The donor blood cells will be taken from the donor through a process known as apheresis. This will occur after the donor has received 2 days of granulocyte colony stimulating factor (G-CSF) to increase her/his white cell count. The G-CSF will also increase the number of very immature (stem cells) that are to be collected. Apheresis is similar to a platelet donation, but white cells and stem cells are collected instead. About 3 to 5 apheresis procedures will be needed to get enough cells for infusion. If apheresis is not used, donor bone marrow will be taken under general anesthesia.