Bone marrow transplantation works to cure sickle cell disease by replacing unhealthy blood-forming cells with healthy cells. Red blood cells are produced in the bone marrow by immature blood stem cells. Bone marrow is a cavity in the bones where stem cells live and grow. Children with sickle cell disease have blood stem cells that produce abnormally shaped red cells called "sickle cells."
The transplant begins by giving the patient chemotherapy, which will get rid of the stem cells that produce the sickle cells. The patient then receives bone marrow from the donor, which contains healthy blood stem cells that do not sickle.
The bone marrow cells from the donor know where they belong in the body. They are given intravenously (by vein). They move through the bloodstream and settle in the bone marrow, where they will grow and produce new red blood cells, white blood cells, and platelets. This process is called "engraftment." Once the donor cells have engrafted, they produce healthy red blood cells. This prevents sickle cell-related complications from occurring in the future. It is acceptable to use a family donor if he or she carries the sickle cell trait (one copy of the sickle cell gene), since children with the trait have no sickle cell-related complications.