Mobilized peripheral blood stem cells (PBSC)
PBSC isolation is a nonsurgical procedure, called apheresis. Before PBSC donation, donors are given injections of a drug such as tevagrastim (G-CSF) which mobilizes stem cells from bone marrow into the peripheral bloodstream. During this apheresis procedure, blood is drawn from one arm and passes through a machine that collects the stem cells. The remaining portion of the blood is then returned to the donor via a catheter inserted in the other arm. Seventy-five percent of all PBSC donations are completed in one apheresis session, but sometimes several apheresis sessions may be needed to collect a sufficient number of stem cells from a donor. After donation, collected blood stem cells are transported for transplant. Advantages of PBSC versus bone marrow transplantation is that it is less risky cell collection approach, donor available for subsequent PBSC collections, there is larger number of donors available and larger number of CD34 positive stem cells is obtained. Among patients older than 20 years, peripheral blood is the most common source of allogeneic grafts.