Bone marrow is the spongy tissue inside some of the bones in the body, including the hip and thigh bones. Bone marrow contains immature cells, called stem cells. Many people with blood cancers, such as leukemia and lymphoma, sickle cell anemia, and other life-threatening diseases, rely on bone marrow or cord blood transplants to survive. Healthy bone marrow and blood cells are needed in order to live. When the disease affects bone marrow so that it can no longer function effectively, a marrow or cord blood transplant could be the best treatment option; for some patients, it is the only potential cure. Bone Marrow Transplantation (BMT) is a useful strategy for the treatment of leukemia, severe combined immune deficiency, enzyme deficiencies, autoimmune disease, and osteoporosis. Furthermore, BMT plays an important role in the induction of immune tolerance in organ transplantation. Bone marrow is a spongy tissue, and is made up of Hematopietic Stem Cells (HSCs), Mesenchymal Stem Cells (MSCs), and various blood cells. HSCs differentiate into common myeloid- and lymphoid-precursor cells and then terminally differentiate into erythrocytes, monocytes, platelets, neutrophils, dendritic cells and other cells.