stemcellsGIVElife Blog
Stem Cell Basics
Introduction
What are the unique properties of all stem cells?
What are embryonic stem cells?
What are adult stem cells?
What are the similarities and differences between embryonic and adult stem cells?
What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?
Where can I get more information?
VI. What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?
There are many ways in which human stem cells can be used in basic research and in clinical research. However, there are many technical hurdles between the promise of stem cells and the realization of these uses, which will only be overcome by continued intensive stem cell research.
Studies of human embryonic stem cells may yield information about the complex events that occur during human development. A primary goal of this work is to identify how undifferentiated stem cells become differentiated. Scientists know that turning genes on and off is central to this process. Some of the most serious medical conditions, such as cancer and birth defects, are due to abnormal cell division and differentiation. A better understanding of the genetic and molecular controls of these processes may yield information about how such diseases arise and suggest new strategies for therapy. A significant hurdle to this use and most uses of stem cells is that scientists do not yet fully understand the signals that turn specific genes on and off to influence the differentiation of the stem cell.
Human stem cells could also be used to test new drugs. For example, new medications could be tested for safety on differentiated cells generated from human pluripotent cell lines. Other kinds of cell lines are already used in this way. Cancer cell lines, for example, are used to screen potential anti-tumor drugs. But, the availability of pluripotent stem cells would allow drug testing in a wider range of cell types. However, to screen drugs effectively, the conditions must be identical when comparing different drugs. Therefore, scientists will have to be able to precisely control the differentiation of stem cells into the specific cell type on which drugs will be tested. Current knowledge of the signals controlling differentiation fall well short of being able to mimic these conditions precisely to consistently have identical differentiated cells for each drug being tested.
Perhaps the most important potential application of human stem cells is the generation of cells and tissues that could be used for cell-based therapies. Today, donated organs and tissues are often used to replace ailing or destroyed tissue, but the need for transplantable tissues and organs far outweighs the available supply. Stem cells, directed to differentiate into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat diseases including Parkinson's and Alzheimer's diseases, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis.
Figure 4. Heart muscle repair with adult stem cells. Click here for larger image.
For example, it may become possible to generate healthy heart muscle cells in the laboratory and then transplant those cells into patients with chronic heart disease. Preliminary research in mice and other animals indicates that bone marrow stem cells, transplanted into a damaged heart, can generate heart muscle cells and successfully repopulate the heart tissue. Other recent studies in cell culture systems indicate that it may be possible to direct the differentiation of embryonic stem cells or adult bone marrow cells into heart muscle cells (Figure 4).
In people who suffer from type I diabetes, the cells of the pancreas that normally produce insulin are destroyed by the patient's own immune system. New studies indicate that it may be possible to direct the differentiation of human embryonic stem cells in cell culture to form insulin-producing cells that eventually could be used in transplantation therapy for diabetics.
To realize the promise of novel cell-based therapies for such pervasive and debilitating diseases, scientists must be able to easily and reproducibly manipulate stem cells so that they possess the necessary characteristics for successful differentiation, transplantation and engraftment. The following is a list of steps in successful cell-based treatments that scientists will have to learn to precisely control to bring such treatments to the clinic. To be useful for transplant purposes, stem cells must be reproducibly made to:
Proliferate extensively and generate sufficient quantities of tissue.
Differentiate into the desired cell type(s).
Survive in the recipient after transplant.
Integrate into the surrounding tissue after transplant.
Function appropriately for the duration of the recipient's life.
Avoid harming the recipient in any way.
Also, to avoid the problem of immune rejection, scientists are experimenting with different research strategies to generate tissues that will not be rejected.
To summarize, the promise of stem cell therapies is an exciting one, but significant technical hurdles remain that will only be overcome through years of intensive research.
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STEMCELLSgiveLIFE: A PLACE TO LEARN!
STEMCELLSgiveLIFE: A PLACE TO LEARN!
To many, it is one of the most exciting developments in modern
medicine. To others, it is an ethically unacceptable practice. The
conflict of beliefs has always meant that the use of stem cells from
human embryos to treat a range of debilitating and incurable disorders
has remained controversial.
Now scientists have made a breakthrough that could offer a medical
solution without the controversy, by undermining the case for using
embryonic stem cells at all.
New evidence suggests that cells derived from a patient's own bone
marrow may regenerate damaged nerves in the brain, a task once
considered impossible. It is an important breakthrough in the
treatment of illnesses such as Parkinson's, multiple sclerosis and
Alzheimer's disease. brain INJURY
The work has potential to challenge embryonic stem cell research
because these stem cells have come not from embryos but from the bone
marrow of a mature adult.
It is the latest evidence to emerge from several lines of research
that have pointed to the power of adult stem cells to "reinvent"
themselves rather than to be narrowly predestined to develop into just
one type of body tissue.
The findings, published in the journal Cell Transplantation, will
reopen the debate over the ethics of experimenting on stem cells taken
from human embryos given that adult stem cells appear to possess the
same all-round ability to develop into specialised tissues.
Anti-abortion groups and the Vatican have fiercely opposed the use of
human embryos in stem cell research.
Stem cells have become one of the most exciting areas of medical
research because of their ability to be cultured in the laboratory and
stimulated with chemicals to become any one of the scores of
specialised tissues of the body.
Scientists envisage a day when stem cells can be used to repair
damaged organs rather than using potentially toxic drugs, a transplant
or palliative care for the terminally ill.
Several sources of stem cells have been identified, such as "spare"
IVF embryos less than 14 days old or adult bone marrow that is
constantly regenerating to produce fresh blood cells. The question has
been whether adult stem cells are just as good as embryonic stem cells
in terms of "pluripotency" the ability of a cell to become any
specialised cell of the body.
Work on animals shows the power of cultured embryonic stem cells to
develop into any tissue, but adult stem cells were traditionally
thought to be more fixed in terms of what they could become bone
marrow should only develop into blood cells for instance. But the
latest research, led by Walter Low, professor of neurosurgery at the
University of Minnesota Medical School, shows bone marrow extracted
from adult mice can develop into fully functioning, specialised brain
cells.
Professor Low injected bone marrow cells from a mouse into early
embryos, which were implanted into other mice who gave birth to live
young. The offspring were found to have taken up the "foreign" bone
marrow stem cells and used them to make cells in all regions of the
brain.
The transplanted stem cells developed into nerve cells, which normally
conduct electrical impulses, glial cells, which provide support to the
nerve cells, and cells that produce the fatty myelin sheath around the
nerve cells, which is damaged in patients with multiple sclerosis.
Catherine Verfaillie, a colleague of Professor Low, said the bone
marrow stem cells developed into all the cells known to be implicated
in Parkinson's disease, Huntington's disease, ataxia and Alzheimer's
disease. "This tells us that these adult stem cells are capable of
becoming nerve cells that communicate with other nerve cells within
the brain and form proper neural circuits that permit the mice to
function normally," Dr Verfaillie said.
A number of studies have already indicated that adult bone marrow
cells may have the ability to develop into non-blood tissue.
Scientists from the US National Institute of Neurological Diseases and
Stroke in Bethesda, Maryland, found for instance that post-mortem
tests on women who had received bone marrow transplants from men
possessed brain cells containing the male Y chromosome. The
implications were that male bone marrow stem cells had migrated to the
women's brains to become nerve cells, said Eva Mezey, who led the
study. "We have had trouble convincing some members of the scientific
community that this could happen," Dr Mezey said.
Opponents of the use of human embryos in stem cell research are likely
to use the findings to support their belief that there is no real need
to experiment with human embryos.
Josephine Quintavalle, a lawyer and campaigner, said that she would
use the latest work on adult cells to challenge whether scientists
needed to use human embryos at all. "Adult stem cells are infinitely
better than embryonic stem cells," she said. "The bias in the UK has
been to use embryonic stem cells simply because we have the most
permissive environment in the world for this sort of research."
Many British scientists and scientific organisations such as the
Royal Society believe research on both adult and embryonic stem
cells needs to be done in parallel before any decisions are taken to
ban the latter.
A report on stem cells by a House of Lords committee concluded: "It is
unlikely that either adult stem cells or embryonic stem cells alone
will provide the basis for all stem cell-based therapies; it is
therefore necessary to keep both routes to therapy open to ensure
maximum medical benefit."
Professor Low said further work was needed to ensure that the adult
stem cells in his study were genuinely developing into specialised
brain cells rather than merely fusing with them.
Professor Austin Smith, of Edinburgh University, found evidence to
suggest that adult stem cells tended to fuse with other cells, which
could make them potentially cancerous.
"This suggests a need for caution with regard to the therapeutic use
of adult tissue stem cells. If they only make other tissues by fusing
with existing cells rather than producing new cells, their utility for
tissue repair and regenerative medicine will be greatly reduced,"
Professor Smith said.
"If nothing else, our study indicates that calls for a halt to
embryonic stem cell research are not scientifically justified," he
added.
Professor Low said his findings were unlikely to be the result of
adult stem cells fusing with existing cells but he could not yet
rule it out.
Further research this year should establish beyond doubt whether adult
stem cells are truly capable of regenerating damaged brains, he said.
Until then, he added, further work on embryonic stem cells and adult
bone marrow cells was still necessary to compare the remarkable
attributes of both types of cell
medicine. To others, it is an ethically unacceptable practice. The
conflict of beliefs has always meant that the use of stem cells from
human embryos to treat a range of debilitating and incurable disorders
has remained controversial.
Now scientists have made a breakthrough that could offer a medical
solution without the controversy, by undermining the case for using
embryonic stem cells at all.
New evidence suggests that cells derived from a patient's own bone
marrow may regenerate damaged nerves in the brain, a task once
considered impossible. It is an important breakthrough in the
treatment of illnesses such as Parkinson's, multiple sclerosis and
Alzheimer's disease. brain INJURY
The work has potential to challenge embryonic stem cell research
because these stem cells have come not from embryos but from the bone
marrow of a mature adult.
It is the latest evidence to emerge from several lines of research
that have pointed to the power of adult stem cells to "reinvent"
themselves rather than to be narrowly predestined to develop into just
one type of body tissue.
The findings, published in the journal Cell Transplantation, will
reopen the debate over the ethics of experimenting on stem cells taken
from human embryos given that adult stem cells appear to possess the
same all-round ability to develop into specialised tissues.
Anti-abortion groups and the Vatican have fiercely opposed the use of
human embryos in stem cell research.
Stem cells have become one of the most exciting areas of medical
research because of their ability to be cultured in the laboratory and
stimulated with chemicals to become any one of the scores of
specialised tissues of the body.
Scientists envisage a day when stem cells can be used to repair
damaged organs rather than using potentially toxic drugs, a transplant
or palliative care for the terminally ill.
Several sources of stem cells have been identified, such as "spare"
IVF embryos less than 14 days old or adult bone marrow that is
constantly regenerating to produce fresh blood cells. The question has
been whether adult stem cells are just as good as embryonic stem cells
in terms of "pluripotency" the ability of a cell to become any
specialised cell of the body.
Work on animals shows the power of cultured embryonic stem cells to
develop into any tissue, but adult stem cells were traditionally
thought to be more fixed in terms of what they could become bone
marrow should only develop into blood cells for instance. But the
latest research, led by Walter Low, professor of neurosurgery at the
University of Minnesota Medical School, shows bone marrow extracted
from adult mice can develop into fully functioning, specialised brain
cells.
Professor Low injected bone marrow cells from a mouse into early
embryos, which were implanted into other mice who gave birth to live
young. The offspring were found to have taken up the "foreign" bone
marrow stem cells and used them to make cells in all regions of the
brain.
The transplanted stem cells developed into nerve cells, which normally
conduct electrical impulses, glial cells, which provide support to the
nerve cells, and cells that produce the fatty myelin sheath around the
nerve cells, which is damaged in patients with multiple sclerosis.
Catherine Verfaillie, a colleague of Professor Low, said the bone
marrow stem cells developed into all the cells known to be implicated
in Parkinson's disease, Huntington's disease, ataxia and Alzheimer's
disease. "This tells us that these adult stem cells are capable of
becoming nerve cells that communicate with other nerve cells within
the brain and form proper neural circuits that permit the mice to
function normally," Dr Verfaillie said.
A number of studies have already indicated that adult bone marrow
cells may have the ability to develop into non-blood tissue.
Scientists from the US National Institute of Neurological Diseases and
Stroke in Bethesda, Maryland, found for instance that post-mortem
tests on women who had received bone marrow transplants from men
possessed brain cells containing the male Y chromosome. The
implications were that male bone marrow stem cells had migrated to the
women's brains to become nerve cells, said Eva Mezey, who led the
study. "We have had trouble convincing some members of the scientific
community that this could happen," Dr Mezey said.
Opponents of the use of human embryos in stem cell research are likely
to use the findings to support their belief that there is no real need
to experiment with human embryos.
Josephine Quintavalle, a lawyer and campaigner, said that she would
use the latest work on adult cells to challenge whether scientists
needed to use human embryos at all. "Adult stem cells are infinitely
better than embryonic stem cells," she said. "The bias in the UK has
been to use embryonic stem cells simply because we have the most
permissive environment in the world for this sort of research."
Many British scientists and scientific organisations such as the
Royal Society believe research on both adult and embryonic stem
cells needs to be done in parallel before any decisions are taken to
ban the latter.
A report on stem cells by a House of Lords committee concluded: "It is
unlikely that either adult stem cells or embryonic stem cells alone
will provide the basis for all stem cell-based therapies; it is
therefore necessary to keep both routes to therapy open to ensure
maximum medical benefit."
Professor Low said further work was needed to ensure that the adult
stem cells in his study were genuinely developing into specialised
brain cells rather than merely fusing with them.
Professor Austin Smith, of Edinburgh University, found evidence to
suggest that adult stem cells tended to fuse with other cells, which
could make them potentially cancerous.
"This suggests a need for caution with regard to the therapeutic use
of adult tissue stem cells. If they only make other tissues by fusing
with existing cells rather than producing new cells, their utility for
tissue repair and regenerative medicine will be greatly reduced,"
Professor Smith said.
"If nothing else, our study indicates that calls for a halt to
embryonic stem cell research are not scientifically justified," he
added.
Professor Low said his findings were unlikely to be the result of
adult stem cells fusing with existing cells but he could not yet
rule it out.
Further research this year should establish beyond doubt whether adult
stem cells are truly capable of regenerating damaged brains, he said.
Until then, he added, further work on embryonic stem cells and adult
bone marrow cells was still necessary to compare the remarkable
attributes of both types of cell
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http://www.americansforcures.org/
Stem cells are unprogrammed cells in the human body that can be
described as "shape shifters." These cells have the ability to
change into other types of cells. Stem cells are at the center of a
new field of science called regenerative medicine. Because stem
cells can become bone, muscle, cartilage and other specialized types
of cells, they have the potential to treat many diseases, including
Parkinson's, Alzheimer's, diabetes and cancer. Eventually, they may
also be used to regenerate organs, reducing the need for organ
transplants and related surgeries.
"Stem cells are like little kids who, when they grow up, can enter a
variety of professions," Dr. Marc Hedrick of the UCLA School of
Medicine says. "A child might become a fireman, a doctor or a
plumber, depending on the influences in their life -- or
environment. In the same way, these stem cells can become many
tissues by making certain changes in their environment."
Stem cells can typically be broken into four types:
Embryonic stem cells - Stem cells taken from human embryos
Fetal stem cells- Stem cells taken from aborted fetal tissue
Umbilical stem cells - Stem cells take from umbilical cords
Adult stem cells - Stem cells taken from adult tissue
Embryonic and fetal stem cells have the potential to morph into a
greater variety of cells than adult stem cells do.
In April 2001, researchers at UCLA and the University of Pittsburgh
found stem cells in fat sucked out of liposuction patients.
Previously, stem cells were found only in bone marrow, brain tissue
and fetal tissue -- sources that have caused both logistical and
ethical problems. Stem cells from fat have the ability to mature
into other types of specific cells, including muscle, bone and
cartilage, but how many other types is still unknown.
Prior to being transplanted into a person's tissue to begin
regeneration of that tissue, stem cells have to go through
differentiation. Differentiation is the process by which scientists
pre-specialize the stem cells, almost like preprogramming the stem
cells to become specific cells. These cells are then injected into
the area of the body being targeted for tissue regeneration. When
stem cells come into contact with growth chemicals in the body, the
chemicals program the stem cells to grow into the tissue surrounding
it.
Stem cells are already being used to treat leukemia and some joint
repairs. For example, a bone-marrow transplant is accomplished by
injecting stem cells from a donor into the bloodstream of the
patient. Stem cells from bone marrow also have the ability to repair
the liver. Researchers are studying stem cells to find out if they
could correct brain damage resulting from Parkinson's disease.
The next step will be to learn what influences stem cells to change
into particular types of cells. Once that's known, it will be
possible to grow cells that perfectly match those of the patients.
stem cells ARE life!
PEACE.OUT ;)-
described as "shape shifters." These cells have the ability to
change into other types of cells. Stem cells are at the center of a
new field of science called regenerative medicine. Because stem
cells can become bone, muscle, cartilage and other specialized types
of cells, they have the potential to treat many diseases, including
Parkinson's, Alzheimer's, diabetes and cancer. Eventually, they may
also be used to regenerate organs, reducing the need for organ
transplants and related surgeries.
"Stem cells are like little kids who, when they grow up, can enter a
variety of professions," Dr. Marc Hedrick of the UCLA School of
Medicine says. "A child might become a fireman, a doctor or a
plumber, depending on the influences in their life -- or
environment. In the same way, these stem cells can become many
tissues by making certain changes in their environment."
Stem cells can typically be broken into four types:
Embryonic stem cells - Stem cells taken from human embryos
Fetal stem cells- Stem cells taken from aborted fetal tissue
Umbilical stem cells - Stem cells take from umbilical cords
Adult stem cells - Stem cells taken from adult tissue
Embryonic and fetal stem cells have the potential to morph into a
greater variety of cells than adult stem cells do.
In April 2001, researchers at UCLA and the University of Pittsburgh
found stem cells in fat sucked out of liposuction patients.
Previously, stem cells were found only in bone marrow, brain tissue
and fetal tissue -- sources that have caused both logistical and
ethical problems. Stem cells from fat have the ability to mature
into other types of specific cells, including muscle, bone and
cartilage, but how many other types is still unknown.
Prior to being transplanted into a person's tissue to begin
regeneration of that tissue, stem cells have to go through
differentiation. Differentiation is the process by which scientists
pre-specialize the stem cells, almost like preprogramming the stem
cells to become specific cells. These cells are then injected into
the area of the body being targeted for tissue regeneration. When
stem cells come into contact with growth chemicals in the body, the
chemicals program the stem cells to grow into the tissue surrounding
it.
Stem cells are already being used to treat leukemia and some joint
repairs. For example, a bone-marrow transplant is accomplished by
injecting stem cells from a donor into the bloodstream of the
patient. Stem cells from bone marrow also have the ability to repair
the liver. Researchers are studying stem cells to find out if they
could correct brain damage resulting from Parkinson's disease.
The next step will be to learn what influences stem cells to change
into particular types of cells. Once that's known, it will be
possible to grow cells that perfectly match those of the patients.
stem cells ARE life!
PEACE.OUT ;)-
Like bone marrow, cord blood is enriched with stem cells, the building blocks of blood and the immune system. Stem cells differentiate, or reproduce, into other cells: red blood cells, which carry oxygen throughout the body; white blood cells, which fight infections; and platelets, which are necessary for clotting. Stem cells from cord blood are used to treat a variety of cancer and blood diseases. Read More »
Steve Stice, who has dedicated his research using embryonic stem cells to improving the lives of people with degenerative diseases and debilitating injuries, newly has discovered the process to produce billions of neural cells from a few stem cells, could now aid in national security.
In collaboration with the U.S. Naval Research Laboratory, Stice hopes to use his recently developed neural cell kits to detect chemical threats.
Steve Stice, a University of Georgia animal science professor and Georgia Research Alliance eminent scholar in the UGA College of Agricultural and Environmental Sciences said that they have a device that looks like a small tool box that contains neural cells and can detect changes in their electrical activity, when these cells' activity is altered, there's something present that shouldn't be and they don't like it.
Stice's neural cell kits created from human embryonic stem cell lines last up to six months. "We've never tested to see how far beyond that they're viable," he said. "It could be much longer."
He has contacted researchers at NRL who had published a paper on the detection system. He said that they've developed the recording device, and they have the cells they need. So working together, they can vastly improve that project.
Stice explained the device. "The monitoring system records electrical activity in the neural cells, which are usually in a set, rhythmic pattern," he said, drawing a chart that looks like a pattern on a heart monitor.
The researchers got support for the project from several congressmen, including Sen. Johnny Isakson and Georgia Rep. Jack Kingston.
The current system can detect an agent but it can't identify it. "We may be able to further develop the system so that for some chemicals there are signatures that will lead to a future way to rapidly identify exactly what the chemical is," Stice said.
"Noncell systems available now can detect specified chemicals," he said. "But this is a broader detection system that will be more valuable because we don't know what terrorists will hit us with."
Stice feels this detection system is important to troops and civilians. "There's always a concern for nerve agents and unintentional effects of warfare where troops are in the way of chemical agents," he said.
Stem Cell Scientists Found a Way to Fight AIDS
Further Grants from California Stem Cell Agency Will be a Booster for Embryonic Stem Cell Research
Nerve Cell Transplants may Help Fight Multiple Sclerosis
Human Muscle stem cells fight incontinence
Lawmakers Should Back Up Stem Cell Therapy to Fight Deadly Diseases
Stem Cell That Directly Determines Fate of its Daughters
Development of First Generation Stem Cell Therapies
Stem Cells Join The Fight Against AIDS
Embryonic Stem Cell Therapy is a Real Hope for Those Who are Suffering form Deadly Incurable Diseases
Children's Cord Blood is a Form of Biological Insurance
In collaboration with the U.S. Naval Research Laboratory, Stice hopes to use his recently developed neural cell kits to detect chemical threats.
Steve Stice, a University of Georgia animal science professor and Georgia Research Alliance eminent scholar in the UGA College of Agricultural and Environmental Sciences said that they have a device that looks like a small tool box that contains neural cells and can detect changes in their electrical activity, when these cells' activity is altered, there's something present that shouldn't be and they don't like it.
Stice's neural cell kits created from human embryonic stem cell lines last up to six months. "We've never tested to see how far beyond that they're viable," he said. "It could be much longer."
He has contacted researchers at NRL who had published a paper on the detection system. He said that they've developed the recording device, and they have the cells they need. So working together, they can vastly improve that project.
Stice explained the device. "The monitoring system records electrical activity in the neural cells, which are usually in a set, rhythmic pattern," he said, drawing a chart that looks like a pattern on a heart monitor.
The researchers got support for the project from several congressmen, including Sen. Johnny Isakson and Georgia Rep. Jack Kingston.
The current system can detect an agent but it can't identify it. "We may be able to further develop the system so that for some chemicals there are signatures that will lead to a future way to rapidly identify exactly what the chemical is," Stice said.
"Noncell systems available now can detect specified chemicals," he said. "But this is a broader detection system that will be more valuable because we don't know what terrorists will hit us with."
Stice feels this detection system is important to troops and civilians. "There's always a concern for nerve agents and unintentional effects of warfare where troops are in the way of chemical agents," he said.
Stem Cell Scientists Found a Way to Fight AIDS
Further Grants from California Stem Cell Agency Will be a Booster for Embryonic Stem Cell Research
Nerve Cell Transplants may Help Fight Multiple Sclerosis
Human Muscle stem cells fight incontinence
Lawmakers Should Back Up Stem Cell Therapy to Fight Deadly Diseases
Stem Cell That Directly Determines Fate of its Daughters
Development of First Generation Stem Cell Therapies
Stem Cells Join The Fight Against AIDS
Embryonic Stem Cell Therapy is a Real Hope for Those Who are Suffering form Deadly Incurable Diseases
Children's Cord Blood is a Form of Biological Insurance
What are the unique properties of all stem cells?
What are embryonic stem cells?
What are adult stem cells?
What are the similarities and differences between embryonic and adult stem cells?
What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?
Where can I get more information?
I. Introduction
Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine.
Stem cells are one of the most fascinating areas of biology today. But like many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates new discoveries.
The NIH developed this primer to help readers understand the answers to questions such as: What are stem cells? What different types of stem cells are there and where do they come from? What is the potential for new medical treatments using stem cells? What research is needed to make such treatments a reality?
A. What are stem cells and why are they important?
Stem Cells for the Future Treatment
of Parkinson's Disease
Parkinson's disease (PD) is a very common neurodegenerative disorder that affects more than 2% of the population over 65 years of age. PD is caused by a progressive degeneration and loss of dopamine (DA)-producing neurons, which leads to tremor, rigidity, and hypokinesia (abnormally decreased mobility). It is thought that PD may be the first disease to be amenable to treatment using stem cell transplantation. Factors that support this notion include the knowledge of the specific cell type (DA neurons) needed to relieve the symptoms of the disease. In addition, several laboratories have been successful in developing methods to induce embryonic stem cells to differentiate into cells with many of the functions of DA neurons.
In a recent study, scientists directed mouse embryonic stem cells to differentiate into DA neurons by introducing the gene Nurr1. When transplanted into the brains of a rat model of PD, these stem cell-derived DA neurons reinnervated the brains of the rat Parkinson model, released dopamine and improved motor function.
Regarding human stem cell therapy, scientists are developing a number of strategies for producing dopamine neurons from human stem cells in the laboratory for transplantation into humans with Parkinson's disease. The successful generation of an unlimited supply of dopamine neurons could make neurotransplantation widely available for Parkinson's patients at some point in the future.
Stem cells have two important characteristics that distinguish them from other types of cells. First, they are unspecialized cells that renew themselves for long periods through cell division. The second is that under certain physiologic or experimental conditions, they can be induced to become cells with special functions such as the beating cells of the heart muscle or the insulin-producing cells of the pancreas.
Scientists primarily work with two kinds of stem cells from animals and humans: embryonic stem cells and adult stem cells, which have different functions and characteristics that will be explained in this document. Scientists discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery, in 1998, of how to isolate stem cells from human embryos and grow the cells in the laboratory. These are called human embryonic stem cells. The embryos used in these studies were created for infertility purposes through in vitro fertilization procedures and when they were no longer needed for that purpose, they were donated for research with the informed consent of the donor.
Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, stem cells in developing tissues give rise to the multiple specialized cell types that make up the heart, lung, skin, and other tissues. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease.
It has been hypothesized by scientists that stem cells may, at some point in the future, become the basis for treating diseases such as Parkinson's disease, diabetes, and heart disease.
Scientists want to study stem cells in the laboratory so they can learn about their essential properties and what makes them different from specialized cell types. As scientists learn more about stem cells, it may become possible to use the cells not just in cell-based therapies, but also for screening new drugs and toxins and understanding birth defects. However, as mentioned above, human embryonic stem cells have only been studied since 1998. Therefore, in order to develop such treatments scientists are intensively studying the fundamental properties of stem cells, which include:
determining precisely how stem cells remain unspecialized and self renewing for many years; and
identifying the signals that cause stem cells to become specialized cells.
B. Scope of this document
This primer on stem cells is intended for anyone who wishes to learn more about the biological properties of stem cells, the important questions about stem cells that are the focus of scientific research, and the potential use of stem cells in research and in treating disease. The primer includes information about stem cells derived from the embryo and adult. Much of the information included here is about stem cells derived from human tissues, but some studies of animal-derived stem cells are also described.
What are embryonic stem cells?
What are adult stem cells?
What are the similarities and differences between embryonic and adult stem cells?
What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?
Where can I get more information?
I. Introduction
Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine.
Stem cells are one of the most fascinating areas of biology today. But like many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates new discoveries.
The NIH developed this primer to help readers understand the answers to questions such as: What are stem cells? What different types of stem cells are there and where do they come from? What is the potential for new medical treatments using stem cells? What research is needed to make such treatments a reality?
A. What are stem cells and why are they important?
Stem Cells for the Future Treatment
of Parkinson's Disease
Parkinson's disease (PD) is a very common neurodegenerative disorder that affects more than 2% of the population over 65 years of age. PD is caused by a progressive degeneration and loss of dopamine (DA)-producing neurons, which leads to tremor, rigidity, and hypokinesia (abnormally decreased mobility). It is thought that PD may be the first disease to be amenable to treatment using stem cell transplantation. Factors that support this notion include the knowledge of the specific cell type (DA neurons) needed to relieve the symptoms of the disease. In addition, several laboratories have been successful in developing methods to induce embryonic stem cells to differentiate into cells with many of the functions of DA neurons.
In a recent study, scientists directed mouse embryonic stem cells to differentiate into DA neurons by introducing the gene Nurr1. When transplanted into the brains of a rat model of PD, these stem cell-derived DA neurons reinnervated the brains of the rat Parkinson model, released dopamine and improved motor function.
Regarding human stem cell therapy, scientists are developing a number of strategies for producing dopamine neurons from human stem cells in the laboratory for transplantation into humans with Parkinson's disease. The successful generation of an unlimited supply of dopamine neurons could make neurotransplantation widely available for Parkinson's patients at some point in the future.
Stem cells have two important characteristics that distinguish them from other types of cells. First, they are unspecialized cells that renew themselves for long periods through cell division. The second is that under certain physiologic or experimental conditions, they can be induced to become cells with special functions such as the beating cells of the heart muscle or the insulin-producing cells of the pancreas.
Scientists primarily work with two kinds of stem cells from animals and humans: embryonic stem cells and adult stem cells, which have different functions and characteristics that will be explained in this document. Scientists discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery, in 1998, of how to isolate stem cells from human embryos and grow the cells in the laboratory. These are called human embryonic stem cells. The embryos used in these studies were created for infertility purposes through in vitro fertilization procedures and when they were no longer needed for that purpose, they were donated for research with the informed consent of the donor.
Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, stem cells in developing tissues give rise to the multiple specialized cell types that make up the heart, lung, skin, and other tissues. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease.
It has been hypothesized by scientists that stem cells may, at some point in the future, become the basis for treating diseases such as Parkinson's disease, diabetes, and heart disease.
Scientists want to study stem cells in the laboratory so they can learn about their essential properties and what makes them different from specialized cell types. As scientists learn more about stem cells, it may become possible to use the cells not just in cell-based therapies, but also for screening new drugs and toxins and understanding birth defects. However, as mentioned above, human embryonic stem cells have only been studied since 1998. Therefore, in order to develop such treatments scientists are intensively studying the fundamental properties of stem cells, which include:
determining precisely how stem cells remain unspecialized and self renewing for many years; and
identifying the signals that cause stem cells to become specialized cells.
B. Scope of this document
This primer on stem cells is intended for anyone who wishes to learn more about the biological properties of stem cells, the important questions about stem cells that are the focus of scientific research, and the potential use of stem cells in research and in treating disease. The primer includes information about stem cells derived from the embryo and adult. Much of the information included here is about stem cells derived from human tissues, but some studies of animal-derived stem cells are also described.
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Our mission is to harness the great promise offered by stem cell technology towards the treatment, and possibly cure, of a broad array of intractable human disease for the benefit of patients, family members, physicians and society in general.
StemCells, Inc. is focused on the discovery and development of stem cell therapeutics to treat damage to or degeneration of major organ systems such as the Central Nervous System, Liver and Pancreas.
We are a world leader in the discovery and development of human neural stem cell technology using cells derived from adult (i.e. non-embryonic) brain tissue.
We use a proprietary process to isolate, purify and expand rare candidate stem cells found in adult human tissue.
To date, we have discovered the human neural stem cell as well as a population of rare candidate stem cells found in human liver and pancreas.
We have over forty issued U.S. patents, plus foreign equivalents to some fourteen of our U.S. patents and applications, for a total of over one hundred and seventy individual patents world wide.
Our scientific founders, who are also members of our Scientific Advisory Board, are recognized as world leaders in stem cell biology.
View the 9-24-2007 UBS Presentation by the President & CEO of StemCells, Inc.
Requires Windows Media Player.
StemCells, Inc. is focused on the discovery and development of stem cell therapeutics to treat damage to or degeneration of major organ systems such as the Central Nervous System, Liver and Pancreas.
We are a world leader in the discovery and development of human neural stem cell technology using cells derived from adult (i.e. non-embryonic) brain tissue.
We use a proprietary process to isolate, purify and expand rare candidate stem cells found in adult human tissue.
To date, we have discovered the human neural stem cell as well as a population of rare candidate stem cells found in human liver and pancreas.
We have over forty issued U.S. patents, plus foreign equivalents to some fourteen of our U.S. patents and applications, for a total of over one hundred and seventy individual patents world wide.
Our scientific founders, who are also members of our Scientific Advisory Board, are recognized as world leaders in stem cell biology.
View the 9-24-2007 UBS Presentation by the President & CEO of StemCells, Inc.
Requires Windows Media Player.
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