Category Archives: Stem Cell Videos

Every day we get a call from someone seeking help. Some are battling a life-threatening or life-changing disease. Others call on behalf of a friend or loved one. All are looking for the same thing; a treatment, better still a cure, to ease their suffering.

Almost every day we have to tell them the same thing; that the science is advancing but its not there yet. You can almost feel the disappointment, the sense of despair, on the other end of the line.

If its hard for us to share that news, imagine how much harder it is for them to hear it. Usually by the time they call us they have exhausted all the conventional therapies. In some cases they are not just running out of options, they are also running out of time.

Chasing hope

Sometimes people mention that they went to the website of a clinic that was offering treatments for their condition, claiming they had successfully treated people with that disease or disorder. This week I had three people mention the same clinic, here in the US, that was offering them treatments for multiple sclerosis, traumatic brain injury and chronic obstructive pulmonary disease (COPD). Three very different problems, but the same approach was used for each one.

Its easy to see why people would be persuaded that clinics like this could help them. Their websites are slick and well produced. They promise to take excellent care of patients, often helping take care of travel plans and accommodation.

Theres just one problem. They never offer any scientific evidence on their website that the treatments they offer work. They have testimonials, quotes from happy, satisfied patients, but no clinical studies, no results from FDA-approved clinical trials. In fact, if you explore their sites youll usually find an FAQ section that says something to the effect of they are not offering stem cell therapy as a cure for any condition, disease, or injury. No statements or implied treatments on this website have been evaluated or approved by the FDA. This website contains no medical advice.

What a damning but revealing phrase that is.

Now, it may be that the therapies they are offering wont physically endanger patients though without a clinical trial its impossible to know that but they can harm in other ways. Financially it can make a huge dent in someones wallet with many treatments costing $10,000 or more. And there is also the emotional impact of giving someone false hope, knowing that there was little, if any, chance the treatment would work.

Shining a light in shady areas

U.C. Davis stem cell researcher, CIRM grantee, and avid blogger Paul Knoepfler, highlighted this in a recent post for his blog The Niche when he wrote:

Paul Knoepfler

Patients are increasingly being used as guinea pigs in the stem cell for-profit clinic world via what I call stem cell shot-in-the-dark procedures. The clinics have no logical basis for claiming that these treatments work and are safe.

As the number of stem cell clinics continues to grow in the US and morephysicians add on unproven stem cell injections into their practices as a la carte options, far more patients are being subjected to risky, even reckless physician conduct.

As if to prove how real the problem is, within hours of posting that blog Paul posted another one, this time highlighting how the FDA had sent a Warning Letter to the Irvine Stem Cell Treatment Center saying it had serious concerns about the way it operates and the treatments it offers.

Paul has written about these practices many times in the past, sometimes incurring the wrath of the clinic owners (and very pointed letters from their lawyers). Its to his credit that he refuses to be intimidated and keeps highlighting the potential risks that unapproved therapies pose to patients.

Making progress

As stem cell science advances we are now able to tell some patients that yes, there are promising therapies, based on good scientific research, that are being tested in clinical trials.

There are not as many as we would like and none have yet been approved by the FDA for wider use. But those will come in time.

For now we have to continue to work hard to raise awareness about the need for solid scientific evidence before more people risk undergoing an unproven stem cell therapy.

And we have to continue taking calls from people desperate for help, and tell them they have to be patient, just a little longer.

***

If you are considering a stem cell treatment, the International Society for Stem Cell Research had a terrific online resource, A Closer Look at Stem Cells. In particular, check out the Nine Things to Know about Stem Cell Treatments page.

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stem cell tourism | The Stem Cellar

Cells in animals and in plants that are capable of becoming any other type of cell in that organism and then reproducing more of those cells. Despite the fact that stem cell research is in its infancy, many cosmetics companies claim they are successfully using plant-based or human-derived stem cells in their anti-aging products. The claims run the gamut, from reducing wrinkles to repairing elastin to regenerating cells, so the temptation for consumers to try these products is intense.

The truth is that stem cells in skincare products do not work as claimed; they simply cannot deliver the promised results. In fact, they likely have no effect at all because stem cells must be alive to function as stem cells, and by the time these delicate cells are added to skincare products, they are long since dead and, therefore, useless. Actually, its a good thing that stem cells in skincare products cant work as claimed, given that studies have revealed that they pose a potential risk of cancer.

Plant stem cells, such as those derived from apples, melons, and rice, cannot stimulate stem cells in human skin; however, because they are derived from plants they likely have antioxidant properties. Thats good, but its not worth the extra cost that often accompanies products that contain plant stem cells. Its also a plus that plant stem cells cant work as stem cells in skincare products; after all, you dont want your skin to absorb cells that can grow into apples or watermelons!

There are also claims that because a plants stem cells allow a plant to repair itself or to survive in harsh climates, these benefits can be passed on to human skin. How a plant functions in nature is completely unrelated to how human skin functions, and these claims are completely without substantiation. It doesnt matter how well the plant survives in the desert, no matter how you slather such products on your skin, you still wont survive long without ample water, shade, clothing, and other skin-protective elements.

Another twist on the stem cell issue is that cosmetics companies are claiming they have taken components (such as peptides) out of the plant stem cells and made them stable so they will work as stem cells would or that they will influence the adult stem cells naturally present in skin. In terms of these modified ingredients working like stem cells, this theory doesnt make any sense because stem cells must be complete and intact to function normally. Using peptides or other ingredients to influence adult stem cells in skin is something thats being explored, but to date scientists are still trying to determine how that would work and how it could be done safely. For now, companies claiming theyve isolated substances or extracts from stem cells and made them stable are most likely not telling the whole story. Currently, theres no published, peer-reviewed research showing these stem cell extracts can affect stem cells in human skin.

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Stems cells have the ability to ___ and ___ themselves.

divide and renew

remain undifferentiated

specialized

totipotent

pluripotent

multipotent

totipotent

pluripotent

multipotent

isolate, rejection

ethical

pluripotent, grow

leukemia and lymphoma

disease, replace

drug

inner cell mass

all

multiple, stem

not yet determined

ectoderm, mesoderm, endoderm

growth, maintenance, and repair

Both; some wait for signal, others constantly replace cells that are lost through wear and tear

few

blood-related diseases

multiple diseases (since they can become any cell type)

multiple diseases (since they can become any cell type) and won't be rejected since they're from your own cells

a human being is cloned (nucleus from somatic cell replaces nucleus in egg) but then the embryo is destroyed; requires human egg donor

Example:

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Stem Cells flashcards | Quizlet

Stem cells: Cells that are able to (1) self-renew (can create more stem cells indefinitely) and (2) differentiate into (become) specialized, mature cell types.

Embryonic stem cells: Stem cells that are harvested from a blastocyst. These cells are pluripotent, meaning they can differentiate into cells from all three germ layers.

Embryonic stem cells are isolated from cells in a blastocyst, a very early stage embryo. Once isolated from the blastocyst, these cells form colonies in culture (closely packed groups of cells) and can become cells of the three germ layers, which later make up the adult body.

Adult stem cells (or Somatic Stem Cell): Stem cells that are harvested from tissues in an adult body. These cells are usually multipotent, meaning they can differentiate into cells from some, but not all, of the three germ layers. They are thought to act to repair and regenerate the tissue in which they are found in, but usually they can differentiate into cells of completely different tissue types.

Adult stem cells can be found in a wide variety of tissues throughout the body; shown here are only a few examples.

The Three Germ Layers: These are three different tissue types that exist during development in the embryo and that, together, will later make up the body. These layers include the mesoderm, endoderm, and ectoderm.

The three germ layers form during the gastrula stage of development. The layers are determined by their physical position in the gastrula. This stage follows the zygote and blastocyst stages; the gastrula forms when the embryo is approximately 14-16 days old in humans.

Endoderm: One of the three germ layers. Specifically, this is the inner layer of cells in the embryo and it will develop into lungs, digestive organs, the liver, the pancreas, and other organs.

Mesoderm: One of the three germ layers. Specifically, this is the middle layer of cells in the embryo and it will develop into muscle, bone, blood, kidneys, connective tissue, and related structures.

Ectoderm: One of the three germ layers. Specifically, this is the outer layer of cells in the embryo and it will develop into skin, the nervous system, sensory organs, tooth enamel, eye lens, and other structures.

Differentiation, Differentiated: The process by which a stem cell turns into a different, mature cell. When a stem cell has become the mature cell type, it is called differentiated and has lost the ability to turn into multiple different cell types; it is also no longer undifferentiated.

Directed differentiation: To tightly control a stem cell to become a specific mature cell type. This can be done by regulating the conditions the cell is exposed to (i.e. specific media supplemented with different factors can be used).

The differentiation of stem cells can be controlled by exposing the cells to specific conditions. This regulation can cause the cells to become a specific, desired mature cell type, such as neurons in this example.

Undifferentiated: A stem cell that has not become a specific mature cell type. The stem cell holds the potential to differentiate, to become different cell types.

Potential, potency: The number of different kinds of mature cells a given stem cell can become, or differentiate into.

Totipotent: The ability to turn into all the mature cell types of the body as well as embryonic components that are required for development but do not become tissues of the adult body (i.e. the placenta).

A totipotent cell has the ability to become all the cells in the adult body; such cells could theoretically create a complete embryo, such as is shown here in the early stages.

Pluripotent: The ability to turn into all the mature cell types of the body. This is shown by differentiating these stem cells into cell types of the three different germ layers.

Embryonic stem cells are pluripotent cells isolated from an early stage embryo, called the blastocyst. These isolated cells can turn into cells representative of the three germ layers, all the mature cell types of the body.

Multipotent: The ability to turn into more than one mature cell type of the body, usually a restricted and related group of different cell types.

Mesenchymal stem cells are an example of multipotent stem cells; these stem cells can become a wide variety, but related group, of mature cell types (bone, cartilage, connective tissue, adipose tissue, and others).

Unipotent: The ability to give rise to a single mature cell type of the body.

Tissue Type: A group of cells that are similar in morphology and function, and function together as a unit.

Mesenchyme Tissue: Connective tissue from all three germ layers in the embryo. This tissue can become cells that make up connective tissue, cartilage, adipose tissue, the lymphatic system, and bone in the adult body.

Mesenchyme tissue can come from all three of the germ layers (ectoderm, mesoderm, and endoderm) in the developing embryo, shown here at the gastrula stage. The mesenchyme can become bone, cartilage, connective tissue, adipose tissue, and other components of the adult body.

Hematopoietic Stem Cells: Stem cells that can create all the blood cells (red blood cells, white blood cells, and platelets). These stem cells reside within bone marrow in adults and different organs in the fetus.

Hematopoietic stem cells can become, or differentiate into, all the different blood cell types. This process is referred to as hematopoiesis.

Bone marrow: Tissue within the hollow inside of bones that contains hematopoietic stem cells and mesenchymal stem cells.

Development: The process by which a fertilized egg (from the union of a sperm and egg) becomes an adult organism.

Zygote: The single cell that results from a sperm and egg uniting during fertilization. The zygote undergoes several rounds of cell division before it becomes an embryo (after about four days in humans).

When an egg is fertilized by a sperm, the resultant single cell is referred to as a zygote.

Blastocyst: A very early embryo (containing approximately 150 cells) that has not yet implanted into the uterus. The blastocyst is a fluid-filled sphere that contains a group of cells inside it (called the inner cell mass) and is surrounded by an outer layer of cells (the trophoblast, which forms the placenta).

The blastocyst contains three primary components: the inner cell mass, which can become the adult organism, the trophoblast, which becomes the placenta, and the blastocoele, which is a fluid-filled space. The blastocyst develops into the gastrula, a later stage embryo.

Inner Cell Mass: A small group of cells that are attached inside the blastocyst. Human embryonic stem cells are created from these cells in blastocysts that are four or five days post-fertilization. The cells from the inner cell mass have the potential to develop into an embryo, then later the fetus, and eventually the entire body of the adult organism.

Cells taken from the inner cell mass of the blastocyst (a very early stage embryo) can become embryonic stem cells.

Embryo: The developing organism from the end of the zygote stage (after about four days in humans) until it becomes a fetus (until 7 to 8 weeks after conception in humans).

Models: A biological system that is easy to study and similar enough to another, more complex system of interest so that knowledge of the model system can be used to better understand the more complex system. Such systems can include cells and whole organisms.

Model organism: An organism that is easy to study and manipulate and is similar enough to another organism of interest so that by understanding the model organism, a greater understanding of the other organism may be gained. For example, rats and mice can be used as model organisms to better understand humans.

Shown are several different model organisms frequently used in laboratory studies.

Severe Combined Immune-Deficient (SCID) mouse: A mouse lacking a functional immune system, specifically lacking or abnormal T and B lymphocytes. This is due to inbreeding or genetic engineering. They are extensively used for tissue transplants, because they lack an immune system to reject foreign substances, and for studying an immunocompromised system.

Cellular models: A cell system that can be used to understand normal, or diseased, functions that the cell has within the body. By taking cells from the body and studying them outside of the body, in culture, different conditions can be manipulated and the results studied, whereas this can be much more difficult, or impossible, to do within the body.

Stem cells obtained from different tissues of the body can be used as models to study normal, or diseased, cells in these tissues.

Cell Types:

Somatic Cell: Any cell in the body, developing or adult, other than the germline cells (the gametes, or sperm and eggs).

Gametes: The cells in the body that carry the genetic information that will be passed to the offspring. In other words, these are the germline cells: an egg (for females) or sperm (for males) cell.

Other terms:

Regenerative Medicine: A field of research that investigates how to repair or replace damaged tissues, usually by using stem cells. In this manner, stem cells may be differentiated into, or made to become, the type of cell that is damaged and then used in transplants. Also see clinical trials.

Clinical trials: A controlled test of a new drug or treatment on human subjects, normally performed after successful trials with model organisms. ClinicalTrials.gov lists many stem cell clinical trials.

Stem cells have great potential to treat a wide variety of human diseases and medical conditions.

Cell Surface Marker proteins, or simply Cell Markers: A protein on the surface of a cell that identifies the cell as a certain cell type.

Somatic Cell Nuclear Transfer (SCNT): A technique that uses an egg and a somatic cell (a non-germline cell). The nucleus, which contains the genetic material, is removed from the egg and the nucleus from the somatic cell is removed and combined with the egg. The resultant cell contains the genetic material of the nucleus donor, and is turned into a totipotent state by the egg. This cell has the potential to develop into an organism, a clone of the nucleus donor.

Dolly the sheep was cloned through somatic cell nuclear transfer (SCNT). An adult cell from the mammary gland of a Finn-Dorset ewe acted as the nuclear donor; it was fused with an enucleated egg from a Scottish Blackface ewe, which acted as the cytoplasmic (or egg) donor. An electrical pulse acted to fuse the cells and activate the oocyte after injection into the surrogate mother ewe. A successfully implanted oocyte developed into the lamb Dolly, a clone of the nuclear donor, the Finn-Dorset ewe.

Clone: A genetic, identical copy of an individual organism through asexual methods. A clone can be created through somatic cell nuclear transfer.

Other stem cell glossaries:

Image credits Images of Endoderm, Mesoderm, Ectoderm, Bone Marrow, Neurons, Cartilage, Hand Skeleton, Connective and Adipose Tissue, Gastrula, Clinical Trials, Mouse, Rat, Drosophila, C. Elegans, Arabidopsis, Sea Urchin, Xenopus, Somatic Cell Nuclear Transfer to Create Dolly and other images were taken from the Wikimedia Commons and redistributed and altered freely as they are all in the public domain. The image of Hematopoiesis was also taken from the Wikimedia Commons and redistributed according to the GNU Free Documentation License.

2009. Teisha Rowland. All rights reserved.

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HOME UNDERSTANDING PARKINSON'S Living with Parkinson's

Stem cells are a renewable source of tissue that can be coaxed to become different cell types of the body. The best-known examples are the embryonic stem (ES) cells found within an early-stage embryo. These cells can generate all the major cell types of the body (they are pluripotent). Stem cells have also been isolated from various other tissues, including bone marrow, muscle, heart, gut and even the brain. These adult stem cells help with maintenance and repair by becoming specialized cells types of the tissue or organ where they originate. For example, special stem cells in the bone marrow give rise to all the various types of blood cells (similar blood cell-forming stem cells have also been isolated from umbilical cord blood).

Because adult stem cells become more committed to a particular tissue type during development, unlike embryonic stem cells, they appear to only develop into a limited number of cell types (they are multipotent).

In addition to ES cells, induced pluripotent stem (iPS) cells, discovered in 2007, represent an important development in stem cell research to treat diseases like Parkinsons disease. Essentially, iPS cells are man-made stem cells that share ES cells' ability to become other cell types. IPS cells are created when scientists convert or "reprogram" a mature cell, such as a skin cell, into an embryonic-like state. These cells may have potential both for cell replacement treatment approaches in patients and as disease models that scientists could use in screening new drugs.

IPS cell technology is somewhat related to a previous method called somatic cell nuclear transfer (SCNT) or therapeutic cloning (the technology that gave us Dolly the Sheep). Unlike the iPS cell approach, which converts adult cells directly into stem cells, SCNT involves transferring the genetic material of an adult cell into an unfertilized human egg cell, allowing the egg cell to form an early-stage embryo and then collecting its ES cells (which are now genetic clones of the person who donated the adult cell). To date, however, this has not been successfully demonstrated with human cells and iPS cell methods may be replacing SCNT as a more viable option.

A potentially exciting use for iPS cells is the development of cell models of Parkinsons disease. In theory, scientists could use cells from people living with Parkinsons disease to create iPS cell models of the disease that have the same intrinsic cellular machinery of a Parkinsons patient. Researchers could use these cell models to evaluate genetic and environmental factors implicated in Parkinsons disease.

Stem cell research has the potential to significantly impact the development of disease-modifying treatments for Parkinson's disease, and considerable progress has been made in creating dopamine-producing cells from stem cells. The development of new cell models of Parkinsons disease is a particularly promising area of stem cell research, as the current lack of progressive, predictive models of Parkinsons disease remains a major barrier to drug development. Cell models of Parkinsons disease generated from stem cells could help researchers screen drugs more efficiently than in currently available animal models, and study the underlying biological mechanisms associated with Parkinsons disease in cells taken from people living with the disease.

However, there are many challenges that need to be overcome before stem cell-based cell replacement therapies for Parkinsons disease are a reality. Work is still needed to generate robust cells, in both quality and quantity, that can also survive and function appropriately in a host brain. Although ES (and now iPS) cells hold great potential, we do not yet know which stem cell type ultimately holds the greatest promise. Thus, researchers require scientific freedom to pursue research on all types including ES, adult and IPS cells in order to yield results for patients.

The Michael J. Fox Foundation played an early role in supporting work in stem cell research for Parkinsons disease, including funding the original proof of principle demonstrating that ES cells could provide a robust source of dopamine neurons. Since that time, significant other funding resources at both the state and federal levels have been unleashed to support the whole field, allowing the Foundation to continue to target strategic funding in other critical areas of developing therapies for Parkinsons disease. The Foundation will continue to monitor Parkinsons disease specific stem cell developments for opportunities where the Foundation can help in advancing this research.

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Contemporary Examples

Now, Rich writes, when Barack Obama ended the Bush stem-cell policy last week, there were no such overheated theatrics.

It launches curricular reviews and stem-cell initiatives; it raises money, and buys up property (or at least, it used to).

Many women who undergo IVF either discard their leftover embryos or donate them for stem-cell research.

Maybe they would, but this has played absolutely no part in the stem-cell debate.

I am often criticized for previously voting for John Kerry and my support of stem-cell research.

The stem-cell controversy is really about abortion, of course.

Whatever, the result is that the promise of stem-cell research is delayed or unrealized.

British Dictionary definitions for stem-cell Expand

(histology) an undifferentiated cell that gives rise to specialized cells, such as blood cells

stem-cell in Medicine Expand

stem cell n. An unspecialized cell that gives rise to a specific specialized cell, such as a blood cell.

stem-cell in Science Expand

stem-cell in Culture Expand

A cell from which a variety of other cells can develop through the process of cellular differentiation. Stem cells can produce only a certain group of cells (as with skin stem cells) or any cell in the body (as with embryonic stem cells).

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Stem-cell | Define Stem-cell at Dictionary.com

Cellular immortality happens upon impairment of cell-cycle checkpoint pathways (p53/p16/pRb), reactivation or up-regulation of telomerase enzyme, or upregulation of some oncogenes or oncoproteins leading to a higher rate of cell division.... more

Cellular immortality happens upon impairment of cell-cycle checkpoint pathways (p53/p16/pRb), reactivation or up-regulation of telomerase enzyme, or upregulation of some oncogenes or oncoproteins leading to a higher rate of cell division. There are also some other factors and mechanisms involved in immortalization, which need to be discovered. Immortalization of cells derived from different sources and establishment of immortal cell lines has proven useful in understanding the molecular pathways governing cell developmental cascades in eukaryotic, especially human cells. After the breakthrough of achieving the immortal cells and understanding their critical importance in the field of molecular biology, intense efforts have been dedicated to establish cell lines useful for elucidating the functions of telomerase, developmental lineage of progenitors, self renewal potency, cellular transformation, differentiation patterns and some bioprocesses, like odontogenesis. Meanwhile, discovering the exact mechanisms of immortality, a major challenge for science yet, is believed to open new gateways toward understanding and treatment of cancer in long shot. This review summarizes the methods involved in establishing immortality, its advantages, and the challenges still being faced in this field.

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Academia.edu | Documents in Stem Cells - Academia.edu

What are Stem Cells?

Types of Stem Cells

Why are Stem Cells Important?

Can doctors use stem cells to treat patients?

Pros and Cons of Using Stem Cells

What are Stem Cells?

There are several different types of stem cells produced and maintained in our system throughout life. Depending on the circumstances and life cycle stages, these cells have different properties and functions. There are even stem cells that have been created in the laboratory that can help us learn more about how stem cells differentiate and function. A few key things to remember about stem cells before we venture into more detail:

Stem cells are the foundation cells for every organ and tissue in our bodies. The highly specialized cells that make up these tissues originally came from an initial pool of stem cells formed shortly after fertilization. Throughout our lives, we continue to rely on stem cells to replace injured tissues and cells that are lost every day, such as those in our skin, hair, blood and the lining of our gut.

Source ISSCR

Stem Cell History

Until recently, scientists primarily worked with two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic "somatic" or "adult" stem cells. Scientists discovered ways to derive embryonic stem cells from early mouse embryos nearly 30 years ago, in 1981. The detailed study of the biology of mouse stem cells led to the discovery, in 1998, of a method to derive stem cells from human embryos and grow the cells in the laboratory. These cells are called human embryonic stem cells. The embryos used in these studies were created for reproductive purposes through in vitro fertilization procedures. When they were no longer needed for that purpose, they were donated for research with the informed consent of the donor. In 2006, researchers made another breakthrough by identifying conditions that would allow some specialized adult cells to be "reprogrammed" genetically to assume a stem cell-like state. This new type of stem cell is now known as induced pluripotent stem cells (iPSCs).

Source NIH

Types of Stem Cells

Adult Stem Cells (ASCs):

ASCs are undifferentiated cells found living within specific differentiated tissues in our bodies that can renew themselves or generate new cells that can replenish dead or damaged tissue. You may also see the term somatic stem cell used to refer to adult stem cells. The term somatic refers to non-reproductive cells in the body (eggs or sperm). ASCs are typically scarce in native tissues which have rendered them difficult to study and extract for research purposes.

Resident in most tissues of the human body, discrete populations of ASCs generate cells to replace those that are lost through normal repair, disease, or injury. ASCs are found throughout ones lifetime in tissues such as the umbilical cord, placenta, bone marrow, muscle, brain, fat tissue, skin, gut, etc. The first ASCs were extracted and used for blood production in 1948. This procedure was expanded in 1968 when the first adult bone marrow cells were used in clinical therapies for blood disease.

Studies proving the specificity of developing ASCs are controversial; some showing that ASCs can only generate the cell types of their resident tissue whereas others have shown that ASCs may be able to generate other tissue types than those they reside in. More studies are necessary to confirm the dispute.

Types of Adult Stem Cells

Embryonic Stem Cells (ESCs):

During days 3-5 following fertilization and prior to implantation, the embryo (at this stage, called a blastocyst), contains an inner cell mass that is capable of generating all the specialized tissues that make up the human body. ESCs are derived from the inner cell mass of an embryo that has been fertilized in vitro and donated for research purposes following informed consent. ESCs are not derived from eggs fertilized in a womans body.

These pluripotent stem cells have the potential to become almost any cell type and are only found during the first stages of development. Scientists hope to understand how these cells differentiate during development. As we begin to understand these developmental processes we may be able to apply them to stem cells grown in vitro and potentially regrow cells such as nerve, skin, intestine, liver, etc for transplantation.

Induced Pluripotent Stem Cells (iPSCs)

Induced pluripotent stem cells are stem cells that are created in the laboratory, a happy medium between adult stem cells and embryonic stem cells. iPSCs are created through the introduction of embryonic genes into a somatic cell (a skin cell for example) that cause it to revert back to a stem cell like state. These cells, like ESCs are considered pluripotent Discovered in 2007, this method of genetic reprogramming to create embryonic like cells, is novel and needs many more years of research before use in clinical therapies.

NIH

Why are Stem Cells Important?

Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, the inner cells give rise to the entire body of the organism, including all of the many specialized cell types and organs such as the heart, lung, skin, sperm, eggs 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.

Given their unique regenerative abilities, stem cells offer new potentials for treating diseases such as diabetes, and heart disease. However, much work remains to be done in the laboratory and the clinic to understand how to use these cells for cell-based therapies to treat disease, which is also referred to as regenerative or reparative medicine.

Laboratory studies of stem cells enable scientists to learn about the cells essential properties and what makes them different from specialized cell types. Scientists are already using stem cells in the laboratory to screen new drugs and to develop model systems to study normal growth and identify the causes of birth defects.

Research on stem cells continues to advance knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. Stem cell research is one of the most fascinating areas of contemporary biology, but, as with many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates new discoveries.

Source NIH

Can doctors use stem cells to treat patients?

Some stem cells, such as the adult bone marrow or peripheral blood stem cells, have been used in clinical therapies for over 40 years. Other therapies utilizing stem cells include skin replacement from adult stem cells harvested from hair follicles that have been grown in culture to produce skin grafts. Other clinical trials for neuronal damage/disease have also been conducted using neural stem cells. There were side effects accompanying these studies and further investigation is warranted. Although there is much research to be conducted in the future, these studies give us hope for the future of therapeutics with stem cell research.

Potential Therapies using Stem Cells

Adult Stem Cell Therapies

Bone marrow and peripheral blood stem cell transplants have been utilized for over 40 years as therapy for blood disorders such as leukemia and lymphoma, amongst many others. Scientists have also shown that stem cells reside in most tissues of the body and research continues to learn how to identify, extract, and proliferate these cells for further use in therapy. Scientists hope to yield therapies for diseases such as type I diabetes and repair of heart muscle following heart attack.

Scientists have also shown that there is potential in reprogramming ASCs to cause them to transdifferentiate (turn back into a different cell type than the resident tissue it was replenishing).

Embryonic Stem Cell (ESC) Therapies

There is potential with ESCs to treat certain diseases in the future. Scientists continue to learn how ESCs differentiate and once this method is better understood, the hope is to apply the knowledge to get ESCs to differentiate into the cell of choice that is needed for patient therapy. Diseases that are being targeted with ESC therapy include diabetes, spinal cord injury, muscular dystrophy, heart disease, and vision/hearing loss.

Induced Pluripotent Stem Cell Therapies

Therapies using iPSCs are exciting because somatic cells of the recipient can be reprogrammed to en ESC like state. Then mechanisms to differentiate these cells may be applied to generate the cells in need. This is appealing to clinicians because this avoids the issue of histocompatibility and lifelong immunosuppression, which is needed if transplants use donor stem cells.

iPS cells mimic most ESC properties in that they are pluripotent cells, but do not currently carry the ethical baggage of ESC research and use because iPS cells have not been able to be manipulated to grow the outer layer of an embryonic cell required for the development of the cell into a human being.

Pros and Cons of Using Various Stem Cells

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What are Stem Cells? | Stem Cells | University of Nebraska ...

En Espaol

The term stem cell by itself can be misleading. In fact, there are many different types of stem cells, each with very different potential to treat disease.

Stem Cell Pluripotent Embryonic Stem Cell Adult Stem Cell iPS Cell Cancer Stem Cell

By definition, all stem cells:

Pluripotent means many "potentials". In other words, these cells have the potential of taking on many fates in the body, including all of the more than 200 different cell types. Embryonic stem cells are pluripotent, as are induced pluripotent stem (iPS) cells that are reprogrammed from adult tissues. When scientists talk about pluripotent stem cells, they mostly mean either embryonic or iPS cells.

Embryonic stem cells come from pluripotent cells, which exist only at the earliest stages of embryonic development. In humans, these cells no longer exist after about five days of development.

When isolated from the embryo and grown in a lab dish, pluripotent cells can continue dividing indefinitely. These cells are known as embryonic stem cells.

James Thomson, a professor in the Department of Cell and Regenerative Biology at the University of Wisconsin, derived the first human embryonic stem cell lines in 1998. He now shares a joint appointment at the University of California, Santa Barbara, a CIRM-funded institution.

Adult stem cells are found in the various tissues and organs of the human body. They are thought to exist in most tissues and organs where they are the source of new cells throughout the life of the organism, replacing cells lost to natural turnover or to damage or disease.

Adult stem cells are committed to becoming a cell from their tissue of origin, and cant form other cell types. They are therefore also called tissue-specific stem cells. They have the broad ability to become many of the cell types present in the organ they reside in. For example:

Unlike embryonic stem cells, researchers have not been able to grow adult stem cells indefinitely in the lab, but this is an area of active research.

Scientists have also found stem cells in the placenta and in the umbilical cord of newborn infants, and they can isolate stem cells from different fetal tissues. Although these cells come from an umbilical cord or a fetus, they more closely resemble adult stem cells than embryonic stem cells because they are tissue-specific. The cord blood cells that some people bank after the birth of a child are a form of adult blood-forming stem cells.

CIRM-grantee IrvWeissman of the Stanford University School of Medicine isolated the first blood-forming adult stem cell from bone marrow in 1988 in mice and later in humans.

Irv Weissman explains the difference between an adult stem cell and an embryonic stem cell (video)

An induced pluripotent stem cell, or iPS cell, is a cell taken from any tissue (usually skin or blood) from a child or adult and is genetically modified to behave like an embryonic stem cell. As the name implies, these cells are pluripotent, which means that they have the ability to form all adult cell types.

Shinya Yamanaka, an investigator with joint appointments at Kyoto University in Japan and the Gladstone Institutes in San Francisco, created the first iPS cells from mouse skin cells in 2006. In 2007, several groups of researchers including Yamanaka and James Thomson from the University of Wisconsin and University of California, Santa Barbara generated iPS cells from human skin cells.

Cancer stem cells are a subpopulation of cancer cells that, like stem cells, can self-renew. However, these cellsrather than growing into tissues and organspropagate the cancer, maturing into the many types of cells that are found in a tumor.

Cancer stem cells are a relatively new concept, but they have generated a lot of interest among cancer researchers because they could lead to more effective cancer therapies that can treat tumors resistant to common cancer treatments.

However, there is still debate on which types of cancer are propelled by cancer stem cells. For those that do, cancer stem cells are thought to be the source of all cells that make up the cancer.

Conventional cancer treatments, such as chemotherapy, may only destroy cells that form the bulk of the tumor, leaving the cancer stem cells intact. Once treatment is complete, cancer stem cells that still reside within the patient can give rise to a recurring tumor. Based on this hypothesis, researchers are trying to find therapies that destroy the cancer stem cells in the hopes that it truly eradicates a patients cancer.

John Dick from the University of Toronto first identified cancer stem cells in 1997. Michael Clarke, then at the University of Michigan, later found the first cancer stem cell in a solid tumor, in this case, breast cancer. Now at Stanford University School of Medicine, Clarke and his group have found cancer stem cells in colon cancer and head and neck cancers.

Find out More:

Catriona Jamieson talks about therapies based on cancer stem cells (4:32)

Stanford Publication: The true seeds of cancer

UCSD Publication: From Bench to Bedside in One Year: Stem Cell Research Leads to Potential New Therapy for Rare Blood Disorder

Updated 2/16

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Stem Cell Key Terms | California's Stem Cell Agency

Stem cells are cells in the body that have the potential to turn into anything, such as a skin cell, a liver cell, a brain cell, or a blood cell. Stem cells that turn into blood cells are called hematopoietic (heh-mat-uh-poy-EH-tik)stem cells. These cells are capable of developing into the three types of blood cells:

Hematopoietic stem cells can be found in bone marrow (the spongy tissue inside bones), the bloodstream, and the umbilical cord blood of newborn babies.

A stem cell transplant (sometimes called a bone marrow transplant) can replenish a child's supply of healthy hematopoietic stem cells after they have been depleted. It's used to treat a wide range of diseases, including cancers like leukemia, lymphoma, neuroblastoma, Wilms tumor, and certain testicular or ovarian cancers; blood disorders; immune system diseases; and bone marrow syndromes.

Transplanted hematopoietic stem cells are put into the bloodstream through an intravenous (IV) line, much like a blood transfusion. Once in the body, they can produce healthy new blood and immune system cells.

The two main types of stem cell transplants are autologous (aw-TAHL-uh-gus)and allogeneic (al-uh-juh-NEE-ik). The type of transplant needed will depend on the child's specific medical condition and the availability of a matching donor.

This procedure may be done once or many times, depending on the need. Sometimes doctors will use extra-high doses of chemotherapy during treatment (to kill as many cancer cells as possible) if they know a patient will be getting a stem cell transplant soon after.

Unlike with an autologous transplant, there is a risk of a child's body rejecting the donated cells. This means that the body's ownimmune cells destroy the transplanted stem cells because they sense they are foreign.Sometimes, despite the donor being a good match, the transplant simply may not take. Other times, the donor cells can begin to make immune cells that attack the recipient's body. This condition is called graft-versus-host disease, and can be quite serious. Fortunately, most cases are successfully treated with steroids and other medicines.

Sometimes, an upside of graft-versus-host disease is that the newly transplanted cells recognize the body's cancer cells as different or foreign, and actually work to fight them.

Stem cell transplantation is a very complex process that may span several months. A team of doctors is usually involved in determining if a child is a candidate and, if so, whether the transplant will be autologous or allogeneic.

For an allogeneic transplant, a compatible donor will be sought among family members or through a national registry of volunteers. Once a match is found, the donor's stem cells will be harvested. Three different types of hematopoietic stem cells can be collected or harvested:

While all three types can replenish a patient's blood and bone marrow cells, there are advantages and disadvantages to each. The doctor will suggest the best type of stem cell for your child's illness.

The next step in the transplantation process is conditioning therapy, which kills unhealthy cells (like cancer cells) to make room for stem cells to grow and/or weakens the immune system so that theres less chance of the body rejecting the new cells.

One type of conditioning therapy delivers high doses of chemotherapy and/or radiation to kill cells, destroy the bone marrow, and weaken the immune system. Most kids will get this type of therapy. Another type of conditioning therapy delivers lower doses of chemotherapy, radiation, or another treatment to weaken the immune system. The doctor will decide which type of conditioning therapy is best.

Soon after the conditioning phase, the transplant itself will be done through intravenous (IV)infusion, and healthy stem cells will be introduced to the child's body. After the infusion, the child will be watched very closely to make sure the new stem cells are settling into the marrow and beginning to make new blood cells (called engrafting). Doctors will watch for any signs of rejection as well as graft-verses-host disease in kids with allogeneic transplants.

Engrafting takes an average of 2 weeks, but can be as quick as 1 week or as long as 6 weeks. Your child will receive medicines to promote engrafting and prevent rejection and graft-versus-host disease.

Kids who receive stem cell transplants have a high risk of infection. During conditioning therapy and while the transplant is engrafting, their immune systems are weakened and unable to fight bacteria and other germs that enter the body. Children who receive an allogeneic transplant have an even greater risk of infection because they require medicines to further suppress their immune systems to reduce the chance of rejection.

Because of these risks, a child who's had a stem cell transplant will not be released from the hospital until doctors are sure the transplant has successfully engrafted and the child is otherwise doing well.

Once released, a child needs very close monitoring and follow-up care. School and other public indoor areas may be off limits for 3 months to a year, and other places might be restricted as well. This is because for kids with a compromised immune system, even a simple infection like a common cold can be serious and even life-threatening if untreated.

The stress of having a child who is being treated for cancer or another serious conditioncan be overwhelming for a family. That stress can grow when treatment requires a long "isolation period," as is necessary with a stem cell transplant.

To find out what support is available to you and your child, talk to your doctor, a hospital social worker, or child life specialist. Many resources are available that can help you get through this difficult time.

Date reviewed: August 2015

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Stem Cell Transplants (For Parents) - KidsHealth