Links for Keyword: Stem Cells

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By Susan Gubar After the births of my babies in the ’70s, the umbilical cord connecting them to me was cut and trashed. But these days the blood inside can be preserved in a bank. It contains stem cells with the potential to save the lives of patients with leukemia, lymphoma or sickle cell disease. Stem cell treatments have been in the news lately because some companies are accused of selling unproven treatments that may actually harm patients. Earlier this month, the New York attorney general filed suit against one such company, claiming it knowingly performed rogue procedures on patients with a wide range of medical conditions. But there are legitimate lifesaving uses of cord blood that should not be tainted by these sham companies. Liars and thieves must not be allowed to detract from meticulous scientific research that has made umbilical cord blood mystic in its regenerative powers. A reader who is pregnant and whose first child had undergone successful leukemia treatments asked me about cord blood banking recently. Her obstetrician had suggested she bank her new baby’s cord blood as an insurance policy in case her first child suffered a recurrence. Cord blood transplants can be used to reconstitute a patient’s immune system. Blood from a sibling stands a good chance of being a suitable match for a transplant. Two impediments may influence parents against the risk-free practice of banking cord blood. First, some obstetricians believe that a brief wait before the clamping of an umbilical cord can enhance a child’s well-being, but delayed clamping compromises the volume and quality of collected cord blood cells. © 2019 The New York Times Company

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 26150 - Posted: 04.18.2019

John D. Loike, Martin Grumet On February 18, 2019, The Asahi Shimbun reported, “Ministry [of Health, Labor and Welfare in Japan] OKs 1st iPS [induced pluripotent stem] cell therapy for spinal cord injuries.” This announcement disseminated at a press conference has been viewed as an exciting clinical trial on the use of stem cells to treat spinal cord injury. However, caution is warranted here, for at least three reasons: the uncertainty of the stem cell type to be used in their clinical trial, the safety of transplanting stem cells into humans, and the responsibility of scientists and the press to communicate clearly the benefits and risks of the stem cell treatments, especially to desperate patients who would seek such unproven treatments. First, reports of the announcement by the lead scientist Hideyuki Okano of Keio University School of Medicine provide no indication where this trial is described or registered. It is of concern that it is not listed at clinicaltrials.gov or Japanese registries including UMIN Clinical Trials Registry (UMIN-CTR) and the Japan Medical Association Center for Clinical Trials (JMACCT). Second, Okano’s group reported in a study on mice that transplanted human iPSC-derived neural stem/progenitor cells (NSPC) retain unwanted proliferative characteristics, which they attributed to karyotype abnormalities. To protect against these abnormalities, Okano and colleagues have developed a “Fail-Safe System against Potential Tumorigenicity after Transplantation of iPSC Derivatives,” to quote the title of their report. Based on their results, they stated in the study that their technique “may serve as an important countermeasure against post-transplantation adverse events in stem cell transplant therapies.” However, they also caution that “a number of problems . . . need to be resolved, and at present [the Fail-Safe System] is still not suitable for clinical application.” © 1986 - 2019 The Scientist

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 26021 - Posted: 03.09.2019

By Kelly Servick SAN DIEGO, CALIFORNIA—If a diseased or injured brain has lost neurons, why not ask other cells to change jobs and pick up the slack? Several research teams have taken a first step by "reprogramming" abundant nonneuronal cells called astrocytes into neurons in the brains of living mice. "Everybody is astonished, at the moment, that it works," says Nicola Mattugini, a neurobiologist at Ludwig Maximilian University in Munich, Germany, who presented the results of one such experiment here at the annual meeting of the Society for Neuroscience last week. Now, labs are turning to the next questions: Do these neurons function like the lost ones, and does creating neurons at the expense of astrocytes do brain-damaged animals any good? Many researchers remain skeptical on both counts. But Mattugini's team, led by neuroscientist Magdalena Götz, and two other groups presented evidence at the meeting that reprogrammed astrocytes do, at least in some respects, impersonate the neurons they're meant to replace. The two other groups also shared evidence that reprogrammed astrocytes help mice recover movement lost after a stroke. Some see the approach as a potential alternative to transplanting stem cells (or stem cell–derived neurons) into the damaged brain or spinal cord. Clinical trials of that strategy are already underway for conditions including Parkinson's disease and spinal cord injury. But Gong Chen, a neuroscientist at Pennsylvania State University in State College, says he got disillusioned with the idea after finding in his rodent experiments that transplanted cells produced relatively few neurons, and those few weren't fully functional. The recent discovery that mature cells can be nudged toward new fates pointed to a better approach, he says. His group and others took aim at the brain's most abundant cell, the star-shaped astrocyte. © 2018 American Association for the Advancement of Science

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 25687 - Posted: 11.15.2018

By TAMAR LEWIN Nearly 40 years after the world was jolted by the birth of the first test-tube baby, a new revolution in reproductive technology is on the horizon — and it promises to be far more controversial than in vitro fertilization ever was. Within a decade or two, researchers say, scientists will likely be able to create a baby from human skin cells that have been coaxed to grow into eggs and sperm and used to create embryos to implant in a womb. The process, in vitro gametogenesis, or I.V.G., so far has been used only in mice. But stem cell biologists say it is only a matter of time before it could be used in human reproduction — opening up mind-boggling possibilities. With I.V.G., two men could have a baby that was biologically related to both of them, by using skin cells from one to make an egg that would be fertilized by sperm from the other. Women with fertility problems could have eggs made from their skin cells, rather than go through the lengthy and expensive process of stimulating their ovaries to retrieve their eggs. “It gives me an unsettled feeling because we don’t know what this could lead to,” said Paul Knoepfler, a stem cell researcher at the University of California, Davis. “You can imagine one man providing both the eggs and the sperm, almost like cloning himself. You can imagine that eggs becoming so easily available would lead to designer babies.” © 2017 The New York Times Company

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 23622 - Posted: 05.17.2017

By Emma Hiolski Imagine cells that can move through your brain, hunting down cancer and destroying it before they themselves disappear without a trace. Scientists have just achieved that in mice, creating personalized tumor-homing cells from adult skin cells that can shrink brain tumors to 2% to 5% of their original size. Although the strategy has yet to be fully tested in people, the new method could one day give doctors a quick way to develop a custom treatment for aggressive cancers like glioblastoma, which kills most human patients in 12–15 months. It only took 4 days to create the tumor-homing cells for the mice. Glioblastomas are nasty: They spread roots and tendrils of cancerous cells through the brain, making them impossible to remove surgically. They, and other cancers, also exude a chemical signal that attracts stem cells—specialized cells that can produce multiple cell types in the body. Scientists think stem cells might detect tumors as a wound that needs healing and migrate to help fix the damage. But that gives scientists a secret weapon—if they can harness stem cells’ natural ability to “home” toward tumor cells, the stem cells could be manipulated to deliver cancer-killing drugs precisely where they are needed. Other research has already exploited this method using neural stem cells—which give rise to neurons and other brain cells—to hunt down brain cancer in mice and deliver tumor-eradicating drugs. But few have tried this in people, in part because getting those neural stem cells is hard, says Shawn Hingtgen, a stem cell biologist at the University of North Carolina in Chapel Hill. © 2017 American Association for the Advancement of Science.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 11: Emotions, Aggression, and Stress
Link ID: 23178 - Posted: 02.02.2017

Alison Abbott It isn’t a scam, as neuroscientist Elena Cattaneo had first assumed. A total stranger really has left the prominent Italian, who is also a senator and a relentless campaigner against the misuse of science, his entire fortune to distribute for research. The sum is likely to be upwards of €1.5 million (US$1.7 million). The short, handwritten will of Franco Fiorini, an accountant from the small town of Molinella near Bologna, was officially made public on 21 June. “I’ll never know for sure why he decided to do this,” says Cattaneo, who adds that she has wept with regret that she cannot thank Fiorini. “But it gives a hopeful message that there are some people like Franco who are able to work out on their own the importance of science and research for Italy’s future.” She intends to make the money available for fellowships for young scientists in Italy, where funds for research are notoriously scarce. Cattaneo, who is based at the University of Milan, is no ordinary researcher. In 2013, then-president Giorgio Napolitano appointed her a senator-for-life in recognition of her activities in promoting science. One of her most famous achievements, made with a handful of colleagues, was a successful two-year battle to stop the Stamina Foundation in Brescia from administering unproven stem-cell therapies. Fiorini died on 21 May at the age of 64. A wheelchair user since a bout of childhood polio left him partially paralysed, he had been director of a construction company in Molinella before taking early retirement 15 years ago. © 2016 Macmillan Publishers Limited,

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 22349 - Posted: 06.23.2016

Megan Scudellari Shinya Yamanaka looked up in surprise at the postdoc who had spoken. “We have colonies,” Kazutoshi Takahashi said again. Yamanaka jumped from his desk and followed Takahashi to their tissue-culture room, at Kyoto University in Japan. Under a microscope, they saw tiny clusters of cells — the culmination of five years of work and an achievement that Yamanaka hadn't even been sure was possible. Two weeks earlier, Takahashi had taken skin cells from adult mice and infected them with a virus designed to introduce 24 carefully chosen genes. Now, the cells had been transformed. They looked and behaved like embryonic stem (ES) cells — 'pluripotent' cells, with the ability to develop into skin, nerve, muscle or practically any other cell type. Yamanaka gazed at the cellular alchemy before him. “At that moment, I thought, 'This must be some kind of mistake',” he recalls. He asked Takahashi to perform the experiment again — and again. Each time, it worked. Over the next two months, Takahashi narrowed down the genes to just four that were needed to wind back the developmental clock. In June 2006, Yamanaka presented the results to a stunned room of scientists at the annual meeting of the International Society for Stem Cell Research in Toronto, Canada. He called the cells 'ES-like cells', but would later refer to them as induced pluripotent stem cells, or iPS cells. “Many people just didn't believe it,” says Rudolf Jaenisch, a biologist at the Massachusetts Institute of Technology in Cambridge, who was in the room. But Jaenisch knew and trusted Yamanaka's work, and thought it was “ingenious”. © 2016 Macmillan Publishers Limited,

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 22324 - Posted: 06.15.2016

by Colin Barras It's like pulling a rabbit out of a hat. Researchers have reached inside the brain of a rat and pulled out neural stem cells – without harming the animal. Since the technique uses nanoparticles already approved for use in humans, it is hoped that it could be used to extract neural stem cells (NSCs) from people to treat conditions like Parkinson's, Huntington's and multiple sclerosis. Extracting NSCs from the person who needs them would avoid immune rejection – but they are difficult to remove safely. So Edman Tsang at the University of Oxford and his colleagues have developed a technique to safely fish out NSCs that originate in cavities in the brain called ventricles. Tsang's team coated magnetic nanoparticles with antibodies that bond tightly to a protein found on the surface of NSCs. They then injected the nanoparticles into the lateral ventricles of rats' brains. Six hours later, after the nanoparticles had bonded to the NSCs, the researchers used a magnetic field around the rats' heads to pull the stem cells together. They could then be sucked out of the brain with a syringe. After freeing the stem cells from the nanoparticles, the team found they could grow them in a dish, suggesting they were undamaged by the process. The rats, meanwhile, were back on their feet within hours of the surgery, showing no ill effects. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: Development of the Brain
Link ID: 18737 - Posted: 10.03.2013

by Andy Coghlan Normal adult cells have been reprogrammed to become stem cells inside live mice for the first time. As stem cells can be coaxed into developing into almost any kind of cell, being able to prompt this behaviour in the body could one day be used to repair ailing organs including the heart, liver, spinal cord and pancreas. "By doing it in situ, the cells are already there in the tissue, in the right position," says Manuel Serrano at the Spanish National Cancer Research Centre in Madrid, and co-leader of the new work. The technique overcomes the difficulties inherent in making cells outside the body, grafting them into people, and then of potential rejection. It opens up new clinical opportunities, say the researchers. Since 2006, when Nobel-prizewinning researcher Shinya Yamanaka first made adult cells return to a stem-cell-like state of being pluripotent – able to turn into almost any cell type – all such induced pluripotent stem (iPS) cells have been made in vitro. This is done by taking a sample of adult cells, such as skin cells, and treating them with four proteins that rewind the cells back to an embryonic-like state. Serrano genetically altered mice to give them extra copies of the four genes that produce these proteins: Oct, Sox2, Klf4 and c-Myc. The genes were programmed to kick into action when exposed to doxycycline, an antibiotic. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 18639 - Posted: 09.12.2013

Meredith Wadman The woman was four months pregnant, but she didn't want another child. In 1962, at a hospital in Sweden, she had a legal abortion. The fetus — female, 20 centimetres long and wrapped in a sterile green cloth — was delivered to the Karolinska Institute in northwest Stockholm. There, the lungs were dissected, packed on ice and dispatched to the airport, where they were loaded onto a transatlantic flight. A few days later, Leonard Hayflick, an ambitious young microbiologist at the Wistar Institute for Anatomy and Biology in Philadelphia, Pennsylvania, unpacked that box. Working with a pair of surgical scalpels, Hayflick minced the lungs — each about the size of an adult fingertip — then placed them in a flask with a mix of enzymes that fragmented them into individual cells. These he transferred into several flat-sided glass bottles, to which he added a nutrient broth. He laid the bottles on their sides in a 37 °C incubation room. The cells began to divide. So began WI-38, a strain of cells that has arguably helped to save more lives than any other created by researchers. Many of the experimental cell lines available at that time, such as the famous HeLa line, had been grown from cancers or were otherwise genetically abnormal. WI-38 cells became the first 'normal' human cells available in virtually unlimited quantities to scientists and to industry and, as a result, have become the most extensively described and studied normal human cells available to this day. © 2013 Nature Publishing Group

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 18358 - Posted: 07.09.2013

By David Brown, A team of researchers said Wednesday that it had produced embryonic stem cells — a possible source of disease-fighting spare parts — from a cloned human embryo. Scientists at the Oregon Health and Science University accomplished in humans what has been done over the past 15 years in sheep, mice, cattle and several other species. The achievement is likely to, at least temporarily, reawaken worries about “reproductive cloning” — the production of one-parent duplicate humans. But few experts think that production of stem cells through cloning is likely to be medically useful soon, or possibly ever. “An outstanding issue of whether it would work in humans has been resolved,” said Rudolf Jaenisch, a biologist at MIT’s Whitehead Institute in Cambridge, Mass., who added that he thinks the feat “has no clinical relevance.” “I think part of the significance is technical and part of the significance is historical,” said John Gearhart, head of the Institute for Regenerative Medicine at the University of Pennsylvania. “Many labs attempted it, and no one had ever been able to achieve it.” A far less controversial way to get stem cells is now available. It involves reprogramming mature cells (often ones taken from the skin) so that they return to what amounts to a second childhood from which they can grow into a new and different adulthood. Learning how to make and manipulate those “induced pluripotent stem” (IPS) cells is one of biology’s hottest fields. © 1996-2013 The Washington Post

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 18162 - Posted: 05.16.2013

By Meghan Rosen Mouse brain cells scamper close to eternal life: They can actually outlive their bodies. Mouse neurons transplanted into rat brains lived as long as the rats did, surviving twice as long as the mouse’s average life span, researchers report online February 25 in the Proceedings of the National Academy of Sciences. The findings suggest that long lives might not mean deteriorating brains. “This could absolutely be true in other mammals — humans too,” says study author Lorenzo Magrassi, a neurosurgeon at the University of Pavia in Italy. The findings are “very promising,” says Carmela Abraham, a neuroscientist at Boston University. “The question is: Can neurons live longer if we prolong our life span?” Magrassi’s experiment, she says, suggests the answer is yes. One theory about aging, Magrassi says, is that every species has a genetically determined life span and that all the cells in the body wear out and die at roughly the same time. For the neurons his team studied, he says, “We have shown that this simple idea is certainly not true.” Magrassi’s team surgically transplanted neurons from embryonic mice with an average life span of 18 months into rats. To do so, the researchers slipped a glass microneedle through the abdomens of anesthetized pregnant mice. Then, using a dissecting microscope and a tool to illuminate the corn-kernel-sized mouse embryos, the researchers scraped out tiny bits of brain tissue and injected the neurons into fetal rat brains. After the rat pups were born, Magrassi and colleagues waited as long as three years, until the animals were near death, to euthanize the rats and dissect their brains. © Society for Science & the Public 2000 - 2013

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 17846 - Posted: 02.26.2013

Monya Baker Some of the waste that humans flush away every day could become a powerful source of brain cells to study disease, and may even one day be used in therapies for neurodegenerative diseases. Scientists have found a relatively straightforward way to persuade the cells discarded in human urine to turn into valuable neurons. The technique, described online in a study in Nature Methods this week1, does not involve embryonic stem cells. These come with serious drawbacks when transplanted, such as the risk of developing tumours. Instead, the method uses ordinary cells present in urine, and transforms them into neural progenitor cells — the precursors of brain cells. These precursor cells could help researchers to produce cells tailored to individuals more quickly and from more patients than current methods. Researchers routinely reprogram cultured skin and blood cells2 into induced pluripotent stem (iPS) cells, which can go on to form any cell in the body. But urine is a much more accessible source. Stem-cell biologist Duanqing Pei and his colleagues at China's Guangzhou Institutes of Biomedicine and Health, part of the Chinese Academy of Sciences, had previously shown that kidney epithelial cells in urine could be reprogrammed into iPS cells. However, in that study the team used retroviruses to insert pluripotency genes into cells — a common technique in cell reprogramming. This alters the genetic make-up of cells and can make them less predictable, so in this study, Pei and his colleagues introduced the genes using vectors which did not integrate in the cellular genome. © 2012 Nature Publishing Group,

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 17588 - Posted: 12.10.2012

by Emily Underwood 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 Parkinson's 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 can't 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 wouldn't expect lumber to assemble itself into a house," he notes, yet neurons in a newborn baby's 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. © 2010 American Association for the Advancement of Science

Related chapters from BN: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: Development of the Brain
Link ID: 17356 - Posted: 10.11.2012

By Tina Hesman Saey The 2012 Nobel Prize in physiology or medicine was awarded for the discovery that adult cells can be reprogrammed, as scientists did to these neurons, created from skin cells reprogrammed into a type of primordial stem cell and then coaxed into brain cells that control movement.G. Croft and M. Weygandt/The Cell: An Image Library Two scientists who showed that a cell's fate is reversible have won the 2012 Nobel Prize in physiology or medicine. The Nobel committee announced October 8 that John Gurdon and Shinya Yamanaka are being honored for showing that cells once thought to be locked into a specific identity could remember and revert to the supremely flexible state they have in an early embryo. Gurdon’s 1962 work forever changed the view that adult cells are stuck in their fate. In a series of experiments, he transplanted the nucleus — the cellular compartment that contains DNA — from an intestinal cell of an adult frog into a frog egg cell from which the nucleus had been removed. The cell developed into a normal tadpole, demonstrating that DNA contains all the information necessary to make an embryo. More than four decades later, Yamanaka, of Kyoto University in Japan, changed the debate over stem cells when he created induced pluripotent stem cells, which are capable of becoming nearly any cell in the body. He was trying to understand the factors that make stem cells isolated from embryos so malleable; many genes seemed to be involved. Yamanaka used viruses to insert combinations of candidate genes into skin cells, and found that only four genes are required to turn a mouse skin cell into a stem cell. The technique has since been used to convert adult human cells into embryonic-like cells and even to convert skin cells directly into heart or brain cells. © Society for Science & the Public 2000 - 2012

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 17346 - Posted: 10.09.2012

Two pioneers of stem cell research have shared the Nobel prize for medicine or physiology. John Gurdon from the UK and Shinya Yamanaka from Japan were awarded to prize for transforming specialised cells into stem cells.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 17342 - Posted: 10.08.2012

by Dennis Normile YOKOHAMA, JAPAN—For more than a decade, stem cell therapies have been touted as offering hope for those suffering from genetic and degenerative diseases. The promise took another step toward reality last week with announcements here at the annual meeting of the International Society for Stem Cell Research (ISSCR) that two groups are moving forward with human clinical research, one focusing on a rare genetic neurological disease and the other for the loss of vision in the elderly. StemCells Inc. of Newark, California, reported encouraging results of an initial human trial using human neural stem cells to treat Pelizaeus-Merzbacher disease (PMD). PMD is a progressive and fatal disorder in which a genetic mutation inhibits the normal growth of myelin, a protective material that envelopes nerve fibers in the brain. Without myelin, nerve signals are lost, and the patient, usually an infant, suffers degenerating motor coordination and other neurological symptoms. In her presentation, Ann Tsukamoto, StemCells' vice president for research, said the company chose to test its neural stem cell approach on PMD because there is currently no treatment for the condition and a diagnosis can be confirmed by genetic testing and magnetic resonance imaging. "This creates an opportunity for early intervention when it can best help." The company has created banks of highly purified neural stem cells that are isolated from adult neural tissue. Injected into rodents, the cells don't form tumors; rather, they migrate through the animals' brains, where they differentiate into various types of neural cells including the cells that create the myelin that protects nerve fibers. When neural stem stems were injected into in mice, they showed "robust engraftment and migration, the formation of new myelin," Tsukamoto said. © 2010 American Association for the Advancement of Science

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 16932 - Posted: 06.19.2012

David Cyranoski A stem-cell biologist has had an eye-opening success in his latest effort to mimic mammalian organ development in vitro. Yoshiki Sasai of the RIKEN Center for Developmental Biology (CBD) in Kobe, Japan, has grown the precursor of a human eye in the lab. The structure, called an optic cup, is 550 micrometres in diameter and contains multiple layers of retinal cells including photoreceptors. The achievement has raised hopes that doctors may one day be able to repair damaged eyes in the clinic. But for researchers at the annual meeting of the International Society for Stem Cell Research in Yokohama, Japan, where Sasai presented the findings this week, the most exciting thing is that the optic cup developed its structure without guidance from Sasai and his team. “The morphology is the truly extraordinary thing,” says Austin Smith, director of the Centre for Stem Cell Research at the University of Cambridge, UK. Until recently, stem-cell biologists had been able to grow embryonic stem-cells only into two-dimensional sheets. But over the past four years, Sasai has used mouse embryonic stem cells to grow well-organized, three-dimensional cerebral-cortex1, pituitary-gland2 and optic-cup3 tissue. His latest result marks the first time that anyone has managed a similar feat using human cells. The various parts of the human optic cup grew in mostly the same order as those in the mouse optic cup. This reconfirms a biological lesson: the cues for this complex formation come from inside the cell, rather than relying on external triggers. © 2012 Nature Publishing Group,

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 7: Vision: From Eye to Brain
Link ID: 16921 - Posted: 06.16.2012

By James Gallagher Health and science reporter, BBC News Skin cells have been converted directly into cells which develop into the main components of the brain, by researchers studying mice in California. The experiment, reported in Proceedings of the National Academy of Sciences, skipped the middle "stem cell" stage in the process. The researchers said they were "thrilled" at the potential medical uses. Far more tests are needed before the technique could be used on human skin. Stem cells, which can become any other specialist type of cell from brain to bone, are thought to have huge promise in a range of treatments. Many trials are taking place, such as in stroke patients or specific forms of blindness. One of the big questions for the field is where to get the cells from. There are ethical concerns around embryonic stem cells and patients would need to take immunosuppressant drugs as any stem cell tissue would not match their own. An alternative method has been to take skin cells and reprogram them into "induced" stem cells. These could be made from a patient's own cells and then turned into the cell type required, however, the process results in cancer-causing genes being activated. The research group, at the Stanford University School of Medicine in California, is looking at another option - converting a person's own skin cells into specialist cells, without creating "induced" stem cells. It has already transformed skin cells directly into neurons. BBC © 2012

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 16323 - Posted: 01.31.2012

Charlotte Schubert Human neurons, derived from embryonic stem cells, can modulate the behavior of a network of host neurons, according to a study examining the cells in culture and transplanting them into a mouse brain. The findings, published today in the Proceedings of the National Academy of Sciences, lay the foundations for potential future treatments of Parkinson's disease, stroke and other conditions. Previous studies have shown that transplanted human neurons derived from stem cells look and act like functional nerve cells. For instance, such cells form connections with host neurons in the mouse brain, and receive signals from them. But it has been a challenge to show that the transplanted cells can successfully signal to and regulate the behaviour of host neurons. To address this question, Jason Weick and his colleagues at the University of Wisconsin in Madison harnessed a technique known as optogenetic targeting. This involves genetically engineering neurons to produce an ion channel (a protein-lined pore that spans the cell membrane) that opens in response to light, allowing positive ions such as sodium and calcium to flow through it and activate the neuron. In this way the researchers can selectively activate human neurons in a mixture of human and mouse cells. © 2011 Nature Publishing Group,

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 15: Language and Lateralization
Link ID: 16064 - Posted: 11.22.2011