Peripheral Blood Stem Cell Transplant (cont.)

How are the stem cells removed from the blood?

The blood is filtered through a machine and the stem cells are skimmed off. The removal of the cells is termed pheresis or apheresis (from the Greek "aphairesis" for removal). The stem cells then may be used right away for bone marrow transplant or stored in liquid nitrogen until needed.

How is the patient "prepared" for the transplantation?

Before the transplant is done, the patient receives high-dose chemotherapy and/or radiation therapy to destroy diseased cells (the leukemic cells, lymphoma cells, solid tumor cells, the diseased immune system cells in scleroderma, etc.) The stem cells are then returned to the patient, where they can produce new blood and immune cells and replace the cells destroyed by the treatment.

How is the transplantation actually done?

The stem-cell preparation is infused into a vein and, once there in the blood stream, the stem cells act like homing pigeons and head straight for the bone marrow space.
Last Editorial Review: 4/15/2002

Source: MedicineNet.com
http://www.medicinenet.com/peripheral_blood_stem_cell_transplant/article.htm