There are several methods available to collect donor stem cells. They can be taken, or "harvested," from peripheral blood, bone marrow, and umbilical cord blood. Donor sources can be the patient, a matched family member or an unrelated volunteer donor. The transplant team caring for your child will recommend one of the following stem cell collection methods.
Stem cells can be taken from the donor's bone marrow, the soft, sponge-like tissue in the center of most bones that produces all forms of blood cells: white blood cells, red blood cells and platelets. Stem cells are removed, usually from the hip bone, through a surgical procedure called a bone marrow harvest.
Stem cells, similar to those found in bone marrow, also circulate in the blood. Donors take a special medication to stimulate stem cell production over the five days before stem cells are collected. Stem cells are then removed by a special machine in a process similar to that of donating platelets while the blood is returned to the donor. These peripheral blood stem cells are stored and then later transfused into the patient to help the bone marrow recover and begin producing healthy blood cells.
Umbilical cord blood
Stem cells are present in the blood remaining in the umbilical cord and placenta of a newborn baby. These stem cells may be collected and frozen at the time of delivery. For children in particular, umbilical cord blood is becoming a more frequent source of donor stem cells.