what deseases can be treated by stem cells?

Answer 1

Hello again Knower,

Here's another quote from http://stemcells.nih.gov/info/health.asp

"Adult stem cells, such as blood-forming stem cells in bone marrow (called hematopoietic stem cells, or HSCs), are currently the only type of stem cell commonly used to treat human diseases. Doctors have been transferring HSCs in bone marrow transplants for over 40 years. More advanced techniques of collecting, or "harvesting," HSCs are now used in order to treat leukemia, lymphoma and several inherited blood disorders.

The clinical potential of adult stem cells has also been demonstrated in the treatment of other human diseases that include diabetes and advanced kidney cancer. However, these newer uses have involved studies with a very limited number of patients."

[page last updated Friday, October 6, 2006)

However, clinical trials are now going on..
Many clinical trials are reported at http://www.clinicaltrials.gov/

I typed..."stem cell"....in the search box and came up with over
500 recruiting, going on, or finished..
[use quotes to force searching stem cell as a phrase]

Answer 2

1

Answer 3

"Medical researchers believe that stem cell research has the potential to change the face of human disease. A number of current treatments already exist, although the majority of them are not commonly used because they tend to be experimental and not very cost-effective. Medical researchers anticipate being able to use technologies derived from stem cell research to treat cancer, parkinson's disease, spinal cord injuries, and muscle damage, amongst a number of other diseases, impairments and conditions. However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research."
This, and more, available on the free, online encyclopedia, Wikipedia at:
http://en.wikipedia.org/wiki/Stem_cells

Hope this helps!

Answer 4

Down Syndrome, Genetic and other serious diseases of childhood can be treated by stem cell transplantation

Answer 5

Leukemia

Answer 6

Well it could help muscular distrophy, if you have an unballance of cells in your blood, any many more if you need more of one cell.

Answer 7

None.

Answer 8

None yet.

Answer 9

Stem cell

Mouse embryonic stem cells with fluorescent marker.Stem cells are primal cells that retain the ability to renew themselves through cell division and can differentiate into a wide range of specialized cell types. Research in the stem cell field grew out of findings by Canadian scientists Ernest A. McCulloch and James E. Till in the 1960s. The two categories of stem cells are embryonic stem cells, derived from blastocysts and adult stem cells, derived from umbilical cord blood or bone marrow.[1] In a blastocyst of a developing embryo, stem cells differentiate into all of the specialised embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells. As stem cells can be readily grown and transformed into specialized tissues such as muscles or nerves through cell culture, their use in medical therapies has been proposed.

Stem cell properties

Defining properties

The rigorous definition of a stem cell requires that it possesses two properties:

Self-renewal - the ability to go through numerous cycles of cell division while maintaining the undifferentiated state.
Unlimited potency - the capacity to differentiate into any mature cell type. In a strict sense, this makes stem cells either totipotent or pluripotent, although some multipotent and/or unipotent progenitor cells are sometimes referred to as stem cells.
These properties can be illustrated in vitro, using methods such as clonogenic assays, where the progeny of single cell is characterized. However, in vitro culture conditions can alter the behavior of cells, making it unclear whether the cells will behave in a similar manner in vivo. Considerable debate exists whether some proposed adult cell populations are truly stem cells.

Stem cells - Stem Cells are cells that have the ability to self-replicate and give rise to specialized cells. Stem cells can be found at different stages of fetal development and are present in a wide range of adult tissues. Many of the terms used to distinguish stem cells are based on their origins and the cell types of their progeny.

There are three basic types of stem cells. Totipotent stem cells, meaning their potential is total, have the capacity to give rise to every cell type of the body and to form an entire organism. Pluripotent stem cells, such as embryonic stem cells, are capable of generating virtually all cell types of the body but are unable to form a functioning organism. Multipotent stem cells can give rise only to a limited number of cell types. For example, adult stem cells, also called organ- or tissue-specific stem cells, are multipotent stem cells found in specialized organs and tissues after birth. Their primary function is to replenish cells lost from normal turnover or disease in the specific organs and tissues in which they are found.

Totipotent stem cells occur at the earliest stage of embryonic development. The union of sperm and egg creates a single totipotent cell. This cell divides into identical cells in the first hours after fertilization. All these cells have the potential to develop into a fetus when they are placed into the uterus. The first differentiation of totipotent cells forms a hollow sphere of cells called the blastocyst, which has an outer layer of cells and an inner cell mass inside the sphere. The outer layer of cells will form the placenta and other supporting tissues during fetal development, whereas cells of the inner cell mass go on to form all three primary germ layers: ectoderm, mesoderm, and endoderm. The three germ layers are the embryonic source of all types of cells and tissues of the body. Embryonic stem cells are derived from the inner cell mass of the blastocyst. They retain the capacity to give rise to cells of all three germ layers. However, embryonic stem cells cannot form a complete organism because they are unable to generate the entire spectrum of cells and structures required for fetal development. Thus, embryonic stem cells are pluripotent, not totipotent, stem cells.

Embryonic germ (EG) cells differ from embryonic stem cells in the tissue sources from which they are derived, but appear to be similar to embryonic stem cells in their pluripotency. Human embryonic germ cell lines are established from the cultures of the primordial germ cells obtained from the gonadal ridge of late-stage embryos, a specific part that normally develops into the testes or the ovaries. Embryonic germ cells in culture, like cultured embryonic stem cells, form embryoid bodies, which are dense, multilayered cell aggregates consisting of partially differentiated cells. The embryoid body-derived cells have high growth potential. The cell lines generated from cultures of the embryoid body cells can give rise to cells of all three embryonic germ layers, indicating that embryonic germ cells may represent another source of pluripotent stem cells.

Much of the knowledge about embryonic development and stem cells has been accumulated from basic research on mouse embryonic stem cells. Since 1998, however, research teams have succeeded in growing human embryonic stem cells in culture. Human embryonic stem cell lines have been established from the inner cell mass of human blastocysts that were produced through in vitro fertilization procedures. The techniques for growing human embryonic stem cells are similar to those used for growth of mouse embryonic stem cells. However, human embryonic stem cells must be grown on a mouse embryonic fibroblast feeder layer or in media conditioned by mouse embryonic fibroblasts. Human embryonic stem cell lines can be maintained in culture to generate indefinite numbers of identical stem cells for research. As with mouse embryonic stem cells, culture conditions have been designed to direct differentiation into specific cell types (for example, neural and hematopoietic cells).

Adult stem cells occur in mature tissues. Like all stem cells, adult stem cells can self-replicate. Their ability to self-renew can last throughout the lifetime of individual organisms. But unlike embryonic stem cells, it is usually difficult to expand adult stem cells in culture. Adult stem cells reside in specific organs and tissues, but account for a very small number of the cells in tissues. They are responsible for maintaining a stable state of the specialized tissues. To replace lost cells, stem cells typically generate intermediate cells called precursor or progenitor cells, which are no longer capable of self-renewal. However, they continue undergoing cell divisions, coupled with maturation, to yield fully specialized cells. Such stem cells have been identified in many types of adult tissues, including bone marrow, blood, skin, gastrointestinal tract, dental pulp, retina of the eye, skeletal muscle, liver, pancreas, and brain. Adult stem cells are usually designated according to their source and their potential. Adult stem cells are multipotent because their potential is normally limited according to their source and their potential. Adult stem cells are multipotent because their potential is normally limited to one or more lineages of specialized cells. However, a special multipotent stem cell that can be found in bone marrow, called the mesenchymal stem cell, can produce all cell types of bone, cartilage, fat, blood, and connective tissues.

Blood stem cells, or hematopoietic stem cells, are the most studied type of adult stem cells. The concept of hematopoietic stem cells is not new, since it has been long realized that mature blood cells are constantly lost and destroyed. Billions of new blood cells are produced each day to make up the loss. This process of blood cell generation called hematopoiesis, occurs largely in the bone marrow. Another emerging source of blood stem cells is human umbilical cord blood. Similar to bone marrow, umbilical cord blood can be used as a source material of stem cells for transplant therapy. However, because of the limited number of stem cells in umbilical cord blood, most of the procedures are performed for young children of relatively low body weight.

Neural stem cells, the multipotent stem cells that generate nerve cells, are a new focus in stem cell research. Active cellular turnover does not occur in the adult nervous system as it does in renewing tissues such as blood or skin. Because of this observation, it had been a dogma that the adult brain and spinal cord were unable to regenerate new nerve cells. However, since the early 1990s, neural stem cells have been isolated from the adult brain as well as fetal brain tissues. Stem cells in the adult brain are found in the areas called the subventricular zone and the ventricle zone. Another location of brain stem cells occurs in the hippocampus, a special structure of the cerebral cortex related to memory function. Stem cells isolated from these areas are able to divide and to give rise to nerve cells (neurons) and neuron-supporting cell types in culture.

Stem cell plasticity refers to the phenomenon of adult stem cells from one tissue generating the specialized cells of another tissue. The long-standing concept of adult organ-specific stem cells is that they are restricted to producing the cell types of their specific tissues. However, a series of studies have challenged the concept of tissue restriction of adult stem cells. Although the stem cells appear able to cross their tissue-specific boundaries, crossing occurs generally at a low frequency and mostly only under conditions of host organ damage. The finding of stem cell plasticity carries significant implications for potential cell therapy. For example, if differentiation can be redirected, stem cells of abundant source and easy access, such as blood stem cells in bone marrow or umbilical cord blood, could be used to substitute stem cells in tissues that are difficult to isolate, such as heart and nervous system tissue.

Potency definitions

Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.Potency specifies the differentiation potential (the potential to differentiate into different cell types) of the stem cell.

Totipotent stem cells are produced from the fusion of an egg and sperm cell. Cells produced by the first few divisions of the fertilized egg are also totipotent. These cells can differentiate into embryonic and extraembryonic cell types.
Pluripotent stem cells are the descendants of totipotent cells and can differentiate into cells derived from the three germ layers.
Multipotent stem cells can produce only cells of a closely related family of cells (e.g. hematopoietic stem cells differentiate into red blood cells, white blood cells, platelets, etc.).
Unipotent cells can produce only one cell type, but have the property of self-renewal which distinguishes them from non-stem cells.

Embryonic stem cells

Embryonic stem cells (ES cells) are stem cells derived from the inner cell mass of a blastocyst. A blastocyst is an early stage embryo - approximately 4 to 5 days old in humans and consisting of 50-150 cells. ES cells are pluripotent, and give rise during development of all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.

When given no stimuli for differentiation, ES cells will continue to divide in vitro and each daughter cell will remain pluripotent. The pluripotency of ES cells has been rigorously demonstrated in vitro and in vivo, thus they can be indeed classified as stem cells.

Because of their unique combined abilities of unlimited expansion and pluripotency, embryonic stem cells are a potential source for regenerative medicine and tissue replacement after injury or disease. To date, no approved medical treatments have been derived from embryonic stem cell research. This is not surprising considering that many nations currently have a moratorium on either ES cell research or the production of new ES cell lines.

Adult stem cells

Stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiationAdult stem cells are undifferentiated cells found throughout the body that divide to replenish dying cells and regenerate damaged tissues. Also known as somatic (from Greek Σωματικóς, of the body) stem cells, they can be found in children, as well as adults.

A great deal of adult stem cell research has focused on clarifying their capacity to divide or self-renew indefinitely and their differentiation potential. Many adult stem cells may be better classified as progenitor cells, due to their limited capacity for cellular differentiation.

Nevertheless, specific multipotent or even unipotent adult progenitors may have potential utility in regenerative medicine. The use of adult stem cells in research and therapy is not as controversial as embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. In contrast with the embryonic stem cell research, more US government funding has been provided for adult stem cell research. Adult stem cells can be isolated from a tissue sample obtained from an adult. They have mainly been studied in humans and model organisms such as mice and rats.

Lineage

To ensure self-renewal, stem cells undergo two types of cell division (see Stem cell division and differentiation diagram). Symmetric division gives rise to two identical daughter cells both endowed with stem cell properties. Asymmetric division, on the other hand, produces only one stem cell and a progenitor cell with limited self-renewal potential. Progentiors can go through several rounds of cell division before terminally differentiating into a mature cell. It is believed that the molecular distinction between symmetric and asymmetric divisions lies in differential segregation of cell membrane proteins (such as receptors) between the daughter cells.

Treatments

Medical researchers believe that stem cell research has the potential to change the face of human disease. A number of current treatments already exist, although the majority of them are not commonly used because they tend to be experimental and not very cost-effective. Medical researchers anticipate being able to use technologies derived from stem cell research to treat cancer, parkinson's disease, spinal cord injuries, and muscle damage, amongst a number of other diseases, impairments and conditions. However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research.

Stem cells, however, are already used extensively in research, and some scientists do not see cell therapy as the first goal of the research, but see the investigation of stem cells as a goal worthy in itself. [1]

Controversy surrounding stem cell research

There exists a widespread controversy over stem cell research that emanates from the techniques used in the creation and usage of stem cells. Embryonic stem cell research is particularly controversial because, with the present state of technology, starting a stem cell line requires the destruction of a human embryo and/or therapeutic cloning. Opponents of the research argue that this practice is a slippery slope to reproductive cloning and tantamount to the instrumentalization of a human being. Contrarily, medical researchers in the field argue that it is necessary to pursue embryonic stem cell research because the resultant technologies are expected to have significant medical potential, and that the embryos used for research are only those slated for destruction anyway. The ensuing debate has prompted authorities around the world to seek regulatory frameworks and highlighted the fact that stem cell research represents a social and ethical challenge.

Key events in stem cell research
1960s - Joseph Altman and Gopal Das present evidence of adult neurogenesis, ongoing stem cell activity in the brain; their reports contradict Cajal's "no new neurons" dogma and are largely ignored
1963 - McCulloch and Till illustrate the presence of self-renewing cells in mouse bone marrow
1968 - bone marrow transplant between two siblings successfully treats SCID
1978 - haematopoietic stem cells are discovered in human cord blood
1981 - mouse embryonic stem cells are derived from the inner cell mass
1992 - neural stem cells are cultured in vitro as neurospheres
1995 - President Bill Clinton signs into law the Dickey Amendment which prohibited Federally appropriated funds to be used for research where human embryos would be either created or destroyed.
1997 - leukemia is shown to originate from a haematopoietic stem cell, the first direct evidence for cancer stem cells
1998 - James Thomson and coworkers derive the first human embryonic stem cell line at the University of Wisconsin-Madison.
2000s - several reports of adult stem cell plasticity are published
2003 - Dr. Songtao Shi of NIH discovers new source of adult stem cells in children's primary teeth[2]
2004-2005 - Hwang Woo-Suk claims to have created several human embryonic stem cell lines from unfertilised human oocytes. The lines are later shown to be fabricated
2005 - Researchers at Kingston University in England claim to have discovered a third category of stem cell, dubbed cord-blood-derived embryoniclike stem cells (CBEs), derived from umbilical cord blood. The group claims these cells are able to differentiate into more types of tissue than adult stem cells.
2001-2006 - President George W. Bush endorses the United States Congress in providing limited federal funding for embryonic stem cell research totalling approximately $100 million. At the same time, he also enacts laws that restrict federally funded stem cell research on embryonic stem cells to the already derived but dwindling cell lines. Bush also endorsed funding for a total of $250 million dollars for research on adult and animal stem cells.
July 19, 2006 - President George W. Bush vetoes H.R. 810, a bill that would have reversed the Clinton-era law which made it illegal for Federal money to be used for research where stem cells are derived from the destruction of an embryo.

Stem cell treatments

Medical researchers believe that stem cell treatments have the potential to change the face of human disease and alleviate suffering. A number of current stem cell treatments already exist, although they are not commonly used because they tend to be experimental and not very cost-effective. In the future, medical researchers anticipate being able to use technologies derived from stem cell research to treat cancer, spinal cord injuries, and muscle damage, amongst a number of other diseases and impairments.

However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which will only be overcome through years of intensive research and by gaining the acceptance of the public.

Furthermore, many technical difficulties remain which hinder the ultimate goals in stem cell therapeutics. Expanding stem cell populations extracted from patients remains a large problem. Also, even once these populations are expanded, implanted stem cells may not expand or grow efficiently enough to add enough corrective factor to be beneficial for treatment. These and other technical problems remain to be solved.

Current treatments

For over 30 years, bone marrow (adult) stem cells have been used to treat cancer patients with conditions such as leukemia and lymphoma. During chemotherapy, most growing cells are killed by the cytotoxic agents. These agents not only kill the leukemia or neoplastic cells, but also those which release the stem cells from the bone marrow. These are therefore removed before chemotherapy, and are re-injected afterwards.

Potential treatments

Brain Damage

Stroke and traumatic brain injury lead to cell death characterized by a loss of neurons and oligodendrocytes within the brain. Healthy adult brains contain neural stem cells that divide, and act to maintain stem cells numbers or become progenitor cells. In healthy adult animals, progenitor cells migrate within the brain and function primarily to maintain neuron populations for olfaction (the sense of smell). Interestingly, in pregnancy and after injury this system appears to be regulated by growth factors and can increase the rate at which new brain matter is formed. In the case of brain injury although the reparative process appears to initiate substantial recovery is rarely observed in adults suggesting a lack of robustness. Recently, results from research conducted in rats subjected to stroke suggested that administration of drugs to increase the stem cell division rate and direct the survival and differentiation of newly formed cells could be successful. In the study referenced below, biological drugs were administerd after stroke to activate two key steps in the reparative process. Findings from this study seem to support a new strategy for the treatment of stroke using a simple elegant approach aimed at directing recovery from stroke by potentially protecting and/or regenerating new tissue. The authors found that, within weeks, recovery of brain structure is accompanied by recovery of lost limb function suggesting the potential for development of a new class of stroke therapy or brain injury therapy in man. [1]

Spinal cord injury

A team of Korean researchers reported on November 25, 2004, that they had transplanted multipotent adult stem cells from umbilical cord blood to a patient suffering from a spinal cord injury and she can now walk on her own, without difficulty. The patient had not even been able stand up for the last 19 years. The team was co-headed by researchers at Chosun University, Seoul National University and the Seoul Cord Blood Bank (SCB). For the unprecedented clinical test, the scientists isolated adult stem cells from umbilical cord blood and then injected them into the damaged part of the spinal cord. [1] [2] [3] [4]

The Korean researchers have followed up on their original work. The original treatment was conducted in November 2004. On April 18, 2005, the researchers announced that they will be conducting a second treatment on the woman. [5] The researchers have followed up with a case study write-up on their work. It is located in the journal Cytotherapy. [6]

According to the October 7, 2005 issue of The Week, University of California researchers injected stem cells from aborted human fetuses into paralyzed mice, which resulted in the mice regaining the ability to move and walk four months later. The researchers discovered upon dissecting the mice that the stem cells regenerated not only the neurons, but also the cells of the myelin sheath, a layer of cells with which nerve fibers communicate with the brain (damage to which is often the cause of neurological injury in humans). [7]

In January 2005, researchers at the University of Wisconsin-Madison differentiated human blastocyst stem cells into neural stem cells, then into the beginnings of motor neurons, and finally into spinal motor neuron cells, the cell type that, in the human body, transmits messages from the brain to the spinal cord. The newly generated motor neurons exhibited electrical activity, the signature action of neurons. Lead researcher Su-Chun Zhang described the process as "you need to teach the blastocyst stem cells to change step by step, where each step has different conditions and a strict window of time."

Transforming blastocyst stem cells into motor neurons had eluded researchers for decades. The next step will be to test if the newly generated neurons can communicate with other cells when transplanted into a living animal; the first test will be in chicken embryos. Su-Chun said their trial-and-error study helped them learn how motor neuron cells, which are key to the nervous system, develop in the first place.

The new cells could be used to treat diseases like Lou Gehrig's disease, muscular dystrophy, and spinal cord injuries.

Muscle damage

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Adult stem cells are also apparently able to repair muscle damaged after heart attacks. Heart attacks are due to the coronary artery being blocked, starving tissue of oxygen and nutrients. Days after the attack is over, the cells try to remodel themselves in order to become able to pump harder. However, because of the decreased blood flow this attempt is futile and results in even more muscle cells weakening and dying. Researchers at Columbia-Presbyterian found that injecting bone-marrow stem cells, a form of adult stem cells, into mice which had had heart attacks induced resulted in an improvement of 33 percent in the functioning of the heart. The damaged tissue had regrown by 68 percent.

Heart damage

Several types of heart disease have been treated in clinical trials and therapy is commercially available. Patients such as Jeannine Lewis[8] and legendary Hawaiian crooner Don Ho[9]have traveled to Thailand to receive stem cell therapy for their heart disease.

Using the patient's own bone marrow derived stem cells or more recently, peripheral blood-derived stem cells, Dr. Amit Patel at the University of Pittsburgh, McGowan Institute of Regenerative Medicine has shown a dramatic increase in ejection fraction for patients with congestive heart failure. He works with many other countries such as Argentina, Uruguay, Ecuador, Greece, Japan, and Thailand where he has taught minimally invasive techniques for the treatment of non-ischemic (idiopathic) and ischemic heart failure.

In Malaysia as well, Stem Cell Therapy for the heart is well established (www.stemlife1.blogspot.com). Results are inline with results published in research papers.

Low blood supply

In December 2004, a team of researchers led by Dr. Luc Douay at the University of Paris developed a method to produce large numbers of red blood cells. The Nature Biotechnology paper, entitled Ex vivo generation of fully mature human red blood cells, describes the process: precursor red blood cells, called hematopoietic stem cells, are grown together with stromal cells, creating an environment that mimics the conditions of bone marrow, the natural site of red blood cell growth. Erythropoietin, a growth factor, is added, coaxing the stem cells to complete terminal differentiation into red blood cells.

Further research into this technique will have potential benefits to gene therapy, blood transfusion, and topical medicine.

Baldness

Hair follicles also contain stem cells, and some researchers predict research on these follicle stem cells may lead to successes in treating baldness through "hair multiplication," also known as "hair cloning," as early as 2008. This treatment is expected to work through taking stem cells from existing follicles, multiplying them in cultures, and implanting the new follicles into the scalp. Later treatments may be able to simply signal follicle stem cells to give off chemical signals to nearby follicle cells which have shrunk during the aging process, which in turn respond to these signals by regenerating and once again making healthy hair. Hair Cloning Nears Reality as Baldness Cure (WebMD Nov. 2004)

Missing teeth

In 2004, scientists at King's College London discovered a way to cultivate a complete tooth in mice [10] and were able to grow them stand-alone in the laboratory. Researchers are confident that this technology can be used to grow live teeth in human patients.

In theory, stem cells taken from the patient could be coaxed in the lab into turning into a tooth bud which, when implanted in the gums, will give rise to a new tooth, which would be expected to take two months to grow. [11] It will fuse with the jawbone and release chemicals that encourage nerves and blood vessels to connect with it. The process is similar to what happens when humans grow their original adult teeth.

Its estimated that it may take until 2009 before the technology is widely available to the general public, but the genetic research scientist behind the technique, Professor Paul Sharpe of King's College, estimates the method could be ready to test on patients by 2007 [12]. His startup company, Odontis, fully expects to offer tooth replacement therapy by the end of the decade.

Deafness

There has been success in regrowing cochlea hair cells with the use of stem cells. [13]

Blindness and Vision Impairment

Since 2003, researchers have successfully transplanted retinal stem cells into damaged eyes to restore vision. Using embryonic stem cells, scientists are able to grow a thin sheet of totipotent stem cells in the laboratory. When these sheets are transplanted over the damaged retina, the stem cells stimulate renewed repair, eventually restoring vision [14]. The latest such development was in June of 2005, when researchers at the Queen Victoria Hospital of Sussex, England were able to restore the sight of forty patients using the same technique. The group, led by Dr. Sheraz Daya, was able to successfully use adult stem cells obtained from the patient, a relative, or even a cadaver. Further rounds of trials are ongoing [15].

In April 2005, doctors in the UK transplanted corneal stem cells from an organ donor to the cornea of Deborah Catlyn, a woman who was blinded in one eye when an acid was thrown in her eye at a nightclub. The cornea, which is the transparent window of the eye, is a particularly suitable site for transplants. In fact, the first successful human transplant. The transplant carried out in 1905 by Dr. Eduard Zirm. The recipient was Alois Gloger, a labourer who had been blinded in an accident. The cornea has the remarkable property that it does not contain any blood vessels, making it relatively easy to transplant. The majority of corneal transplants carried out today are due to a degenerative disease called keratoconus which causes vision imapairment and has no known cure even after corneal transplant. It is hoped that stem cell research will one day provide a cure to such debilitating corneal disorders.

As more research yields increasingly precise techniques, stem cell transplantation to restore vision may become viable on a large. The success rate of the procedure is currently from 20 to 70 percent [16], and further stem cell research is required.

ALS (Lou Gehrig's Disease)

In the April 4th, 2001 edition of JAMA (Vol. 285, 1691-1693) [17], Drs. Gearhart and Kerr of Johns Hopkins University used stem cells to cure rats of an ALS-like disease. The rats were injected with a virus to kill the spinal cord motor nerves related to leg movement. Dr. Gearhart and Dr. Kerr then injected the spinal cords of the rats with stem cells. These migrated to the sites of injury where they were able to regenerate the dead nerve cells restoring the rats which were once again able to walk.

Some scientists see shift in stem cell hopes

It was reported in the New York Times (14th August 2006), by Nicholas Wade, that some scientists see a shift in stem cell hopes. Several mentioned that the main role of stem cells was in research. Many no longer see cell therapy as the first goal of the research, parting company with those whose near-term expectations for cell therapy remain high. [18]

Thomas M. Jessell, a neurobiologist at Columbia University said that:

"Many of us feel that for the next few years the most rational way forward is not to push stem cell therapies". [19]

Controversy

There is wide spread controversy over the use of embryonic stem cells. This controversy is over the technique used to create new embryonic stem cell lines, which often requires the destruction of the blastocyst. While the American government does not fund embyronic stem cell research that uses new lines, it does fund embryonic stem cell research that uses existing stem cell lines. The argument for this is that creating embryonic stem cells with existing lines does not require the destruction nor the use of a human embryo. Nevertheless, the lack of harsher regulations from the federal government has led states to further restrict the use of embryonic stem cells in research and medicine.

Stem cell use in animals

Horses

Stem cell treatment has begun on horses, mainly to treat injuries to the tendons, ligaments, and joints of sport horses or racehorses. Fat is harvested from the tail head and processed, and an animal may receive treatment within three days after the sample is taken. Injuries that may be treated include Degenerative Joint Disease, soft-tissue injuries, Osteochondrosis, fractures, and sub-chonral bone cysts. Currently, research is also being preformed on stem cell application in laminitis and COPD.[20]

Dogs

There is currently research being preformed on the usefulness of stem cells in canine lameness.