Researchers Discover Mechanism That Could Convert Certain Cells Into Insulin-Making Cells

Source: University of California - Los Angeles Health Sciences
Date: April 29, 2011

Summary:

Researchers from UCLA's Larry L. Hillblom Islet Research Center have taken an important step in that direction. They report in the April issue of the journal Developmental Cell that they may have discovered the underlying mechanism that could convert other cell types into pancreatic beta cells.

New Gene Therapy Technique on Induced Pluripotent Stem Cells Holds Promise in Treating Immune System Disease

Source: American Society of Hematology
Date: April 28, 2011

Summary:

Researchers have developed an effective technique that uses gene therapy on stem cells to correct chronic granulomatous disease (CGD) in cell culture, which could eventually serve as a treatment for this rare, inherited immune disorder, according to a new study published in Blood, the Journal of the American Society of Hematology.

After discovering that the disease could be reproduced in cell culture, the researchers then sought to correct the disease and produce healthy neutrophils in culture. They used synthetic proteins called zinc finger nucleases (ZFNs) to target a corrective gene at a specifically defined location in the genome of the X-CGD iPS cells. The iPS cells were then carefully screened to identify those containing a single copy of the corrective gene properly inserted only at the safe site. The researchers observed that some of the gene-corrected iPS cells could differentiate into neutrophils that produced normal levels of hydrogen peroxide, effectively "correcting" the disease.

Scientists create stable, self-renewing neural stem cells

Source: University of California - San Diego
Date: April 25, 2011

Summary:

In a paper published in the April 25 early online edition of the Proceedings of the National Academy of Sciences, researchers at the University of California, San Diego School of Medicine, the Gladstone Institutes in San Francisco and colleagues report a game-changing advance in stem cell science: the creation of long-term, self-renewing, primitive neural precursor cells from human embryonic stem cells (hESCs) that can be directed to become many types of neuron without increased risk of tumor formation.

Scientist makes key innovations in stem-cell technology

Source: Gladstone Institutes
Date: April 25, 2011

Summary:

SAN FRANCISCO, CA—A scientist at the Gladstone Institutes has made two significant stem-cell discoveries that advance medicine and human health by creating powerful new approaches for using stem cells and stem-cell-like technology.

In two papers being published on April 25 in the Proceedings of the National Academy of Sciences, Sheng Ding, PhD, reveals novel and safer methods not only for transforming embryonic stem cells into large numbers of brain cells with multiple uses, but also for transforming adult skin cells into so-called neural stem cells—cells that are just beginning to become brain cells. Dr. Ding last month joined Gladstone, a leading and independent biomedical-research organization, where he is expected to make a significant contribution to the institute's exemplary stem-cell research.

Enhanced cord blood stem cell transplants safe in long-term studies

Source: Dana-Farber Cancer Institute
Date: April 19, 2011

Summary:

An innovative experimental treatment for boosting the effectiveness of stem-cell transplants with umbilical cord blood has a favorable safety profile in long-term animal studies, report scientists from Dana-Farber Cancer Institute, Beth Israel Deaconess Medical Center (BIDMC), and Children's Hospital Boston (CHB).

Analysis of long-term safety testing in nonhuman primates, published online by the journal Cell Stem Cell, revealed that, after one year following transplant, umbilical cord blood units treated with a signaling molecule called 16,16-dimethyl PGE2 reconstituted all the normal types of blood cells, and none of the animals receiving treated cord blood units developed cancer.

Successful strategy developed to regenerate blood vessels

Source: University of Western Ontario
Date: April 18, 2011

Summary:

Researchers at the University of Western Ontario have discovered a way to stimulate the formation of highly functional new blood vessels. Scientists have developed a strategy in which a biological factor, called fibroblast growth factor 9 (FGF9), is delivered at the same time that the body is making its own effort at forming new blood vessels in vulnerable or damaged tissue.
Their findings are published online in Nature Biotechnology.

Patients' own cells yield new insights into the biology of schizophrenia

Source: Penn State University / Salk Institute for Biological Studies
Date: April 13, 2011

Summary:

A team of scientists at Penn State, the Salk Institute for Biological Studies, and other institutions have developed a method for recreating a schizophrenic patient's own brain cells, which then can be studied safely and effectively in a Petri dish. The method brings researchers a step closer to understanding the biological underpinnings of schizophrenia. The method also is expected to be used to study other mysterious diseases such as autism and bipolar disorder, and the researchers hope that it will open the door to personalized medicine -- customized treatments for individual sufferers of a disease based on genetic and cellular information.
The study will be published in a future edition of the journal Nature and will be posted on the journal's advance online website on April 13.

Principal Investigator, Presents Interim Safety Results for Neuralstem ALS Trial

Source: Neuralstem, Inc.
Date: April 12, 2011

Summary:

ROCKVILLE,MD PRNewswire via COMTEX/ -- Neuralstem, Inc. (NYSE Amex: CUR) announced that Eva Feldman, M.D., Ph.D., Principal Investigator of the Phase I safety trial of Neuralstem's human spinal cord stem cells (HSSC) in amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease), and unpaid Neuralstem consultant, presented interim safety data on the first nine patients. Dr. Feldman reported yesterday at the American Academy of Neurology (AAN American Academy of Neurology (AAN) Annual Meeting (http://www.aan.com/go/am11) that all nine ALS patients remain alive and that there were no unresolved serious adverse reactions related to surgery. Of the three ambulatory patients who were treated, all remain ambulatory with no serious adverse events secondary to surgery.

Scientists identify a surprising new source of cancer stem cells

Source: Whitehead Institute for Biomedical Research
Date: April 11, 2011

Summary:

CAMBRIDGE, Mass. – Whitehead Institute researchers have discovered that a differentiated cell type found in breast tissue can spontaneously convert to a stem-cell-like state, the first time such behavior has been observed in mammalian cells. These results refute scientific dogma, which states that differentiation is a one-way path; once cells specialize, they cannot return to the flexible stem-cell state on their own. This surprising finding, published online this week in the Proceedings of the National Academy of Sciences (PNAS), may have implications for the development of cancer therapeutics, particularly those aimed at eradicating cancer stem cells.

Gene find could aid nerve repair

Source: University of Edinburgh
Date: April 11, 2011

Summary:

Scientists have pinpointed a gene that controls how quickly a person’s nerves can regenerate after injury or disease.
Researchers at the University of Edinburgh say the find could lead to better understanding and treatment of conditions that affect the body’s nerves, such as motor neurone disease and carpal tunnel syndrome. Scientists say the discovery could also help to predict how quickly a person’s nerves will recover from a severe physical trauma, such as being involved in a car accident. In the long term, the research could help to develop more appropriate treatment programmes for those people who are likely to experience a slow recovery. The findings have been published in the journal Human Molecular Genetics.

‘Universal’ virus-free method turns blood cells to beating heart cells

Source: Johns Hopkins Medical Institutions
Date: April 11, 2011

Summary:

Johns Hopkins scientists have developed a simplified, cheaper, all-purpose method they say can be used by scientists around the globe to more safely turn blood cells into heart cells. The method is virus-free and produces heart cells that beat with nearly 100 percent efficiency, they claim.

To get stem cells taken from one source (such as blood) and develop them into a cell of another type (such as heart), scientists generally use viruses to deliver a package of genes into cells to first get them to turn into stem cells. However, viruses can mutate genes and initiate cancers in newly transformed cells. To insert the genes without using a virus, Zambidis’ team turned to plasmids, which are rings of DNA that replicate briefly inside cells and eventually degrade.

Adding to the complexity of coaxing stem cells into other cell types is the expensive and varied recipe of growth factors, nutrients and conditions that bathe stem cells during their transformation. The recipe of this “broth” differs from lab to lab and cell line to cell line.

Reporting in the April 8 issue of Public Library of Science ONE (PLoS ONE), Zambidis' team described what he called a "painstaking, two-year process" to simplify the recipe and environmental conditions that house cells undergoing transformation into heart cells. They found that their recipe worked consistently for at least 11 different stem cell lines tested and worked equally well for the more controversial embryonic stem cells, as well as stem cell lines generated from adult blood stem cells, their main focus.

Dopamine Controls Formation of New Brain Cells

Source: Karolinska Institutet
Date: 8 April 2011

Summary:

A study of the salamander brain has led researchers at Karolinska Institutet to discover a hitherto unknown function of the neurotransmitter dopamine. In an article published in the scientific journal Cell Stem Cell they show how in acting as a kind of switch for stem cells, dopamine controls the formation of new neurons in the adult brain. Their findings may one day contribute to new treatments for neurodegenerative diseases, such as Parkinson's.

The study was conducted using salamanders which unlike mammals recover fully from a Parkinson's-like condition within a four-week period. Parkinson's disease is a neurodegenerative disease characterised by the death of dopamine-producing cells in the mid-brain. As the salamander re-builds all lost dopamine-producing neurons, the researchers examined how the salamander brain detects the absence of these cells. This question is a fundamental one since it has not been known what causes the new formation of nerve cells and why the process ceases when the correct number have been made.

What they found out was that the salamander's stem cells are automatically activated when the dopamine concentration drops as a result of the death of dopamine-producing neurons, meaning that the neurotransmitter acts as a constant handbrake on stem cell activity.

Self-Made Eye: Formation of Optic Cup from Embryonic Stem Cells

Source: RIKEN Center for Developmental Biology
Date: April 7, 2011

Summary:

New research from the RIKEN Center for Developmental Biology shows how mouse stem cells spontaneously form into optic cups, the precursors of eyes. The research sheds light on the embryonic development of complex tissues. A breakthrough report describes how mouse embryonic stem cells (ESCs) are able to differentiate and assemble into an optic cup, capable of giving rise to a tissue exhibiting the stratified structure characteristic of the retina in vivo. Published in Nature, the study used a cutting-edge three-dimensional tissue culture system not only to demonstrate this self-organizing capacity of pluripotent stem cells, but the underlying cell dynamics as well.

New Highly Efficient Way to Make Reprogrammed Stem Cells

Source: University of Pennsylvania School of Medicine
Date: April 7, 2011

Summary:

PHILADELPHIA - Researchers at the University of Pennsylvania School of Medicine have devised a totally new and far more efficient way of generating induced pluripotent stem cells (iPSCs), immature cells that are able to develop into several different types of cells or tissues in the body. The researchers used fibroblast cells, which are easily obtained from skin biopsies, and could be used to generate patient-specific iPSCs for drug screening and tissue regeneration. The promise of this line of research is to one day efficiently generate patient-specific stem cells in order to study human disease as well as create a cellular "storehouse" to regenerate a person's own cells, for example heart or liver cells. Despite this promise, generation of iPSCs is hampered by low efficiency, especially when using human cells.

The study is published this week in Cell Stem Cell.

The self-made eye: Formation of optic cup from ES cells

Source: Riken Institute / Riken Cener for Developmental Biology
Date: April 7, 2011

Summary:

Developmental processes are increasingly well-characterized at the molecular and cell biological levels, but how more complex tissues and organs involving the coordinated action of multiple cell types in three dimensions is achieved remains something of a black box. One question of particular interest and importance is whether signaling interactions between neighboring tissues are essential to guiding organogenesis, or whether these can arise autonomously from developmental routines inherent to a given primordial tissue. Finding answers to these questions will be critical both to a better understanding of embryonic phenomena and to the ability to control the differentiation of cell populations into desired configurations.

In a breakthrough new report, RIKEN Cener for Developmental Biology researchers describe how mouse embryonic stem cells (ESCs) are able to differentiate and assemble into an optic cup, capable of giving rise to a tissue exhibiting the stratified structure characteristic of the retina in vivo. Published in Nature, the study used a cutting-edge three-dimensional tissue culture system not only to demonstrate this self-organizing capacity of pluripotent stem cells, but the underlying cell dynamics as well.

First patient to get stem cell therapy comes forward

Source: Washington Post
Posted: April 7, 2011 12:22 AM EDT

Summary:

The Washington Post reports a 21-year-old Alabama nursing student who was paralyzed from the chest down in a car crash in September has come forward to identify himself as the volunteer for a clinical trial using embryonic stem cells sponsored by Geron Corporation and conducted at the Shepherd Center in Atlanta.

Human Taste Cells Regenerate in a Dish

Source: Monell Chemical Senses Center
Date: April 6, 2011

Summary:

PHILADELPHIA – Following years of futile attempts, new research from the Monell Center demonstrates that living human taste cells can be maintained in culture for at least seven months. The findings provide scientists with a valuable tool to learn about the human sense of taste and how it functions in health and disease. This advance ultimately will assist efforts to prevent and treat taste loss or impairment due to infection, radiation, chemotherapy and chemical exposures.

Monell scientists first demonstrated in 2006 that taste cells from rats could successfully be maintained in culture. In the current study, published online in the journal Chemical Senses, they then applied that methodology to a more clinically relevant population -- humans.

Taking tiny samples of tongue tissue from human volunteers, the researchers first adapted existing techniques to demonstrate that the human taste cells indeed can regenerate in culture. They went on to show that the new taste cells were functional, maintaining key molecular and physiological properties characteristic of the parent cells. For example, the new cells also were activated by sweet and bitter taste molecules.

Human Taste Cells Regenerate in a Dish

Source: Monell Chemical Senses Center
Date: April 6, 2011

Summary:

Following years of futile attempts, new research from the Monell Center demonstrates that living human taste cells can be maintained in culture for at least seven months. The findings provide scientists with a valuable tool to learn about the human sense of taste and how it functions in health and disease. This advance ultimately will assist efforts to prevent and treat taste loss or impairment due to infection, radiation, chemotherapy and chemical exposures.

To dispel the long-held belief, the Monell scientists first demonstrated in 2006 that taste cells from rats could successfully be maintained in culture. In the current study, published online in the journal Chemical Senses, they then applied that methodology to a more clinically relevant population -- humans. Taking tiny samples of tongue tissue from human volunteers, the researchers first adapted existing techniques to demonstrate that the human taste cells indeed can regenerate in culture. They went on to show that the new taste cells were functional, maintaining key molecular and physiological properties characteristic of the parent cells. For example, the new cells also were activated by sweet and bitter taste molecules.

Scientists make skin repair discovery: Bone Marrow Cells That Transform Into Skin Cells Could Revolutionize Approach to Wound Treatment

Source: King's College London
Date: 5 April 2011

Summary:

Researchers at King's College London and Osaka University in Japan have identified specific bone marrow cells that can transform into skin cells to repair damaged skin tissue, according to a study published in Proceedings of the National Academy of Sciences. The team has uncovered how this process works, providing new insights into the mechanisms behind skin repair. This significant advance has the potential to revolutionise approaches to wound treatment in the future, which could benefit people with chronic wounds such as leg ulcers, pressure sores and burns, as well as genetic skin diseases such as epidermolysis bullosa, which causes painful blisters on the skin.

Patient's Own Cells May Hold Therapeutic Promise After Reprogramming, Gene Correction

Source: University of Wisconsin-Madison
Date: April 4, 2011

Summary:

Scientists from the Morgridge Institute for Research, the University of Wisconsin-Madison, the University of California and the WiCell Research Institute moved gene therapy one step closer to clinical reality by determining that the process of correcting a genetic defect does not substantially increase the number of potentially cancer-causing mutations in induced pluripotent stem cells.

Their work, scheduled for publication the week of April 4 in the online edition of the journal Proceedings of the National Academy of Sciences and funded by a Wynn-Gund Translational Award from the Foundation Fighting Blindness, suggests that human induced pluripotent stem cells altered to correct a genetic defect may be cultured into subsequent generations of cells that remain free of the initial disease. However, although the gene correction itself does not increase the instability or the number of observed mutations in the cells, the study reinforced other recent findings that induced pluripotent stem cells themselves carry a significant number of genetic mutations.

In the study, the researchers used a technique called episomal reprogramming to generate the induced pluripotent stem cells. In contrast to techniques that use retroviruses, episomal reprogramming doesn't involve inserting DNA into the genome. This technique allowed them to produce cells that were free of potentially harmful transgene sequences.

The scientists then corrected the actual retinal disease-causing gene defect using a technique called homologous recombination. The stem cells were extensively "characterized" or studied before and after the process to assess whether they developed significant additional mutations or variations. The results showed that the culture conditions required to correct a genetic defect did not substantially increase the number of mutations.

Newly discovered epigenetic tag offers insight into embryonic stem cell regulation

Source: Biotechnology and Biological Sciences Research Council
Date: 4 April 2011

Summary:

Scientists from the Babraham Institute have gained a new understanding of how molecular signals and switches control how an embryo develops into an adult. The new research, published today (3 April) in the journal Nature, details how a newly discovered form of epigenetic regulation controls the development of embryonic stem (ES) cells.

The research, funded by BBSRC, MRC, the University of Cambridge and EPIGENOME, has important implications for regenerative medicine as it could offer new methods for controlling how ES cells differentiate in every cell in the human body and, potentially, to the growing field of induced pluripotent stem (iPS) cells where adult stem cell are 'reprogrammed'.

Embryonic stem (ES) cells are pluripotent cells present in the early embryo, which have the capacity to differentiate into all the specialised cells that make up the adult body. As an embryo develops, the cells respond to signals and differentiate to acquire a particular fate, for example a skin cell. Cell fate is governed not only by the genome, but also by chemical changes to DNA that alter the DNA structure but not its sequence. These 'epigenetic' tags are one of the ways that genes get switched on or off in different places at different times, enabling different tissues and organs to arise from a single fertilised egg and also helps to explain how our genes can be influenced by the environment.

The new research reveals that a new type of epigenetic modification, 5-hydroxymethylcytosine (5hmC), plays a critical role mediating the external signals that instruct a cell how to develop; this tiny chemical tag (5hmC) is attached to or removed from the genetic sequence depending on the message received, switching genes on or off. The researchers managed to identify the location of this tag throughout the genome, using high throughput sequencing methods. They observed for so called pluripotency-related genes that, as 5hmC decreases, another previously known epigenetic modification, 5-methylcytosine (5mC) increases - this shift has consequences in determining how genes function and hence a cell's developmental fate.

Why stem cells don’t just want to make neurons

Source: Biotechnology and Biological Sciences Research Council
Date: 1 April 2011

Summary:

Research being presented at the UK National Stem Cell Network annual science conference provides another piece in the puzzle of why it can be so hard to produce large numbers of the same type of cell in the lab -- a process that is vital for scaling up stem cell production for therapeutic use. This knowledge will help researchers to develop strategies for obtaining the desired cell type for use in either research or medicine.

The work will be presented by Dr Robert Kelsh from the University of Bath and was funded in part by the Biotechnology and Biological Sciences Research Council (BBSRC). It shows for the first time that a gene called Sox10 coordinates a vital part of healthy development: once a stem cell has committed to becoming a neuron it sends out a signal telling surrounding cells to become something else -- a characteristic that certainly hinders making pure samples of these cells for therapies.