WHAT ARE STEM CELLS?
Stem cells are “mother” cells from which all other blood cells (red blood cells, white blood cells and platelets) grow.
Bone marrow is the plant that produces the stem cells. It is a soft, gel-like tissue that fills the inside of bones like the pelvis. Bone marrow differs from the spinal cord. The latter is the part of the nervous system that descends into the spine.
Stem cells are found in:
- Bone marrow
- Peripheral blood circulation
- Umbilical cord blood
Stem cell transplant
Some diseases, such as leukemia, cause abnormal stem cell production or bone marrow dysfunction, and pose a danger to the patient’s life. In some cases, treatment is used to replace dysfunctional stem cells with those of a healthy donor through a stem cell transplant.
Stem cell transplantation is not the only therapeutic option for diseases such as leukemia and other cancers. First try treatments such as chemotherapy, radiation, and specialized drugs to try to stop the disease. However, in some cases, these treatments do not work, and the only way to save these patients is to replace their stem cells with other stem cells from a healthy person.
If a patient needs a stem cell transplant, who is the best donor?
The characteristics of the grafted stem cells should be as close as possible to those of the patient. Since these characteristics are hereditary, we first look for a compatible donor, that is, a person whose tissue genetic markers are sufficiently similar to those of the patient, in the family (usually among brothers or sisters). . The odds of finding a compatible donor in the family are about 25%, or one in four.
When no donor is found in the family, an attempt is made to identify a compatible unrelated donor using the so-called Stem Cell Donor Registry.
What are these tissue genetic markers that determine the compatibility between a donor and a recipient for stem cell transplantation?
These markers constitute the HLA system (Human Leukocyte Antigen). This system is different from the blood groups (A, B, O or AB). To determine the compatibility between a donor and a recipient, we proceed to HLA typing, that is to say to the analysis of the characteristics of antigens or proteins present on the surface of white blood cells. If the HLA system is not sufficiently similar between the donor and the recipient, the transplant can not be performed because it is a failure.
It is therefore important to have a registry of stem cell donors that is diverse and sufficient to make the transplant possible for the greatest number of people.