Preparation
First, the recipient and donor of the bone marrow must be prepared for the procedure. A thorough evaluation, physical exam and medical history must be performed on each, and tests must be performed to ensure that blood and tissue match between the two. Human leukocyte antigen (HLA) tissue is compared to be sure that the antigens match. The more similar those tissues, says the University of Virginia Health System, the better the chances that the donated stem cells settle into the marrow of the recipient and create new blood cells.
Collection of Bone Marrow
Next, the bone marrow is collected from the donor. A needle is inserted into the bone--typically a hip bone or shoulder bone--and the marrow (the soft part inside the bone) is withdrawn. The stem cells inside the bone marrow are then separated for transplantation to the donor.
The Transplant
A catheter is placed in a vein, and the bone marrow is then transplanted intravenously. It's not a surgical procedure, says UVA, but more like a blood transfusion. The stem cells from the bone marrow then travel to the bone marrow of the recipient, replicate and create more healthy blood cells.
Other Steps
Prior to some bone marrow transplants, the recipient must undergo chemotherapy or radiation therapy to destroy cancer cells and create space for the production of healthy new blood cells to take their place, says UVA. Stem cells can also be transplanted via blood, rather than bone marrow. Blood is withdrawn into a machine, which separates the stem cells, then circulates the leftover plasma and blood back into the body.
