About Stem Cells Medical and Scientific Overview of Stem Cells What are Stem Cells? Stem Cells are the original building blocks of life, the body’s founder cells which differentiate into all the specialized cells that make up the human body (skin, blood cells, muscle, bones, nerves etc). Where are Stem Cells Found?		Medical & Scientific Overview      Medical Opinions & Useful links      News & Press Articles

Embryo The richest and most abundant source of stem cells is found in an embryo. The proposed use of stem cells from this source is what has made stem cells so controversial, as it involves the termination of a potential life. It is the use of these embryonic stem cells that President George Bush has vetoed in the United States. Netcells is not involved in any form of embryonic stem cell harvest, storage, research or therapies. Umbilical Cord Stem cells are abundant in the umbilical cord and placenta. This makes the collection of umbilical cord blood a once-in-a-lifetime opportunity that is free of moral, ethical or religious concerns, as the umbilical cord and placenta are routinely discarded at birth. Adult Stem cells are also found in adults including bone marrow, peripheral blood, neural tissue, adipose (fat) tissue, skin and liver. These stem cells are active in repairing and maintaining our tissues and organs through out our lives. They are however, small in number and very difficult to isolate. The only adult stem cells used in therapy are those from the bone marrow and peripheral blood that are used in bone marrow transplants.

Diseases Treatable with Stem Cells

Current Applications

Umbilical cord blood is rich in haematopoietic stem cells which means they have the ability to evolve into all the specific cell types in the blood and immune system. Thus, umbilical cord blood stem cells are used to treated blood and blood related diseases. Two other sources of stem cells can also be used – the bone marrow of an adult or the peripheral blood of an adult. The treating doctor will decide which source of stem cells to use depending on several factors, including but not limited to: the degree of match between donor and patient, the expected speed of engraftment and the amount of time available to search for a matching donor. The following table lists diseases for which haematopoietic stem cells are a standard treatment. For some diseases they are the only therapy and for others, they are employed when front-line therapies have failed or the disease is very aggressive.

Leukemias(Leukemia is a cancer of the blood immune system, whose cells are called leukocytes or white cells) Myelodysplastic Syndromes ( Myelodysplasia is sometimes called pre-leukemia) Lymphomas ( Lymphoma is a cancer of the leukocytes that circulate in the blood and lymph vessels) Anemia (Anemia’s are deficiencies or malformations of red cells) Inherited Platelet Abnormalities (Platelets are small blood cells needed for clotting) Myeloproliferative Disorders Inherited Immune System Disorders Metabolic Disorders Other cancers (Not originating in the blood system)

Future link to more comprehensive list in Health Professionals section.

Haematopoietic stem cells can be retrieved from 3 types of donors:

• The patient themselves (autologous transplant)
• A related donor i.e. a family member
• An unrelated donor (allogenic transplant)

Autologous transplantation

Autologous transplantation means that the donor and the recipient is the same person. This type of transplantation refers to the situation where the child’s own stem cells are used for themselves. It needs to be noted that autologous transplantation cannot be used in the treatment of inherited disorders. The reason being that the genes that code for the inherited disorder are carried in every cell i.e. they will also be found in the person’s stem cells. So, we cannot return cells containing genes for a disorder back into the person after we have treated them for the disorder. In that case, an allogenic donor will be used. Traditionally, autologous transplantation was not done for acute leukaemia’s in children. However, views on this subject are changing and autologous transplantations are being tried in childhood leukaemia.

Allogenic transplantation

This type of transplant is a transplant between two genetically non-identical individuals. These individuals may be related family members or completely unrelated. Allogenic transplants (allograft) may be used in the treatment of inherited and non- inherited disorders. Before doing an allograft, the recipient needs to find a matching donor.

HLA matching necessary for transplants

Prior to allogenic stem cell transplantation, HLA – type matching needs to take place. A 6/6 HLA match is necessary for bone marrow and peripheral blood stem cell transplants. Due to the “immature immunity” of umbilical cord blood only a 3-4/6 HLA match is necessary. The implications of this are:

• The chances of finding a donor are significantly increased, with a 1:4 chance of a sibling being a match and 1:8 chance for parents
• Adult patients can receive a combination of multiple, mismatched cord blood units.
• Graft Versus Host Disease is less severe with cord blood than with bone marrow transplants.

The amount of stem cells necessary for transplantation

Currently, the average number of stem cells collected from an umbilical cord blood collection will treat up to a 50kg person. The optimal dose is about 20 million nucleated cells per kilogram of body weight. As stated above, multiple, mismatched cord blood units can be used simultaneously in a transplant for an individual over 50kg in weight. The use of cord blood for adults is being enhanced by expanding the number of stem cells in vitro. Companies are developing techniques to rapidly grow stem cells in a laboratory environment and these are being used in clinical trials.

Long term viability of frozen cord blood

Thus far it has been proven that there is a recovery of over 90% of viable stem cells after thawing units that have been cryogenically frozen for 15 years.

Future Applications

The future medical potential of stem cells is what has made this subject so fascinating, yet controversial. Significant research is being undertaken worldwide in stem cell therapies including:

• Cardiac muscle regeneration
• Bone repair in non- union fractures
• Diabetes, Type 1
• Auto-immune diseases
• Nerve cell repair e.g. Cerebral palsy, Alzheimer’s disease, Parkinson’s, spinal cord injury, stroke recovery
• Organ repair e.g. liver and kidney

Who Can Use the Stem Cells?

Stem cells represent a perfect match for the child whose cord blood stem cells have been stored, with no risk of rejection. There is also an excellent possibility that the stem cells will be a suitable match for family members and/or close relatives:

• a sibling (1 in 4)
• a parent (1 in 8)
• a grandparent (1 in 32)

Chances of Needing the Stem Cells?

Hopefully they will never be needed and should be regarded as an extra form of medical insurance. The diseases that stem cells can currently treat are not common and therefore, the chances of using the cells are thankfully rare. Studies in the US have been done to calculate the lifetime probability (age 0-70) that an individual will undergo a stem cell transplant. They reported that 1:435 people will receive their own stem cells for treatment; 1:400 persons will receive someone else’s stem cells; and the combined total number of stem cell transplants will be 1:217 persons. With all the current research being undertaken, it is likely that retrievals will increase in the future, as more diseases become treatable through stem cell therapy.

Reasons to Consider Storing your Baby’s Stem Cells

• Family history of certain illnesses especially haematological (blood) cancers, inherited blood disorders and inherited immune deficiencies.


• Sibling with disease treatable by stem cell transplant.


• Families of African origin and mixed race marriages, as it is extremely difficult to find suitable donors, as they are seriously under-represented in public banks.


• Form of medical insurance, to give you extra peace-of-mind. You hope you never need them, but if you do, they are available.


• Question of affordability. As with all things, cost is important. Storing you baby’s stem cells is not cheap and cost anywhere between R12,000 – R20,000, inclusive of 20 – 25 years storage. If you do speak to your doctor and there is a negative response, it is because some doctors are of the opinion that this is a waste of money, because the chances of needing the stem cells are low. You must however remember that as medical science progresses, more and more diseases will become treatable with stem cells.
  

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