Stem Cell Research

New Method Of Directing Stem Cells To Increase Bone Formation And Strength Developed

Directing stem cells to travel and adhere to the surface of bone for bone formation has been among the elusive goals in regenerative medicine. 

This new method enhances bone growth by using a unique hybrid molecule, LLP2A-alendronate. When injected into the bloodstream LLP2A-alendronate directs the body's stem cells to travel to the surface of bones. Once there the stem cells differentiate into bone-forming cells and synthesize proteins to enhance bone growth.

"There are many stem cells, even in elderly people, but they do not readily migrate to bone," said Wei Yao M.D., Assistant Professor, Center for Aging, UC Davis. "Finding a molecule that attaches to stem cells and guides them to the targets we need is a real breakthrough."

From Stem Cell Research To Genetics, Oxford And Harvard Lead In Data-Sharing Effort

In a move sorely needed in the new and fast growing field of stem cell research and regenerative medicine, more than 50 collaborators at over 30 scientific organizations around the globe have agreed on a common standard that will make possible the consistent description of enormous and very different databases compiled in fields ranging from genetics to stem cell research and therapies.

The new standard provides a way for scientists in widely disparate fields to co-ordinate each other's findings by allowing behind-the-scenes combination of the mountains of data produced by modern, technology driven science.

Skin Cells Turned Into Neural Precusors, Bypassing Stem Cell Stage

New research has converted mouse skin cells directly into cells that become the three main parts of the nervous system. The finding is an extension of a previous study (post)  by the same group showing that mouse and human skin cells can be directly converted into functional neurons.

Importantly, the multiple successes of the direct conversion method could refute the idea that pluripotency is necessary for a cell to transform from one cell type to another. Together, the results raise the possibility that embryonic stem cell research and another technique called “induced pluripotency” could be supplanted by a more direct way of generating specific types of cells for therapy or research.

This new research is a substantial advance over the previous work in that it transforms the skin cells into neural precursor cells as opposed to neurons. While neural precursor cells can differentiate into neurons they can also become the two other main cell types in the nervous system: astrocytes and oligodendrocytes.

Therapeutically Useful Stem Cell Derivatives Need Stability

New research suggests that neural derivatives of human pluripotent stem cells frequently acquire extra material from chromosome 1q, a chromosomal defect that has been associated with some blood cell cancers and pediatric brain tumors with poor clinical outcomes. 

The good news is that the same researchers found that the abnormal neural cells detected were unable to form tumors in mice.  The new cautionary data however does suggests the necessity of additional quality controls to ensure that neural derivatives of human pluripotent stem cells are not genomically unstable, a common characteristic of cancer cells.  The research was accomplished by Natalie Lefort and colleagues, at the Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, France.

In commentary concerning the research, Neil Harrison, at the University of Sheffield, United Kingdom, noted that while the data raise safety issues relevant for the therapeutic use of these cells, the fact that the same chromosome was affected in all cases suggests that it should be possible to design screening strategies to detect and remove these cells.

Adapted from the Institute for Stem Cell therapy and Exploration of Monogenic Diseases announcement.

 

Researchers Find First Step In Strategy For Parkinson's Disease Induced Pluripotent Stem Cell Replacement Therapy

Induced pluripotent stem cells (iPSC) are a promising avenue for cell replacement therapy in neurologic diseases. For example, mouse and human iPSCs have been used to generate dopaminergic (DA) neurons that improve symptoms in rat Parkinson's disease models.

Now researchers have evaluated the growth, differentiation, and function of human-derived iPSC-derived neural progenitor cells (NPCs) in a primate model, and have elucidated their therapeutic potential.

"We developed a series of methods to induce human iPSCs to become NPCs, using a feeder-free culture method, and grafted NPCs at different stages of differentiation into the brain of a monkey PD* model," said Jun Takahashi, MD, PhD, of Kyoto University. "We developed a method to evaluate the growth and DA activity of the grafts using magnetic resonance imaging (MRI), positron emission tomography (PET), immunocytochemistry, and behavioral analyses, all of which will be useful in preclinical research."

Video: Irving Weisman On The Importance Of The Distinction Between Embryonic And Adult Stem Cells

The ethical argument concerning the use of embryonic stem cells continues to rage and may well be an issue in the upcoming 2012 election. The use of embryonic stem cells in research is continually questioned in some quarters on the premise that the growing success of adult stem cell research makes embryonic stem cell research unnecessary. In this four minute video Dr. Weissman explains what it's like to work with one type of cell versus the other and why the research distinction is important.

Irving Weissman is one of the older generation of stem cell pioneers.  He is a professor of pathology and developmental biology and the director of Stanford University School of Medicine's Institute of Stem Cell Biology and Regenerative Medicine.

 

In 1988, Dr. Weissman became the first to isolate in pure form any stem cell in any species when he isolated the hematopoietic or blood-forming stem cell in mice. He subsequently isolated the human hematopoietic stem cell, the human neuronal stem cell, and the human leukemia stem cell. 
Dr. Weissman's research encompasses the phylogeny and developmental biology of the cells that make up the blood-forming and immune systems.

Stem Cells Show Promise In Delivering Gene Therapy For Hunington's Disease

In a promising approach that might block the disease from advancing, researchers have developed a technique for using stem cells to deliver therapy that specifically targets the genetic abnormality found in Huntington's disease. Huntington's disease can be managed with medications, but currently there are no treatments for the physical, mental and behavioral decline of its victims.

"We have been able to successfully deliver inhibitory RNA sequences from stem cells directly into neurons, significantly decreasing the synthesis of the abnormal huntingtin protein," said Jan A. Nolta, Director of the UC Davis stem cell program and the UC Davis Institute for Regenerative Cures.

Human Pluripotent Stem Cells Induced To Become High Purity Vascular Smooth Muscle

Using human pluripotent stem cells, researchers have discovered a method for creating high purity vascular smooth muscle. 

Although blood and cardiac cells from human pluripotent stem cells have been created before, this is the first time that all the major types of vascular smooth muscle cells have been developed in an easily scalable manner.

In the UK, one in three of all deaths is due to cardiovascular disease. The vast majority of these are caused by atherosclerosis, a ‘furring up’ and blockage of blood vessels. For patients who are unsuitable for conventional stenting or bypass treatment, one option in the future may be to grow new blood vessels to bypass their own blocked vessels.

Factor That Translates Mechanical Work In Muscles Into Chemical Growth Signal To Muscle Stem Cells Found

We take it for granted, but the fact that our muscles grow when we work them makes them rather unique. Turns out a factor produced in working muscle fibers apparently tells surrounding muscle stem cells that it's time to multiply. In other words, this serum response factor (Srf) translates the mechanical signal of work into a chemical one.

"This signal from the muscle fiber controls stem cell behavior and participation in muscle growth," says Athanassia Sotiropoulos of Inserm in France. "It is unexpected and quite interesting."

New Research Sheds Light On Early Embryonic Stem Cell Development Through First Time Birth Of Chimeric Monkeys From Stem Cells Taken From Two Separate Embryos

Conducted to gain a better understanding of the differences between natural stem cells residing in early embryos and their cultured embryonic stem cell  counterparts, the new work also determined that stem cell functions and abilities differ between primates and rodents.

The first cels studied were those that were totipotent – cells from the early embryo that have the ability to divide and produce all of the differentiated cells in the placenta and the body of an organism. These were compared with pluripotent cells – cells derived from the later stage embryo that have the ability to produce all body parts except those necessary for reproduction.

Flexible Neural Stem Cells Found In A Single Layer At The Back Of The Human Eye

That cell layer, known as the retinal pigment epithelium (RPE), underlies and supports photoreceptors in the light-sensitive retina. Without it, photoreceptors and vision are lost. The new study shows that the RPE also harbors self-renewing stem cells that can wake up to produce actively growing cultures when placed under the right conditions. They can also be coaxed into forming other cell types.

"You can get these cells from a 99-year-old," said Dr. Sally Temple, co-founder and scientific director of the Neural Stem Cell Institute in Rensselaer, New York. "These cells are laid down in the embryo and can remain dormant for 100 years. Yet you can pull them out and put them in culture and they begin dividing. It is kind of mind boggling."

Intervention With Young Stem Cells Makes Aging Mice Live Longer And Healthier

Mice bred to age too quickly seemed to have sipped from the fountain of youth after scientists at the University of Pittsburgh School of Medicine injected them with stem cell-like progenitor cells derived from the muscle of young, healthy animals.

Instead of becoming infirm and dying early as untreated mice did, animals that got the stem/progenitor cells improved their health and lived two to three times longer than expected. Previous research has revealed stem cell dysfunction, such as poor replication and differentiation, in a variety of tissues in old age, but it's not been clear whether that loss of function contributed to the aging process or was a result of it (see previous post).

Tissue Degeneration Found In Aging Is Partially Caused By Mitochondrial Dysfunction In Stem Cells

Research models have preciously found that an accumulation of mitochondrial genome defects leads to symptoms of premature aging: thin skin, graying of hair, baldness, osteoporosis and anemia.

In a breakthrough revealing the unexpected importance of energy metabolism in regulating stem cell function and tissue maintenance, new research on the mechanisms of age-associated degeneration indicates that tissue degeneration can be caused by mitochondrial dysfunction in tissue stem cells. Stem cell function may be modified with the result that progeny cells in blood and the nervous system are dysfunctional.

Stem Cell-Like Blood Progenitor Cells Receive Signals From Cells In Nearby Niche

These signals keep the progenitors in the same stem cell-like state so, when needed, they can begin differentiating into blood cells.

Now stem cell scientists have found that the blood progenitor cells receive critical signals back from the daughter blood cells they create, telling the progenitor cells when enough blood cells have been made and it's time to stop differentiating.

"The cells in the niche provide a safe environment to support blood progenitor cells," said Dr. Julian A. Martinez-Agosto, assistant professor of human genetics and pediatrics and a researcher with the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA. "When the blood progenitor cells receive signals from the niche cells it creates an environment for those cells to maintain their potential and not differentiate."

Molecules That Stimulate Stem Cells to Develop Into Beating Heart Muscle Cells Identified

To search for new molecules involved in heart development, the researchers developed a robust small molecule screen using a zebrafish system. The zebrafish is an excellent model organism to study heart growth and development because there are established genetic approaches that permit visualization of fluorescent beating hearts within the transparent embryos of zebrafish.

"Despite advances in modern medicine, management of myocardial infarction and heart failure remains a major challenge," Dr. Tao P. Zhong of Fudan University in Shanghai, China. "There is intense interest in developing agents that can influence stem cells to differentiate into cardiac cells as well as enhance the inherent regenerative capacities of the heart. Developing therapies that can stimulate heart muscle regeneration in areas of infarction would have enormous medical impact."

New Research Unlocks Origins of Blood Stem Cells

Because hematopoietic (blood) stem cells (HSCs), found in the bone marrow of adult mammals, generate all of the blood cell types of the body, unlocking the secrets of their origin may help researchers to better manipulate embryonic stem cells to generate new blood cells for therapy.

Previous studies have indicated that HSCs originated from a small population of cells lining blood vessels, called endothelial cells. But, it has been unclear precisely which endothelial cells transitioned to blood stem cells during early development.

“The ultimate goal for stem-cell therapies is to take precursor stem cells and push them down a particular lineage to replace diseased or dead cells in human adults or children,” said Nancy Speck, PhD, professor of Cell and Developmental Biology at the Perelman School of Medicine at the University of Pennsylvania. First things first, she says: “You have to understand how this happens in the embryo.”

Video Presentation by Dr. Stephen Badylak: Regenerative Medicine: Possibilities and Potential

Regenerative medicine in the form of autologous tissue or organ construction or reconstruction presented by a pioneer in the field.

Dr. Stephen Badylak is currently a Research Professor in the Department of Surgery and director of Tissue Engineering at the McGowan Institute for Regenerative Medicine at the University of Pittsburgh.

He is a Fellow of the American Institute for Medical and Biological Engineering and a charter member and one of three United States member governors of the Tissue Engineering Society International. He is also a member of the Society for Biomaterials and the Regenerative Medicine and Stem Cell Biology Society.

This talk on the status and future of regenerative medicine and the transition from current to regenerative medicine was delivered at the Singularity Summit in October of 2011.

 

Tweaking Elements In Reprogramming Of Adult Cells Can Greatly Affect The Quality Of The Resulting Induced Pluripotent Stem Cells

Since the creation of the first iPS cells in 2006, researchers using various reprogramming techniques have reported a broad spectrum of efficiency rates and quality of resulting iPS cells.

Although researchers have shown iPS cells can fulfill all developmental tests applied to ES cells, recent reports have identified molecular differences that can influence their developmental potential and render them less-than-equivalent partners to ES cells. These inconsistencies have tarnished the promise of iPS cells, dampened enthusiasm, and fueled speculation that they may never be used therapeutically.

Now research has shown that tweaking the levels of factors used during the reprogramming of adult cells into induced pluriopotent stem (iPS) cells greatly affects the quality of the resulting iPS cells.

"This conclusion is something that I think is very surprising or unexpected—that the levels of these reprogramming factors determine the quality of the iPS cells," said Whitehead Founding Member and pioneer stem cell researcher Rudolf Jaenisch. "We never thought they'd make a difference, but they do."

Newly Discovered Heart Stem Cells Make Muscle And Bone

A relatively abundant pool of stem cells in the heart have the capacity for long-term expansion and can form a variety of cell types, including muscle, bone, neural and heart cells.

The discovery may lay a foundation for much needed regenerative therapies aimed to enhance tissue repair in the heart. The damaged heart often doesn't repair itself well because of the incredibly hostile environment and wide-scale loss of cells, including stem cells, after a heart attack.

Researchers Engineer Blood Stem Cells To Fight Melanoma

In a development that could affect 40 percent of caucasians with the malignancy, researchers have demonstrated that blood stem cells can be engineered to create cancer-killing T-cells that seek out and attack human melanoma.

"Done in mouse models, this study serves as the first proof-of-principle that blood stem cells, which make every type of cell found in the blood, can be genetically altered in a living organism to create an army of melanoma-

Aging Stem Cells May Explain Higher Prevalence Of Leukemia, Infections Among Elderly

Human stem cells aren’t immune to the aging process according to new research with hematopoietic stem cells which create the cells that comprise the blood and immune system. Understanding when and how these stem cells begin to falter as the years pass may explain why some diseases, such as acute myeloid leukemia, increase in prevalence with age, and also why elderly people tend to be more vulnerable to infections such as colds and the flu.

Specifically, new research has found that hematopoietic stem cells from healthy people over age 65 make fewer lymphocytes — cells responsible for mounting an immune response to viruses and bacteria — than stem cells from healthy people between ages 20 and 35 (The cells were isolated from bone marrow samples). Instead, elderly hematopoietic stem cells, or HSCs, have a tendency to be biased in their production of another type of white blood cell called a myeloid cell. This bias may explain why older people are more likely than younger people to develop myeloid malignancies.

Recipient's Immune System Governs Stem Cell Regeneration

New research describes how different types of immune system T-cells alternately discourage and encourage stem cells to regrow bone and tissue, bringing into sharp focus the importance of the transplant recipient's immune system in stem cell regeneration.

Number Of New Heart Cells Shown To Increase By 30% Following Stem Cell Infusion

Healthy, new heart cells have been generated by animals with chronic ischemic heart disease after receiving stem cells derived from cardiac biopsies or "cardiospheres."

The new research demonstrated a 30 percent increase in healthy heart muscle cells within a month after receiving cardiosphere-derived cells (or CDCs). This finding is contrary to conventional wisdom which has held that heart cells are terminally differentiated and thus, are unable to divide.

Ischemic heart disease from coronary artery narrowing and prior heart attacks is the most common cause of heart failure. While other investigators have largely focused on regenerating muscle in scarred tissue, the new

Autism And Induced Pluripotent Stem Cells

Dr. Ricardo Dolmetsch, associate professor of neurobiology, Stanford University, has generated stem cells from the cells of children with autism. This is a straight forward, brief interview which talks to the question of stem cells and autism. During the interview Dolmetsch gives a cogent explanation of the possibilities for Induced Pluripotent Stem Cells in disease and therapeutic research.

 

 

Stem Cell Research Advanced As Key To Cell Specialization Is Discovered

New research has uncovered a mechanism that governs how cells become specialized during development.

In an attempt to determine how a fertilized egg gives rise to many different cells in the body, researchers studied cell differentiation in the fruit fly, Drosophila Melanogaster. They found that cell specialization depends on a pair of proteins that act as super regulators of proteins that were already known—one super-regulating protein encouraging a cell to differentiate and the other trying to hold back the process.

In particular, researchers studied Helix-Loop-Helix proteins, “master-regulating” proteins that were known to play a role in the differentiation of fruit fly cells such as muscle, fat and nervous-system cells. By examining eye

Novel Surface Triples Stem Cell Numbers Grown In Culture

Irradiating polystyrene lab plates with ultraviolet (UV) waves creates a surface capable of tripling the number of human embryonic stem (ES) and induced pluripotent stem (iPS) cells grown in culture by current methods. Use of this novel surface also eliminates the need for layers of mouse “feeder cells” to support ES- and iPS-cell growth.

“Polystyrene is the most common cell culture surface used in labs, and to be able to do a simple treatment and get something that works better than the mouse feeder layers is great and potentially has a lot of utility,” said Daniel Anderson, Associate Professor Harvard-MIT Division of Health Sciences & Technology.

Spinal Membrane As Source Of Stem Cells May Advance Spinal Cord Stem Cell Therapy

New research has shown that meninges, the membrane which envelops the central nervous system, is a potential source of self-renewing stem cells.

The researchers focused on spinal cord injuries caused when the spinal cord is damaged by trauma rather than disease. Depending on the severity a spinal injury can lead from pain to full paralysis, with high social and medical care costs. As the spinal cord lacks the ability to regenerate, the potential for patient recovery is severely limited.

Rejuvinated Induced Pluripotent Stem Cells Produced From Cells Of Elderly Donors, Some Over 100 Years Old

Until now, research results demonstrated that senescence (the final stage of cellular aging) was an obstacle blocking the use of stromal cells, ones that had been induced into pluripotent, embryonic-like stem cells, for therapeutic applications in elderly patients.

The researchers successfully rejuvenated cells from elderly donors, some over 100 years old, thus demonstrating the reversibility of the cellular aging process.

Personal Stem Cell Banks Might Be Staple Of Future Health Care

New research has found that old stem cells can be rejuvenated by being placed in a young microenvironment thus raising the possibility that patients’ own stem cells may one day be banked to treat their age-related diseases.

It is well known that older stem cells are not as robust as young ones. University of Texas Health Science Center researchers suspected that giving stem cells a youthful environment for growth would cause them to regenerate faster. The team extracted mesenchymal stem cells from the bone marrow of

Stem Cell Found That Is Key to Lung Regeneration

Distal airway stem cells (DASCs), a specific type of stem cells in the lungs, are involved in forming new alveoli to replace and repair damaged lung tissue according to new research.

Researchers cloned adult stem cells taken from three different parts of the lungs - nasal epithelial stem cells (NESCs), tracheal airway stem cells (TASCs) and distal airway stem cells (DASCs). Despite the three types of cells being nearly 99 percent genetically identical, the team was able to make the observation that only DASCs formed alveoli when cloned in vitro.

Programming Stem Cells to Home to Specific Tissues Should Enable More Effective Cell-based Therapies

The inability to target stem cells to tissues of interest poses a significant barrier to effective cell therapy.

New research has developed a platform approach to chemically incorporate homing receptors onto the surface of stem cells. This approach has the potential to improve the efficacy of many types of stem cell therapies by increasing the concentrations of cells at target locations in the body.

To accomplish this, researchers engineered the surface of cells to include receptors that act as a homing device.

Researchers Zero In On Drugs That Can Kill Brain Cancer Stem Cells

Glioblastoma is one of the deadliest malignancies, typically killing patients within 12 to 18 months. These brain cancers consist of two kinds of cells: a larger, heterogeneous population of tumor cells and a smaller sub-population of stem cells, which are treatment-resistant.

Now researchers have developed a screening approach to identify chemical compounds that can target and kill the stem cells responsible for creating deadly brain tumors.

"The new high-throughput molecular screening approach was specifically designed to find drugs that can target that sub-population and prevent it from

Precision At Choosing Stem Cells A Step Forward For Treating Multiple Sclerosis, Other Diseases

Researchers have improved efforts to pluck out just the right stem cells to address the brain problem at the core of multiple sclerosis and a large number of rare, fatal children’s diseases.

New research has isolated and directed stem cells from the human brain to become oligodendrocytes, the type of brain cell that makes myelin, a crucial fatty material that coats neurons and allows them to signal effectively.

Researchers injected the chosen cells into the brains of mice that were born without the ability to make myelin. Twelve weeks later, the cells had become oligodendrocytes and had coated more than 40 percent of the brain’s neurons with myelin – a four-fold improvement over previous results.

New Gene Therapy Utilizing Induced Pluripotent Stem Cells Corrects Mutation In Patient's Stem Cells

Researchers targeted a gene mutation responsible for both cirrhotic liver disease and lung emphysema and were able to correct the sequence of a genome, remove all exogenous DNA, and show that the corrected gene worked normally.

The researchers used human induced pluripotent stem cells (hIPSCs) because, once reprogrammed, these cells can be converted into a wide range of tissues. If cells from a patient with a gene defect can be corrected, scientists believe that when reintroduced into the patient they could treat the effects of the mutation causing the disease.

"Stimulated" Stem Cells Stop Donor Organ Rejection

Researchers have developed a way to stimulate a rat’s stem cells after a liver transplant as a means of preventing rejection of the new organ without the need for lifelong immunosuppressant drugs.

With a combination of a very low, short-term dose of an immunosuppressive drug to prevent immediate rejection and four doses of a medication that frees the recipient’s stem cells from the bone marrow to seek out and populate the donor organ, the rats lived more than 180 days with good liver function despite stopping both drugs after one week.

Induced Pluripotent Stem Cell State Much Easier To Achieve In New Reprogramming Approach

Researchers have found a new, more efficient, technique to reprogram human adult cells, such as skin cells, into induced pluripotent stem cells.

Until now cells have been reprogrammed using four specific regulatory proteins. By adding two further regulatory factors the new research seems to have brought about a dramatic improvement in the efficiency of reprogramming and the robustness of stem cell development.

Patent For Two-Step Process To Produce Large Numbers Of Pure Stem Cells For Transplantation After Heart Attack Granted

In the first step, cardiac cells from a biopsy are grown in a culture and identified by a stem-cell marker. In the second step the marked cells are isolated by cell sorting and grown in isolation to increase their number.

The use of cardiac stem cells helps restore heart tissue damaged by heart attacks and heart failure. Previous methods for producing such stem cells required long exposure to digestive enzymes to separate the stem cells, which normally grow in clumps.

Video: The Fundamentals Of Stem Cell Clinical Trials For Spinal Cord Repair

This talk is by Professor Alan Mackay-Sim of Griffith University, Brisbane Australia. Mackay-Sim is the Director as well as Chief Investigator for the Australian National Center for Stem Cell Research. His talk is on Cell Transplantation for Spinal Cord Repair, with reference to the methodology of clinical trials. He also addresses the Geron Corp. clinical trial currently under way as well as a clinical trial on spinal cord repair that he has undertaken.

The presentation is directed at a lay audience.

 

 

 

Expression Of Pluripotency-Associated Gene Marks Many Types Of Adult Stem Cells

Sox2 – one of the transcription factors used in the conversion of adult stem cells into induced pluripotent stem cells (iPSCs) – is expressed in many adult tissues where it had not been previously observed according to new research. The team also confirmed that Sox2-expressing cells found in the stomach, testes, cervix and other structures are true adult stem cells that can give rise to all mature cell types in those tissues.

"We have known that Sox2 is essential for maintaining pluripotency in embryonic stem cells and neural stem cells and -- with three other embryonic genes -- is sufficient to convert adult cells into Induced Pluripotent Stem Cells," said Konrad Hochedlinger, PhD, of the Massachusetts General Hospital Center for Regenerative Medicine and the

Cedars-Sinai opens new Induced Pluripotent Stem Cell Core Production Facility

The new facility will use the latest technology to generate induced pluripotent stem cells (iPS cells) from a patient's skin scraping. Such induced pluripotent stem cells can be replicated indefinitely and have biological properties similar to embryonic stem cells.   These “blank slate” cells can then be turned into any kind of differentiated cell, such as a brain cell or an eye cell or a liver cell.

“Opening the Cedars-Sinai Stem Cell Core Facility underscores what an exciting time this is in regenerative medicine," said Shlomo Melmed, MD, senior vice president of academic affairs and dean of the faculty at Cedars-Sinai.  “It also is an example of Cedars-Sinai’s deep commitment to the scientific research that will be translated into tomorrow’s leading-edge treatments.”

MRI-Based Technique Allows Non-Invasive Following Of Neural Stem Cells In Vivo

Legend once had it that once a brain cell dies, it’s lost forever. Neuroscientists now know that this is purely myth, having proved that the brain is constantly producing new neurons. These neural stem cells are born deep in an area of the brain called the subventricular zone. As time goes on, the cells, also called neuroblasts, make their way to other areas of the brain where they mature into functioning neurons.

Studying cells in a living brain is problematic. Common forms of in vivo cell imaging like fluorescence and bioluminescence rely on light to produce images, making them unsuitable for viewing neuroblasts buried deep beneath the skull and layers of opaque tissue. Until now, scientists had only been able to study neuronal stem cells by looking at slices of the brain under a microscope. Eric Ahrens, Professor of Biological Sciences at Carnegie Mellon University, was able to surmount this problem using MRI technology.

Rather than light, MRI uses magnets to create high-resolution images. A typical MRI scan uses a magnetic field and radio frequency pulses to cause the hydrogen protons found in the body’s water molecules to give off signals. Those signals are converted into a high-resolution image.

Research Demonstrates Bone Growth From Implanted Tooth And Dental Pulp Stem Cells

Stem cells derived from deciduous canine teeth and dental pulp can be grafted and produce bone regeneration between parents and offspring.

In the new research, deciduous teeth from canine puppies were extracted and then grafted onto parent canine mandibles as an allograft. After four weeks, bone defects were prepared on both sides of the host mandible. The newly formed bone was evaluated at two, four and eight weeks. When compared to controls, the study group demonstrated well-formed mature bone and neovascularization.

Mesoblast Partners With Lonza Group To Produce Off The Shelf Allogeneic Mesenchymal Precursor Stem Cell Therapies

Mesoblast Inc. is an Australian company (MSB.AX) that has had some success in clinical trials with its allogeneic mesenchymal precursor stem cell therapies. Mesoblast has a market capitalization of over 2 billion dollars and is entirely alone at that lofty level among stem cell companies. Geron, for example, has a current market capitalization of $282 million, while Osiris, which has a broad patent on mesenchymal stem cells from bone marrow, has a market capitalization of $171 million. Whether Osiris's patents and Mesoblast's are in conflict is unclear and is a question which may rise in the future of the two companies.

Mesoblast describes it's stem cell therapy technology platform as follows:

Researchers Turn Back the Clock on Adult Stem Cell Aging

As we age our body's ability to regenerate tissues and organs declines. The current stem cell hypothesis of aging suggests that living organisms, including we humans, are as old as their adult stem cells.

Now new research has shown the aging process for human adult stem cells -- those cells responsible for helping old or damaged tissues regenerate -- can be reversed.

The new research, accomplished by the Buck Institute for Research on Aging in collaboration with the Georgia Institute of Technology, pinpoints what is going wrong with the biological clock underlying the limited division of human adult stem cells as they age.

Dr. Gary Steinberg: Video Presentation Of Stem Cell Therapy For Stroke

Gary Steinberg, Stanford University, is a pioneer in stem cell research for stroke. This is a CIRM presentation that took place August 19 of 2010. Steinberg presents the subject broadly, touching on most of what has taken place and suggesting ideas of where we're headed in the stem cell therapy for stroke arena.

 

New Spinal Cord Stem Cell Discovered

Radial glial cells, marked by long projections that can forge through brain tissue, have not previously been found in an adult spinal cord.

Radial glia, which are instrumental in building the brain and spinal cord during an organism’s embryonic phase, vastly outnumber other potential stem cells in the spinal cord and are much more accessible.

The search for spinal stem cells of the central nervous system has until now focused deep in the spinal cord.

The Basics And Future Of Stem Cell Research: Amander Clark, UCLA

Amander Clark's laboratory uses embryonic stem cells as a model to study molecular events critical for human embryo development, with a special emphasis on the human germ line. She and her research team currently lead the effort at UCLA to generate new embryonic stem cell lines, with a major goal being the generation of clinic-grade lines for use in future therapeutics.

The video is Dr. Clark's UCLA Life Sciences Public Lecture delivered on March 16, 2011, and titled, "The Next Frontier in Stem Cell Research." It is an excellent summary of where we are and where were going.

 

Researchers Discover Method Of Removing Potential Tumor-Causing Stem Cells From Cells Developed For Use In Medical Treatments

Effective tricks for separating stem cells from other types are essential for many emerging medical treatments. These treatment approaches begin with researchers inducing stem cells to take specific forms, or differentiate, for instance into nerve cells. These differentiated cells might then be used to repair a spinal cord injury. Other cells might enable a diabetic's body to produce adequate insulin.

A key problem is that in the differentiation process, at least some stem cells inevitably remain in their undifferentiated, or pluripotent, state. These cells can grow to form tumors in patients if injected along with differentiated cells, a concern that has already led the US Food and Drug Administration (FDA) to delay clinical trials for promising stem cell-based therapies.

Neurosurgeons Use Adult Mesenchymal Stem Cells From Bone Marrow To Grow Neck Vertebrae

Removal of the cervical disc relieves pain by eliminating friction or compression between the vertebrae. Spinal fusion is used following surgery for degenerative disc disease, where the cusioning cartilage has worn away, leaving bone to rub agains bone and herniated discs, where the discs pinch or compress nerves.

Here, researchers used a new stem cell therapy to promote the growth of bone tissue following the removal of cervical discs -- the cushions between the bones in the neck -- to relieve chronic, debilitating pain.

Induced Pluripotent Stem Cells: Human Skin Cells Induced To Become Nuerons

In late May we posted about Stanford University research wherein human skin cells were converted directly into functional neurons in a period of four to five weeks with the addition of just four proteins.

In this recent research, Dr. Sheng Ding used two genes and a microRNA to convert a skin sample from a 55-year-old woman directly into brain cells. (MicroRNAs are tiny strands of genetic material that regulate almost every process in every cell of the body.) The cells created by Dr. Ding’s experiments exchanged the electrical impulses necessary for brain cells to communicate things such as thoughts and emotions. Using microRNA to reprogram cells is a safer and more efficient way than using the more common gene-modification approach. In ensuing experiments, Dr. Ding hopes to rely only on microRNAs and pharmaceutical compounds to convert skin cells to brain cells, which should lead to more efficient generation of cells for testing and regenerative purposes.