Stem Cell Therapy

Stem Cell Therapy

Stem cells are cells that have the potential to develop into many different or specialized cell types. Stem cells can be thought of as primitive, "unspecialized" cells that are able to divide and become specialized cells of the body such as liver cells, muscle cells, blood cells, and other cells with specific functions. Stem cells are referred to as "undifferentiated" cells because they have not yet committed to a developmental path that will form a specific tissue or organ. The process of changing into a specific cell type is known asdifferentiation.

What are the different types of stem cells?

Embryonic stem cellsFetal stem cellsAdult stem cellsPeripheral blood stem cellsUmbilical cord stem cellsInduced pluripotent stem cells

During the early stages of embryonic development the cells remain relatively undifferentiated (immature) and appear to possess the ability to become, or differentiate, into almost any tissue within the body. For example, cells taken from one section of an embryo that might have become part of the eye can be transferred into another section of the embryo and could develop into blood, muscle, nerve, or liver cells.Cells in the early embryonic stage are totipotent (as see) and can differentiate to become any type of body cell. After about seven days, the zygote forms a structure known as a blastocyst, which contains a mass of cells that eventually become the fetus, as well as trophoblastic tissue that eventually becomes the placenta. If cells are taken from the blastocyst at this stage, they are known aspluripotent, meaning that they have the capacity to become many different types of human cellEmbryonic stem cellsThe embryo is referred to as a fetus after the eighth week of development. The fetus contains stem cells that are pluripotent and eventually develop into the different body tissues in the fetus.

Fetal stem cellsAdult stem cells present in all humans in small numbers. The adult stem cell is one of the class of cells that we have been able to manipulate quite effectively in the bone marrow transplant arena over the past 30 years. These are stem cells that are largely tissue-specific in their location. Rather than typically giving rise to all of the cells of the body, these cells are capable of giving rise only to a few types of cells that develop into a specific tissue or organ. They are therefore known asmultipotentstem cells. Adult stem cells are sometimes referred to as somatic stem cells.

Adult stem cells

Peripheral blood stem cellsMost blood stem cells are present in the bone marrow, but a few are present in the bloodstream. This means that these so-calledperipheral blood stem cells(PBSCs) can be isolated from a drawn blood sample.Red blood cellscarry oxygen around the body and give the blood its color.Plateletsare cell fragments that stop a person from bleeding and help the body to clot and heal when it is cut.Granulocytesare a type of white blood cell that helps fight bacterial infection.Lymphocytesare a type of white blood cell that is part of the immune system, help fight other infections, and also may be involved in protection againstcancer.All of these very different cells with very different functions are derived from a common, ancestral, committed blood-forming (hematopoietic), stem cell.

Blood from the umbilical cord contains some stem cells that are genetically identical to the newborn. Like adult stem cells, these are multipotent stem cells that are able to differentiate into certain, but not all, cell types. For this reason, umbilical cord blood is often banked, or stored, for possible future use should the individual require stem cell therapy.Umbilical cord stem cells

A relatively recent breakthrough in stem cell research is the discovery that specialised adult cells can be reprogrammed into cells that behave like embryonic stem cells, termedinduced pluripotent stem cells(iPSCs).iPSCs are valuable aids in the study of disease development and drug treatment, and they may have future uses in transplantation medicine. Further research is needed regarding the development and use of these cells.

Induced pluripotent stem cells

ADVANTAGES OF STEM CELL THERAPY

A Second Chance:Patients are given another chance at life when the options available through conventional means are exhausted or fail to result in a reasonable quality of life.Regenerate all areas of the body Repairing damaged or diseased tissues Curing such degenerative diseases such as Alzheimers disease.Reverse the effect of aging or slow the aging process.Prolong our livesNatural:Regenerative solutions replace damaged cells and tissue by making the most of the body's natural regenerative potential, not just implant a temporary or artificial fix.Safe and Effective:Because the Adult Stem Cells are derived directly from the patient's own body, there is virtually no possibility for rejection, as compared to donor replacement organs and blood transfusions.Positive Side Effects:Stem cells also behave like beacons that alert the body to send its own regenerative resources to the site and reactivate the healing process in situations where the body would not have done so voluntarily.Proven Results:Clinical results thus far have proven positive. Remarkably, no patient has responded negatively to the cells and the small percentage of patients who did not respond to treatment showed no negative side effects.The Earlier a Patient is Treated, the Better the Success Rate:Receiving treatmentnowwill offer a greater result thanlater. Just as with other medical treatments, it is always better to treat a serious progressive disease sooner than wait until symptoms and complications are more advanced.Benefits from Regenocyte

Adult stem cells offer the possibility of a renewable source of replacement cells and tissues to treat a myriad of diseases, conditions and disabilities.It provides medical benefits in the fields of therapeutic cloning and regenerative medicine.It provides great potential for discovering treatments and cures to a plethora of diseases including Parkinson's disease, schizophrenia, Alzheimer's disease, cancer, spinal cord injuries, and diabetes.Limbs and organs could be grown in a lab from stem cells and then used in transplants or to help treat illnesses.It will help scientists to learn about human growth and cell development.Scientists and doctors will be able to test millions of potential drugs and medicine, without the use of animals or human testers. This necessitates a process of simulating the effect the drug has on a specific population of cells. This would tell if the drug is useful, or has any problems.Stem cell research also benefits the study of development stages that cannot be studied directly in a human embryo, which sometimes are linked with major clinical consequences such as birth defects, pregnancy-loss, and infertility. A more comprehensive understanding of normal development will ultimately allow the prevention or treatment of abnormal human development.Another advantage is that it holds the key to reversing the effects of aging and prolonging our lives. It has already found many treatments that help in slowing the aging process, and a bonus of further research is a possible 'cure' for aging, altogether.

An advantage of the usage of adult stem cells to treat disease is that a patient's own cells could be used to treat a patient. Risks would be quite reduced because patients' bodies would not reject their own cells.Embryonic stem cells can develop into any cell types of the body, and may then be more versatile than adult stem cells.Generate healthy cells to replace diseased cells (regenerative medicine).Stem cells can be guided into becoming specific cells that can be used to regenerate and repair diseased or damaged tissues in people.People who might benefit from stem cell therapies include those with spinal cord injuries, type 1 diabetes, Parkinson's disease, Alzheimer's disease, heart disease, stroke, burns, cancer and osteoarthritis.Stem cells may have the potential to be grown to become new tissue for use in transplant and regenerative medicine. Researchers continue to advance the knowledge on stem cells and their applications in transplant and regenerative medicine.Test new drugs for safety and effectiveness.Before using new drugs in people, some types of stem cells are useful to test the safety and quality of investigational drugs. This type of testing will most likely first have a direct impact on drug development for cardiac toxicity testing.

DISADVANTAGES OF STEM CELL THERAPY

DESTRUCTION OF LIFE. The use of embryonic stem cells involves the destruction of blastocysts formed from laboratory fertilized human eggs. For those people who believe that life begins at conception, the blastocyst is a human life and destroy it is immoral and unacceptable. This has been the issue of debate among the pro life, religious group and scientific community. That the benefits should not outweigh the issue of ethics. That the human life should not be compromised.UNKNOWN LONG TERM-EFFECTS. Like any other new technology, it is also completely unknown what the long term effects of such interference with nature could materialize.ADDITIONAL RISK TO THE BODY. According to a new research, it was used on heart disease patients. It was found that it can make their coronary arteries narrower. It is difficult to tell how these cells will take. Pluripotent embryonic stem cells often form teratomas (a tumor-like, cancerous mass, resembling a self-fertilized cell, differentiated but not fertilized). Teratomas have been shown to form when embryonic stem cells are injected into animals. Subsequently in China, a man with Parkinsons disease was treated with human embryonic stem cells which developed into a cancerous tumor (teratoma) in his brain. The man died from this tumor, even though the treatment was intended to help him, not kill him. As an increasing number of researchers have observed, the power of embryonic stem cells is also the source of their potential peril. (Bohlin RG, The Continuing Controversy Over Stem Cells, 2005, online publication).NOT AN ABSOLUTE SOLUTION FOR CURE. Embryonic stem cells may not be the solution for all ailments. A disadvantage is that they are prespecialized; for instance, blood stem cells make only blood and brain stem cells make only brain cells. Finally there are still many unknowns associated with adult stem cells. These cells may still harbor genetic defects in that the targeted disease may also be present in the genes of these cells.RISK FOR REJECTION. These are derived from embryos that are not a patients own and the patient body may reject them. DIFFICULT TO HARVEST. This goes to the adult stem cells which is believed harder to find and harvest from the host. Adult stem cells are present in mature tissues, but isolating and harvesting them is a very tough procedure. These cells also have limited flexibility and cannot be reprogrammed to transform themselves into any type of cell in the body.DO NOT HAVE A LONG STORAGE LIFE. Furthermore adult stem cells do not have a long storage life. They may not thrive as much as their embryonic counterparts in laboratory cultures. Hence it becomes difficult to maintain these cells in cultures for longer periods of time.DIFFICULT TO CONTROL. Embryonic stem cells are difficult to control and it may take many attempts before researchers are able to derive the desired cell line from them.According to the London based Institute of Science in Society, researchers have drawn the following conclusions:Due to the number and severity of the technical challenges remaining to be solved before the initiation of large scale clinical trials, embryonic stem cells are not likely to be part of routine clinical practice in the foreseeable future.Exacerbating health inequalities: another objection to hES cell research is that it will be a very costly procedure, even if it succeeds, and will exacerbate the global inequalities in access to healthcare. Populations in developing countries have more urgent diseases to fight, and they will be that much more disadvantaged if large portions of the available funds are diverted towards developing hES cell technology by the hype and misinformation surrounding it.The use of embryonic stem cells involves the destruction of blastocysts formed from laboratory-fertilized human eggs. For those people who believe that life begins at conception, the blastocyst is a human life and to destroy it is immoral and unacceptable.

Like any other new technology, it is also completely unknown what the long-term effects of such an interference with nature could materialize.Embryonic stem cells may not be the solution for all ailments.According to a new research, it was used on heart disease patients. It was found that it can make their coronary arteries narrower.

A disadvantage is that they are prespecialized; for instance, blood stem cells make only blood, and brain stem cells make only brain cells.

These are derived from embryos that are not a patient's own and the patient's body may reject them.

Now on the darker side, which is supported by the naysayers, stem cell research is unethical. They say that the benefits should not shroud the issue of ethics. Cloning is vehemently objected to by those who are against it. It has also been said to be declared illegal in some countries. Human life shouldn't be compromised for any purposes, even if it is in the form of an embryo. Some believe that life does not begin until birth, but those who argue against it say that embryos are where life begins and hence using them for research is like killing.

t is hard to clearly demarcate the advantages and disadvantages of stem cell research. But the fact remains and no one can deny it, that it has ushered in, a significant development in the field of medical science. It is certainly going to benefit the human race, even if there would be some who would try and exploit the darker side, or misuse its benefits. After all, you won't see the silver lining if there wasn't a dark cloud.

Disadvantages of Adult Stem Cell Research1. The primary disadvantage of adult stem cell research is that although these cells are available from the bone marrow of adults, they are limited in number. There are only so many cells that can be harvested from an individual, forcing scientists to make judicious use of the available quantity.2. Furthermore adult stem cells do not have a long storage life. They may not thrive as much as their embryonic counterparts in laboratory cultures. Hence it becomes difficult to maintain these cells in cultures for longer periods of time.3. Another disadvantage is that the harvesting procedure itself is difficult. Adult stem cells are present in mature tissues, but isolating and harvesting them is a very tough procedure. These cells also have limited flexibility and cannot be reprogrammed to transform themselves into any type of cell in the body.4. Finally there are still many unknowns associated with adult stem cells. These cells may still harbor genetic defects in that the targeted disease may also be present in the genes of these cells.1. Embryonic stem cells are difficult to control and it may take many attempts before researchers are able to derive the desired cell line from them.2. The use of embryonic stem cells involves the destruction of 5 to 7-day-old embryos, which has raised moral and ethical issues amongst the public.3. There is also a risk of immunogenic reaction as stem cells from a random embryo donor are more likely to face rejection after transplantation.4. These cells may also trigger cancer or tumor formation because there are so many factors that are yet to be studied in detail.

Disadvantages of Embryonic Stem Cell ResearchAmong other disadvantages, embryonic stem cells are highly unstable. They have not yet been through Mother Natures test, which is to create a human being. It is a well established fact that 50 to 75% of all human embryos fail to develop into a human being and spontaneously abort, due either to inborn errors such as a genetic mutation or to problems implanting. More pregnancies spontaneously abort than result in the successful birth of a child. Even considering the conservative estimate of 50% nonviability, when working in a laboratory with an embryo, it is impossible to know from which 50% any particular embryo has been selected. If embryonic stem cells happen to come from the 50% of embryos that would have proven to be nonviable (if allowed to develop normally), then those same inborn errors will be transferred to the patient receiving the stem cells. Clearly, this could cause more harm than good. Ethico-Legal MatterADULT STEM CELLSEMBRYONIC STEM CELLSINDUCED PLURIPOTENT STEM CELLSETHICAL CONCERNSNo major ethical concerns have been raised To acquire the inner cell mass the embryo is destroyedRisk to female donors being consentediPS cells have the potential to become embryos if exposed to the right conditionsUpdatesStem cell type Where do we get them? What can they do? Current research uses Ready for the clinic? Advantages What we dont know Embryonic stem cells (ESCs)

Early stage embryo called a blastocyst Make all the different types of cells in our body Understanding how our bodies develop from a fertilized egg; Investigating how to produce different types of specialised cell The first clinical trials are now beginning, focussed on treating eye disorders; these are early stage safety trials.Can produce all the different types of cells in the body Can self-renew (copy themselves) almost forever, so large supplies can be made Still learning how to fully control differentiation of these cells Some groups have concerns on ethical or religious grounds Tissue stem cells (e.g. skin, blood)

Tissues of the adult body

Make only the types of cells that belong in their own tissue, e.g. skin stem cells make only types of skin cells, they do not make brain or blood cells Understanding how adult tissues are made and maintained Improving our understanding of diseases affecting adult tissues, including cancer

Skin and blood stem cells have been in use for a number of years for skin grafts and bone marrow transplants

Already partly specialised, which can make it more straightforward to obtain the particular specialised cell type required

Still learning how to multiply, control and use different types of tissue stem cells Treatments for blood diseases, severe burns and some types of corneal damage haveUmbilical cord blood stem cells (a type of tissue stem cell)

The umbilical cord after the birth of a baby

Make the different types of cells found in the blood

Understanding how blood stem cells work

Mainly used to treat children with blood disorders, primarily leukaemia; although adults can sometimes be treated, this is limited because only a small number of stem cells can be obtained from a cord Not yet proven for any other applications Can be frozen and stored

Need to know how to multiply cord blood stem cells Only proven uses are for blood disorders; studies suggesting these cells can be used to make non-blood-related types of cells have not been widely reproduced Mesen-chymal stem cells (a type of tissue stem cell)

Bone marrow Make cells of the skeletal tissues: bone, cartilage, fat Support blood stem cells to make new blood cells Not proven to make any other types of cells

Understanding how these cells contribute to making and maintaining tissues

Some clinical trials are underway for cartilage and bone repair, for supporting repair of blood vessels after heart attacks, and for other unrelated treatment tyes. Mesenchymal stem cells can be easily obtained from the bone marrow of patients MSCs can be used for efficient generation of skeletal tissues in the body

Cells from a variety sources have been termed MSCs it has not been established whether these cells are all the same or different

Induced pluripotent stem cells (iPS cells)

Made in the lab from specialized adult cells, for example skin cells

Behave very like embryonic stem cells make all types of cells in the body

Can be made from patients and used to produce cells that act as a model disease in the laboratory for studying diseases and testing new drugs

Not yet!

Could provide patient-specific treatment

Not yet established how reprogramming works Properties of cells need further comparison with embryonic stem cells As with ES cells, we are still learning how to fully control these cells to ensure they make the cells we want in a way that will be safe for clinical use

http://www.eurostemcell.org/factsheet/stem-cell-research-therapy-types stem-cells-and-their-current-useshttp://www.medicinenet.com/stem_cells/article.htmAdistem Technology www.buzzle.com,www.eHow.comwww.onlinewellnesscommunity.com REFERENCE