Yes, adult or somatic stem cells have been used for some time to treat disease. For example, blood stem cells created in the bone-marrow are used in “bone-marrow transplant" as a common therapy for various blood based diseases such as leukemia and aplastic anemia. Organ transplantation also uses stem cell technology.

In spinal cord injury and Parkinson’s disease, the body is unable to naturally heal the damaged axons and dopamine-producing neurons of the spinal cord and brain, respectively. In spinal cord injury, loss of muscle and sensory function is seen below the site of the injury. In Parkinson’s disease, involuntary movements and tremors result from the damaged neurons in the brain.

Some diseases, such as Parkinson's or diabetes, are caused by cell defects. Replacing the faulty cells with healthy ones grown from stem cells offers the hope of lifelong treatment. Similarly, injecting healthy cells to replace damaged or diseased cells could shore failing hearts and other organs, in theory, up.

Not yet. Although embryonic stem cell research has shown great potential, the field is still very new; human embryonic stem cells were first identified in 1998. Moreover, in the US and some other countries, progress has been slowed by funding restrictions and political controversies.

Using stem cells to combat cancer is an interesting prospect. Research into this area is very new and novel. One research group found that they could use mesenchymal stem cells to deliver a cancer-toxic protein to developing tumors. Studies like this combine stem cells and gene therapy.

Blood cells grow in the same way as other human cells. They are developed in the bone marrow from a parent cell known as a “stem cell.” These stem cells begin to divide and mature until they are fully developed, forming all the different types of blood cells: white blood cells, platelets and red blood cells. Stem cells are usually found inside the bone marrow spaces of large bones, however, they can also travel from one bone to the other by way of the blood system.

Stem cells from a baby are a perfect match only for the baby or for an identical twin, and may be a very good match for a sibling. They can be used for a relative or friend if their cells closely match the baby's cells.

Doctors have been using adult stem cells, such as the blood-forming type in bone marrow (called hematopoietic stem cells), to perform bone marrow transplants for over 40 years. Similar techniques have since been developed for treating leukemia, lymphoma and several inherited blood disorders. Recent studies have shown that adult stem cells may be able to treat a wider range of diseases than previously thought.

Tooth stem cells can potentially be used to treat conditions in first or second degree blood relatives (siblings, parents, grandparents, uncles, and aunts) in addition to the donor. Please see previous question.

Hematopoietic stem cells (HSCs), present in the bone marrow and precursors to all blood cells, are currently the only type of stem cells commonly used for therapy. Doctors have been transferring HSCs in bone marrow transplants for more than 40 years. Advanced techniques for collecting or "harvesting" HSCs are now used to treat leukemia, lymphoma and several inherited blood disorders.

Stem cells therapies are part of what are called "cellular therapies", which are techniques that rely either on the regeneration unhealthy cells or on the replacement of unhealthy cells by healthy cells. Even though the majority of cellular therapies are currently experimental, certain techniques are currently in practice, such as bone marrow and skin grafts.

Stem cells have the potential to develop into many different cell types in the human body. The cells can theoretically divide and multiply without limit to replenish certain cells as long as the person is still alive. During the division of a stem cell, each new cell has the potential to remain a stem cell or become a different kind of cell with a specific function. Examples include muscle cell, brain cell, or a red blood cell.

Click here for a list of the types of diseases and conditions that stem cells can help or that therapies are in the process of being developed for.

Embryonic stem cell research will help to understand the origin of inherited human diseases including birth defects, neurodegenerative diseases and cancer. Stem cells also could be used to develop safer and more effective new drugs. often overlooked benefit of studying embryonic stem cells is that we currently have no good way of studying early human development.

Psychostimulant medications, including methylphenidate (Ritalin®) and amphetamines (Dexedrine®, Dextrostat®, and Adderall®), are by far the most widely researched and commonly prescribed treatments for ADHD. Numerous short–term studies have established the safety and efficacy of stimulants and psychosocial treatments for alleviating the symptoms of ADHD.

The first step in dietary management of inflammatory bowel disease is fat restriction. Fat prolongs the time food spends in the stomach which tends to promote nausea. There can also be undesirable interactions with fats and the bacteria of the intestine. The second step in using diet as therapy for this condition is to use a protein source with which the patient is inexperienced. Such a novel diet is considered "hypoallergenic" and removes any immunological stimulation by dietary properties.

When stem cells are used for the treatment of blood cancers, patients have (typically) been treated with chemotherapy and/or radiation to destroy the cancer cells invading the body. Stem cells are then given (or transplanted) to regenerate the patients' blood and immune systems. Whether the bone marrow has been damaged by medical treatment, such as chemotherapy or radiation, or by the disease itself, a stem cell transplant usually becomes necessary.

The uses for stem cells in different treatment therapies are increasing every day. In addition to the already documented 80 to 90 present uses for stem cells, researchers are anticipating their use in treatments for diabetes, heart disease, stroke, and muscular dystrophy. Repair of spinal cord injuries, blood vessel growth, treatment of Alzheimer’s and Parkinson’s disease are other areas of anticipated use.

bull; Other than embryonic stem cells, stem cells can be found in the fetal liver, bone marrow and yolk sac, among other areas of the body. (Put link to yolk sac diagram here and also in next question) Umbilical cord blood is taken from the cord attached to the placenta. This source of blood is a major source of hematopoietic stem cells, but also consists of other types of stem cells.

There are several stem cells found after the development process of embryonic stem cells begins. The most studied of these cells are those that migrate to the bone marrow. These are the hematopoietic stem cells first detected in the yolk sac and the embryo from a stem cell referred to as the hemangioblast. The blood vessels needed by the hematopoietic stem cells are also formed from the hemangioblasts and are referred as the angioblast.

Stem cells are present within various organs of the adult body and are called ‘adult stem cells’. The prototypical adult stem cell, the hematopoietic stem cell, is found in the bone marrow. The hematopoietic stem cells have the genetic 'blueprint' for forming all of the blood and immune cells. Thus, their main function is to be available to respond to infection and blood loss, while replacing cells on a day-to-day basis.

Stem cells have been reported in the: brain, termed neural stem cells, gut, root of teeth, skin, heart, kidney and teeth. Scientists are still finding different stem cells.

Some researchers believe that cancer is maintained by a few cancer stem cells, while others believe that it could be a normal stem cell “gone wrong”. Research on any type of stem cells is likely to lead to a better understanding of cancer stem cells. Once this information is fully understood, drugs can be developed to kill the cancer stem cells and thereby improve cancer treatment. Pardal R et al. Nature Reviews 2003;3: 895-902; Reya T et al.