Information

Stem Cells

What is Cord Blood?

Cord Blood (sometimes also called "placental blood") is found in the baby's umbilical cord and is normally discarded, along with the placenta, as medical waste after the birth. Most importantly, cord blood is the baby's blood, rather than the mother's and is rich in stem cells.

What are stem cells?
Stem cells are regarded as the 'building blocks' or "master cells" of the blood and immune system as well as other types of cells and tissues. They are "unspecialised" cells, which can develop into specialised cells, such as red blood cells or other specific body tissue to treat specific diseases.

They are "multipotent", meaning they can give rise to many different types of cell in the body. Research is also being conducted into making them "pluripotent", which would allow a greater number of treatments possible, since they would be able to give rise to just about any type of cell in the body.

There are currently three main sources of stem cells:

• Bone Marrow (also known as adult stem cells)
• Peripheral Blood (i.e. the blood which circulates around your body)
• Umbilical Cord Blood

Research is also being conducted into embryonic stem cells, which is the subject of major debate around the world. There is no connection between this research and the collection and storage of your baby's stem cells, except for the fact that storage of a baby's stem cells could obviate the need for embryonic stem cell development in that child's later life.Research is also being conducted into embryonic stem cells, which is the subject of major debate around the world. There is no connection between this research and the collection and storage of your baby's stem cells, except for the fact that storage of a baby's stem cells could obviate the need for embryonic stem cell development in that child's later life.

Why are cord blood stem cells different and better than the other sources?

Stem cells extracted from cord blood are the "youngest" type of stem cells and, as a result, have therapeutic advantages over those collected through other means.

They are less likely to contain DNA abnormalities (for example, caused by sunlight and other toxins) and are less likely to be rejected in transplantations, even if not an exact match. On a practical level, the collection of cord blood has fewer risks, such as those associated with the use of a general anaesthesia when harvesting bone marrow.

Furthermore, they are immediately available for use if they are required for treatment, which could improve the chances of effective treatment by minimising the chances of disease progression while a suitable bone marrow donor is located.

What diseases can be treated with stem cells today?

Over the past 20 years, since the procedure was developed, stem cells have been used in the treatment of many different cancers, immune deficiencies and genetic disorders. They restore function to the blood-making and immune systems, which are especially valuable if these, have been damaged through illness or other treatments (such as chemotherapy). These diseases have, until recently, mainly been treated by bone marrow stem cell and peripheral blood stem cell transplantation, since umbilical cord blood stem cells have only been stored since the early 1980s.

To date, more than 45 disorders have been treated with stem cells. One of which is Diamond Blackfan Anemia

What is HLA compatibility and why is it important? (histocompatibility)

It is a genetic fingerprint on white blood cells and platelets. HLA (Human Leukocyte Antigens) are markers on the surface of white blood cells. HLA forms the basis for recognizing and rejecting foreign tissues. These HLA antigens give the body's immune system the ability to determine what belongs in the body and what does not belong. Whenever the immune system does not recognize the series of antigens on a cell that mark it as belonging in the body, it creates antibodies and other substances to destroy the cell. Objects that the body looks for and destroys are infection-causing bacteria, viruses, tumour cells and foreign objects such as splinters. In this way, the immune system defends the body against things that can enter the body and cause harm.

In order for a stem cell transplantation to be accepted by the immune system of the person receiving the cells they must either be his own cells (in which case there is a perfect histocompatibility match) or if they come from a sibling they must be compatible enough in order not to be rejected.

There are three Classes I types of human leukocyte antigens (genetic markers): HLA-A, HLA-B, HLA-C, and three Class II types: HLA-DR, HLA-DQ and HLA-DP that are important in transplantations. Since children inherit one haplotype from each parent, four different combinations are possible within a given family, so there is a one-in-four chance that each brother or sister will be a suitable match within the family.

There are over 20,000 histocompatibility types in the general population. Thus, the greatest chance of finding a matched stem cell donor exists within the patient's own family. The survival rate for a matched sibling with DBA is a considerable amount higher.