The hematopoietic stem cell (HSC) is an undifferentiated, pluripotent cell, which will give rise to all the fundamental cells of the blood: red blood cells, white blood cells and platelets.

It is a cell that retains the ability to proliferate and multiply.  In other terms it is capable to replicate itself and, simultaneously, generate new cells that, through processes of differentiation and development, will originate mature cellular elements.

Because they originate all the blood cells in the body and many other accessory or support cells.

Because they are essential to cure bone marrow insufficiency (e.g. aplasia) because they replenish the blood.

Because they are used to substitute bone marrow in case of leukemia, myeloma, thalassemia.

Because they can produce enzymes that are missing in certain genetic illnesses.

Bone marrow has got nothing to do with the spinal cord. Bone marrow used for transplants (hematopoietic marrow) has the appearance of normal blood and it is usually retrieved from the pelvic bones near the iliac crest. Bone marrow has the function of producing fresh blood cells (red blood cells, white blood cells and platelets) to substitute the ones that are normally removed from the blood stream. A red blood cell has an average life span of 120 days.

With the expression bone marrow hematopoietic stem cell transplant we intend a complex procedure used especially, but not only, in the treatment of leukimias and lymphomas. Stem cells can be obtained not only from bone marrow but also from peripheral blood after a specific preconditioning of the patient or from umbilical-cord blood.

For most people the word “transplant” evokes images of operating theatres and surgical instruments. In reality for the patient the procedure is carried out in two distinct phases:

-Pretransplant chemotherapy and/or radiotherapy, aimed at destroying all bone marrow cells of the patient, in first instance the malignant ones, of course

-Infusion of the bone marrow obtained from the donor.

The hematopoietic stem cells contained in the donated bone marrow are able to find their way by themselves arriving in the correct place where they can “start working”.

The stem cells can be obtained in two different ways. The choice depends on the indications given by the specialist and it reflects the patient’s and the donor’s characteristics.

The first and older way of obtaining HSC consists in bone marrow grafting from the posterior iliac crest and it requires hospitalization of the donor. The donor will be treated in the nearest qualifies centre where HSC are obtained after general or epidural anesthesia in about 45 minutes. The procedure has minimal risks which are connected with anesthesia and modality of grafting.

The quantity of bone marrow blood  obtained from the pelvic bones varies according to the size of the donor and the necessity of the patient but it is usually around 0,7 and 1 L. After the donation the donor is kept under scrutiny as a precaution for a few hours and then discharged with an indication to rest and take it easy for 4-5 days. The bone marrow subtracted from the donor regenerates itself in 7-10 days. The donor could manifest a slight pain in the area where the grafting has taken place, but it is self limited and vanishes in a few days. The donor will then be followed for a year post donation to keep his health condition under control.

In 1973, 16 HSC transplants (all from bone marrow) were performed in Europe, in 1983 they were 1.353, in 1997 7.7373 and in 1999 17.800, of which 5.733 allogeneic and 12.067 autologous. These data indicate the extraordinary success of HSC transplant and the great potential of this procedure.

Legislations vary in different countries. As a general rule, tough, it is necessary to be at least 18 years old (for legal reasons) and weighing at least 50kg. Obviously the donor has to be in good health and should not be affected by hematological diseases, severe chronic illnesses or other serious infective diseases (HIV-AIDS, Hepatitis viruses, ecc.) A complete screening for these conditions is performed at the moment of tipisation and before the possible donation.

Also in this case, legislation varies from country to country and the best way to gather precise information is to consult the website of your national bone marrow donor association (see the registries page). In general, the donor is examined by means of analysis of a blood sample or a saliva sample or a fragment of skin.

The results of the analysis will then be stored in a national electronic database, connected itself to other national databases to form a world-wide pool. It is within this database that possible compatible donors are found for patients awaiting transplant, are then called to undergo further and more detailed analysis to check the grade of compatibility.

Your commitment could save somebody’s life. Your refusal could otherwise condemn your genetic brother to death.