells destroyed by disease or injury. This discovery was honored last week with the Nobel Prize.

Past research showed this same process could be carried out with so-called fibroblasts taken from the skin of human cadavers. Fibroblasts are the most common cells of connective tissue in animals, and they synthesize the extracellular matrix, the complex scaffolding between cells. [Science of Death: 10 Tales from the Crypt]

Cadaver-collected fibroblasts can be reprogrammed into induced pluripotent stem cells using chemicals known as growth factors that are linked with stem cell activity. Reprogrammed cells could then develop into a multitude of cell types, including the neurons found in the brain and spinal cord. However, bacteria and fungi on the skin can wreak havoc on the culturing processes used to grow cells in labs, making the process tricky to successfully carry out.

Now scientists have taken fibroblasts from the scalps and the brain linings of 146 human brain donors and grown induced pluripotent stem cells from them as well.

"We were able to culture living cells from deceased individuals on a larger scale than ever done before," researcher Thomas Hyde, a neuroscientist, neurologist and chief operating officer at the Lieber Institute for Brain Development in Baltimore, told LiveScience. Previous studies had only grown fibroblasts from a total of about a half-dozen cadavers.

The bodies had been dead up to nearly two days before scientists collected tissues from them. The corpses had been kept cool in the morgue, but not frozen.

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Human Cadaver Brains May Provide New Stem Cells

By Emily Underwood, ScienceNOW

Four young boys with a rare, fatal brain condition have made it through a dangerous ordeal. Scientists have safely transplanted human neural stem cells into their brains. Twelve months after the surgeries, the boys have more myelin a fatty insulating protein that coats nerve fibers and speeds up electric signals between neurons and show improved brain function, a new study in Science Translational Medicine reports. The preliminary trial paves the way for future research into potential stem cell treatments for the disorder, which overlaps with more common diseases such as Parkinsons disease and multiple sclerosis.

This is very exciting, says Douglas Fields, a neuroscientist at the National Institutes of Health in Bethesda, Maryland, who was not involved in the work. From these early studies one sees the promise of cell transplant therapy in overcoming disease and relieving suffering.

Without myelin, electrical impulses traveling along nerve fibers in the brain cant travel from neuron to neuron says Nalin Gupta, lead author of the study and a neurosurgeon at the University of California, San Francisco (UCSF). Signals in the brain become scattered and disorganized, he says, comparing them to a pile of lumber. You wouldnt expect lumber to assemble itself into a house, he notes, yet neurons in a newborn babys brain perform a similar feat with the help of myelin-producing cells called oligodendrocytes. Most infants are born with very little myelin and develop it over time. In children with early-onset Pelizaeus-Merzbacher disease, he says, a genetic mutation prevents oligodendrocytes from producing myelin, causing electrical signals to die out before they reach their destinations. This results in serious developmental setbacks, such as the inability to talk, walk, or breathe independently, and ultimately causes premature death.

Although researchers have long dreamed of implanting human neural stem cells to generate healthy oligodendrocytes and replace myelin, it has taken years of research in animals to develop a stem cell that can do the job, says Stephen Huhn, vice president of Newark, California-based StemCells Inc., the biotechnology company that created the cells used in the study and that funded the research. However, he says, a separate study by researchers at Oregon Health & Science University, Portland, found that the StemCell Inc. cells specialized into oligodendrocytes 60 percent to 70 percent of the time in mice, producing myelin and improved survival rates in myelin-deficient animals. So the team was able to test the cells safety and efficacy in the boys.

Led by Gupta, the researchers drilled four small holes in each childs skull and then used a fine needle to insert millions of stem cells into white matter deep in their frontal lobes. The scientists administered a drug that suppressed the boys immune systems for 9 months to keep them from rejecting the cells and checked their progress with magnetic resonance imaging and a variety of psychological and motor tests. After a year, each of the boys showed brain changes consistent with increased myelination and no serious side effects such as tumors, says David Rowitch, one of the neuroscientists on the UCSF team. In addition, three of the four boys showed modest improvements in their development. For example, the 5-year-old boy the oldest child in the study had begun for the first time to feed himself and walk with minimal assistance.

Although these signs are encouraging, Gupta and Rowitch say, a cure for Pelizaeus-Merzbacher disease is not near. Animal studies strongly support the idea that the stem cells are producing myelin-making oligodendrocytes in the boys, but its possible that the myelination didnt result from the transplant but from a bout of normal growth. Rowitch adds that although such behavioral improvements are unusual for the disease, they could be a fluke. Huhn acknowledges that the study is small and has no control, but hes is still excited. We are for the first time seeing a biological effect of a neural stem cells transplantation into the brain [in humans]. The most important thing, he says, is that the transplants appear safe. This gives the researchers a green light to pursue larger, controlled studies, he says.

It isnt the flashiest thing, but demonstrating that its feasible to transplant these stem cells into childrens brains without negative consequences at least so far is extremely hopeful, says Timothy Kennedy, a neuroscientist at McGill University in Montreal, Canada.

Although hes concerned that myelination seen in mouse models might not scale up to a disease as severe as Pelizaeus-Merzbacher in humans, Ian Duncan, a neuroscientist at the University of Wisconsin, Madison, describes the study as setting a precedent for translating animal research in stem cells to humans. If you could improve quality of life by targeting key areas of the brain with these cells, he says, that would be a huge advance.

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Stem Cells Show Early Promise for Rare Brain Disorder

SAN FRANCISCO A Phase I clinical trial led by investigators from the University of California, San Francisco and sponsored by Stem Cells Inc., showed that neural stem cells successfully engrafted into the brains of patients and appear to have produced myelin.

The study, published in today's (Oct. 10) issue of Science Translational Medicine, also demonstrated that the neural stem cells were safe in the patients' brains one year post transplant.

The results of the investigation, designed to test safety and preliminary efficacy, are encouraging, said principal investigator David H. Rowitch, M.D., Ph.D., a professor of pediatrics and neurological surgery at UCSF, chief of neonatology at UCSF Benioff Children's Hospital and a Howard Hughes Medical Institute Investigator.

"For the first time, we have evidence that transplanted neural stem cells are able to produce new myelin in patients with a severe myelination disease," said Nalin Gupta, M.D., Ph.D., associate professor of neurological surgery and pediatrics and chief of pediatric neurological surgery at UCSF Benioff Children's Hospital, and co-principal investigator of the PMD clinical trial.

"We also saw modest gains in neurological function, and while these can't necessarily be attributed to the intervention because this was an uncontrolled trial with a small number of patients, the findings represent an important first step that strongly supports further testing of this approach as a means to treat the fundamental pathology in the brain of these patients."

In the trial, human neural stem cells developed by StemCells, Inc., of Newark, Calif., were injected directly into the brains of four young children with an early-onset, fatal form of a condition known as Pelizaeus-Merzbacher disease (PMD).

In PMD, an inherited genetic defect prevents brain cells called oligodendrocytes from making myelin, a fatty material that insulates white matter which serves as a conduit for nervous impulses throughout the brain. Without myelin sheathing, white matter tracts short-circuit like bare electrical wires and are unable to correctly propagate nerve signals, resulting in neurological dysfunction and neurodegeneration. Patients with early-onset PMD cannot walk or talk, often have trouble breathing and undergo progressive neurological deterioration leading to death between ages 10 and 15. The disease usually occurs in males.

Multiple sclerosis and certain forms of cerebral palsy also involve damage to oligodendrocytes and subsequent demyelination.

Before and after the transplant procedures in the children with PMD, which were conducted between 2010-11, the patients were given standard neurological examinations and developmental assessments, and underwent magnetic resonance imaging (MRI). "MRI is the most stringent non-invasive method we have of assessing myelin formation," said Rowitch.

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Trial: Transplanted neural stem cells produced myelin

Phase I Investigation Demonstrates Signs of Engraftment and Safety at One Year

Newswise A Phase I clinical trial led by investigators from the University of California, San Francisco and sponsored by Stem Cells Inc., showed that neural stem cells successfully engrafted into the brains of patients and appear to have produced myelin.

The study, published in the Oct. 10, 2012 issue of Science Translational Medicine, also demonstrated that the neural stem cells were safe in the patients brains one year post transplant.

The results of the investigation, designed to test safety and preliminary efficacy, are encouraging, said principal investigator David H. Rowitch, MD, PhD, a professor of pediatrics and neurological surgery at UCSF, chief of neonatology at UCSF Benioff Childrens Hospital and a Howard Hughes Medical Institute Investigator.

For the first time, we have evidence that transplanted neural stem cells are able to produce new myelin in patients with a severe myelination disease, said Nalin Gupta, MD, PhD, associate professor of neurological surgery and pediatrics and chief of pediatric neurological surgery at UCSF Benioff Children's Hospital, and co-principal investigator of the PMD clinical trial.

We also saw modestgains in neurological function, and while these cant necessarily be attributed to the intervention because this was an uncontrolled trial with a small number of patients,the findings represent an important first step that strongly supports further testing of this approach as a means to treat the fundamental pathology in the brain of these patients.

In the trial, human neural stem cells developed by StemCells, Inc., of Newark, California, were injected directly into the brains of four young children with an early-onset, fatal form of a condition known as Pelizaeus-Merzbacher disease (PMD).

In PMD, an inherited genetic defect prevents brain cells called oligodendrocytes from making myelin, a fatty material that insulates white matter which serves as a conduit for nervous impulses throughout the brain. Without myelin sheathing, white matter tracts short-circuit like bare electrical wires and are unable to correctly propagate nerve signals, resulting in neurological dysfunction and neurodegeneration. Patients with early-onset PMD cannot walk or talk, often have trouble breathing and undergo progressive neurological deterioration leading to death between ages 10 and 15.The disease usually occurs in males.

Multiple sclerosis and certain forms of cerebral palsy also involve damage to oligodendrocytes and subsequent demyelination.

Before and after the transplant procedures in the children with PMD, which were conducted between 2010-2011, the patients were given standard neurological examinations and developmental assessments, and underwent magnetic resonance imaging (MRI). MRI is the most stringent non-invasive method we have of assessing myelin formation, said Rowitch. The investigators found evidence that the stem cells had successfully engrafted, receiving blood and nutrients from the surrounding tissue and integrating into the brain, a process that Rowitch likened to a plant taking root.

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Study Shows Evidence that Transplanted Neural Stem Cells Produced Myelin

NEWARK, Calif., Oct. 10, 2012 (GLOBE NEWSWIRE) -- StemCells, Inc. (STEM) today announced that two papers reporting clinical and preclinical data demonstrating the therapeutic potential of the Company's proprietary HuCNS-SC(R) cells (purified human neural stem cells) for a range of myelination disorders were published in the Oct. 10 edition of Science Translational Medicine, the peer review journal of the American Association for the Advancement of Science (http://stm.sciencemag.org/).

The paper by Gupta, et al. describes the encouraging results of the Company's Phase I clinical trial in Pelizaeus-Merzbacher disease (PMD), a genetic myelination disorder that afflicts children. In the trial, which was completed in February 2012, four patients were transplanted with the Company's HuCNS-SC cells and all showed preliminary evidence of progressive and durable donor cell-derived myelination. Three of the four patients showed modest gains in their neurological function, which suggests a departure from the natural history of the disease; the fourth patient remained stable. Although clinical benefit cannot be confirmed in a trial without control patients, the small but measureable gains in function at one year may represent signals of a clinical effect to be further investigated in a controlled trial with more patients.

The second of the two papers, by Uchida, et al., summarizes extensive preclinical research which demonstrated that transplantation of the Company's neural stem cells in an animal model of severe myelin deficiency results in new myelin which enhanced the conductivity of nerve impulses. Myelin is the substance that insulates nerve axons, and without sufficient myelination, nerve impulses are not properly transmitted and neurological function is impaired. This preclinical data provided the rationale for the PMD clinical trial and supports the Company's cell therapy approach to other myelination disorders, such as transverse myelitis, certain forms of cerebral palsy, and multiple sclerosis.

"For the first time, we have evidence that transplanted neural stem cells are able to produce new myelin in patients with a severe myelination disease," Nalin Gupta, MD, PhD, associate professor of neurological surgery and pediatrics and chief of pediatric neurological surgery at UCSF Benioff Children's Hospital, and co-principal investigator of the PMD clinical trial. "We also saw modest gains in neurological function, and while these can't necessarily be attributed to the intervention because this was an uncontrolled trial with a small number of patients, it is an important first step which provides hope that HuCNS-SC transplantation may be able to address the fundamental pathology in the brain of PMD patients."

Patients with PMD have a defective gene which leads to insufficient myelin in the brain, which leads to a progressive loss of neurological function and death. In the clinical trial, four patients with connatal PMD, the most severe form of the disease, were enrolled and transplanted with HuCNS-SC cells. The patients were followed for twelve months after transplantation, during which time they underwent intensive neurological assessments and magnetic resonance (MR) imaging at regular intervals. The findings from the trial indicate a favorable safety profile for the HuCNS-SC cells and the transplantation procedure. Analysis of the MR imaging data showed changes consistent with increased myelination in the region of the transplantation, and which progressed over time and persisted after the withdrawal of immunosuppression at nine months. The results support the conclusion of durable cell engraftment and donor-derived myelin in the transplanted patients' brains. The development of new myelin signals is unprecedented in patients with connatal PMD. In addition, clinical assessment revealed small but measureable gains in motor and/or cognitive function in three of the four patients; the fourth patient remained clinically stable. While clinical benefit cannot be confirmed without a controlled study, these clinical outcomes suggest the HuCNS-SC cells may be having a beneficial effect on the patients.

The second paper, whose lead author is Nobuko Uchida, Vice President of Stem Cell Biology at StemCells, Inc., describes research which shows that when HuCNS-SC cells were transplanted into the shiverer mouse, a common model of severe central nervous system (CNS) dysmyelination, the cells formed new, functional myelin in the mice. Sophisticated analytical techniques were used to confirm that changes measured by MR images were in fact derived from new human myelin generated by the transplanted HuCNS-SC cells. MR imaging is routinely used in the diagnosis and clinical characterization of demyelinating diseases such as multiple sclerosis, and these results supported the use of similar techniques to detect and evaluate the degree of myelination in the Phase I PMD trial. Moreover, the new myelin was shown to be functional as conductivity of nerve impulses in the mice was enhanced.

"Demonstration of functional myelin formation in animals showing disease symptoms is significant and opens up the potential to treat patients with a range of severe myelin disorders," said Stephen A. Back, MD, PhD, professor of pediatrics and neurology at Oregon Health & Science University Doernbecher Children's Hospital, and senior author of the preclinical paper.

Stephen Huhn, MD, FACS, FAAP, Vice President and Head of the CNS Program at StemCells, Inc., added, "Having these two papers published concurrently illustrates the direct pathway of how we are translating groundbreaking scientific research to the clinical setting. The data in these papers make a powerful statement about the potential of our HuCNS-SC cells to address not only PMD, but a wide spectrum of myelination disorders. We are actively moving forward with our plans to conduct a controlled Phase II clinical study in PMD and evaluating our next steps with respect to other myelination disorders."

Conference Call

StemCells, Inc. will host a live webcast, today, October 10, at 4:30 p.m. Eastern Time (1:30 p.m. Pacific Time) to discuss the data reported in these papers. Interested parties are invited to view the webcast over the Internet via the link at http://www.stemcellsinc.com/News-Events/Events.htm. An archived version of the webcast will be available for replay on the Company's website approximately two hours following the conclusion of the live event and will be available for a period of 30 days.

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StemCells, Inc. Announces Simultaneous Publication of Preclinical and Clinical Results of Its Neural Stem Cells for ...

Public release date: 10-Oct-2012 [ | E-mail | Share ]

Contact: Jennifer O'Brien jennifer.obrien@ucsf.edu 415-502-6397 University of California - San Francisco

A Phase I clinical trial led by investigators from the University of California, San Francisco and sponsored by Stem Cells Inc., showed that neural stem cells successfully engrafted into the brains of patients and appear to have produced myelin.

The study, published in the Oct. 10, 2012 issue of Science Translational Medicine, also demonstrated that the neural stem cells were safe in the patients' brains one year post transplant.

The results of the investigation, designed to test safety and preliminary efficacy, are encouraging, said principal investigator David H. Rowitch, MD, PhD, a professor of pediatrics and neurological surgery at UCSF, chief of neonatology at UCSF Benioff Children's Hospital and a Howard Hughes Medical Institute Investigator.

"For the first time, we have evidence that transplanted neural stem cells are able to produce new myelin in patients with a severe myelination disease," said Nalin Gupta, MD, PhD, associate professor of neurological surgery and pediatrics and chief of pediatric neurological surgery at UCSF Benioff Children's Hospital, and co-principal investigator of the PMD clinical trial.

"We also saw modest gains in neurological function, and while these can't necessarily be attributed to the intervention because this was an uncontrolled trial with a small number of patients, the findings represent an important first step that strongly supports further testing of this approach as a means to treat the fundamental pathology in the brain of these patients."

In the trial, human neural stem cells developed by StemCells, Inc., of Newark, California, were injected directly into the brains of four young children with an early-onset, fatal form of a condition known as Pelizaeus-Merzbacher disease (PMD).

In PMD, an inherited genetic defect prevents brain cells called oligodendrocytes from making myelin, a fatty material that insulates white matter which serves as a conduit for nervous impulses throughout the brain. Without myelin sheathing, white matter tracts short-circuit like bare electrical wires and are unable to correctly propagate nerve signals, resulting in neurological dysfunction and neurodegeneration. Patients with early-onset PMD cannot walk or talk, often have trouble breathing and undergo progressive neurological deterioration leading to death between ages 10 and 15.The disease usually occurs in males.

Multiple sclerosis and certain forms of cerebral palsy also involve damage to oligodendrocytes and subsequent demyelination.

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UCSF study shows evidence that transplanted neural stem cells produced myelin

(Update) Stem cell research brings British-Japanese pair Nobel (10-08 17:56) Shinya Yamanaka of Japan and John B. Gurdon of Britain won the Nobel Medicine Prize on Monday for their groundbreaking work on stem cells, the jury said. The pair were honoured "for the discovery that mature cells can be reprogrammed to become pluripotent,'' it said. The two discovered "that mature, specialised cells can be reprogrammed to become immature cells capable of developing into all tissues of the body,'' it said. By reprogramming human cells, "scientists have created new opportunities to study diseases and develop methods for diagnosis and therapy,'' the Nobel committee said. Gurdon is currently at the Gurdon Institute in Cambridge, while Yamanaka (pictured) is a professor at Kyoto University in Japan. Because of the economic crisis, the Nobel Foundation has slashed the prize sum to eight million Swedish kronor (HK$9.3 million) per award, down from the 10 million kronor awarded since 2001. Last year, the honour went to Bruce Beutler of the United States, Jules Hoffmann of Luxembourg and Ralph Steinman of Canada, for their groundbreaking work on the immune system. This year's laureates will receive their prize at a formal ceremony in Stockholm on December 10, the anniversary of prize founder Alfred Nobel's death in 1896.

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(Update) Stem cell research brings British-Japanese pair Nobel

Published on 09 October 2012 Hits: 182 Written by AFP

STOCKHOLM: Shinya Yamanaka of Japan and John Gurdon of the United Kingdom won the Nobel Medicine Prize on Monday for their groundbreaking work on stem cells, the jury said.

The pair were honored for the discovery that mature cells can be reprogrammed to become pluripotent, it said.

The two discovered that mature, specialized cells can be reprogrammed to become immature cells capable of developing into all tissues of the body, it said.

By reprogramming human cells, scientists have created new opportunities to study diseases and develop methods for diagnosis and therapy, the Nobel committee said.

Gurdon is currently at the Gurdon Institute in Cambridge, while Yamanaka is a professor at Kyoto University in Japan.

Because of the economic crisis, the Nobel Foundation has slashed the prize sum to eight million Swedish kronor ($1.2 million or 930,000 euros) per award, down from the 10 million kronor awarded since 2001.

Last year, the honor went to Bruce Beutler of the United States, Jules Hoffmann of Luxembourg and Ralph Steinman of Canada, for their groundbreaking work on the immune system.

This years laureates will receive their prize at a formal ceremony in Stockholm on December 10, the anniversary of prize founder Alfred Nobels death in 1896.

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British-Japanese duo win Nobel

Japanese, Briton win Nobel Medicine Prize for groundbreaking work on stem cells

Shinya Yamanaka of Japan and John B. Gurdon of Britain won the Nobel Medicine Prize on Monday for their groundbreaking work on stem cells, Agence France Presse (AFP) reports.

The pair were honoured "for the discovery that mature cells can be reprogrammed to become pluripotent," it said.

The two discovered "that mature, specialised cells can be reprogrammed to become immature cells capable of developing into all tissues of the body," it said.

By reprogramming human cells, "scientists have created new opportunities to study diseases and develop methods for diagnosis and therapy," the Nobel committee said.

Gurdon is currently at the Gurdon Institute in Cambridge, while Yamanaka is a professor at Kyoto University in Japan.

Because of the economic crisis, the Nobel Foundation has slashed the prize sum to eight million Swedish kronor ($1.2 million, 930,000 euros) per award, down from the 10 million kronor awarded since 2001.

Last year, the honour went to Bruce Beutler of the United States, Jules Hoffmann of Luxembourg and Ralph Steinman of Canada, for their groundbreaking work on the immune system.

This year's laureates will receive their prize at a formal ceremony in Stockholm on December 10, the anniversary of prize founder Alfred Nobel's death in 1896.nepalnews.com

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Japanese, Briton win Nobel Medicine Prize for groundbreaking work on stem cells