Bone Marrow Transplantation
Bone marrow transplantation is used for treatment of some cancers, notably leukemias. Found inside bones, the marrow contains stem cells that divide and develop into red blood cells and a variety of white blood cells including B cells, T cells, macrophages and platelets. Leukemias are cancers of developing cells within the marrow. To treat leukemias, the patient's marrow cells are destroyed by chemotherapy or radiation treatment. Bone marrow from a donor that has matching or nearly matching HLA antigens on the cell surface is then introduced into the patient. Bone marrow transplantation is also used to replace marrow in patients who required very high doses of radiation or chemotherapy to kill the tumor cells.
Transplants are classified based on donor source.
Allogeneic transplantsThe marrow donor is often not genetically related but has matches with at least five out of six cell surface antigens that are the major proteins recognized by the immune system (HLA antigens).
Autologous transplantation
Patients receive their own marrow back after chemotherapy or radiation treatment. This type of bone marrow transplant is used for non-marrow related cancers for which conventional treatment doses have been incompletely effective.
