bone marrow transplantation 骨髄移植
ライフサイエンス / ハイテクノロジー

A treatment for blood diseases such as leukemia, aplastic anemia, malignant lymphoma, and various immunodeficiency diseases, where bone marrow stem cells are taken from a donor and implanted into a recipient, allowing them to once again produce healthy blood. It was once also used to combat the decreased bone marrow function that can occur as a side effect of cancer treatment. The recipient's diseased hematopoietic stem cells, the cells responsible for creating new blood, are killed off with radiation and then substituted with the donor's healthy bone marrow. However, if the donor and recipient do not possess matching HLA types, a severe rejection reaction will occur following the transplant. There were previously numerous cases of a rejection reaction occurring even when HLA types matched, resulting in low success rates, but success rates have since risen considerably by giving the recipient substances such as biological proteins before the procedure, thereby reducing the occurrence of such reactions.

It was once necessary to remove approximately 1 liter of stem cells directly from the donor's femur, which resulted in the donor having to be hospitalized and placed under anesthesia, but it is now possible to extract stem cells from the bloodstream, or what is known as peripheral blood stem cell transplantation. Following extraction, the stem cells are then cultured in a laboratory. This type of transplant has also virtually eliminated the number of accidents during procedures.