Blood bone marrow in a process called hematopoiesis, which includes erythropoiesis, the production of red blood cells; and myelopoiesis, the production of white blood cells and platelets. During childhood, almost every human bone produces red blood cells; as adults, red blood cell production is limited to the larger bones: the bodies of the vertebrae, the breastbone (sternum), the ribcage, the pelvic bones, and the bones of the upper arms and legs. In addition, during childhood, the thymus gland, found in the mediastinum, is an important source of T lymphocytes. The proteinaceous component of blood (including clotting proteins) is produced predominantly by
Moore v. Regents of the University of California because of the potentially fatal amount of swelling in Moore's spleen. Moore signed a written consent form, authorizing the procedure. It said the hospital could "dispose of any severed tissue or member by cremation," and his spleen was removed by surgeons, who were not named as defendants, at UCLA Medical Center. Moore's blood profile returned to normal after only a few days, and further examination of his spleen led Golde to discover that Moore's blood cells were unique in that they produced a protein that stimulated the growth of white blood cells, which help to protect the body from infections.