Allogenic transplant: A transplant of stem cells that come from a person other than the patient.
Apheresis: The process of drawing blood from a donor, circulating it through a machine to separate and isolate the stem cells, and returning the rest of the blood and plasma to the donor.
Autologous transplant: A transplant in which the patient's own stem cells are used.
Bone marrow: A spongy tissue inside large bones where red cells, white cells and platelets are made.
Engraftment: The stage after transplant when the stem cells start to grow and make blood cells.
Graft-versus-Host Disease (GVHD): A condition when the donor immune system attacks the patient's body. GVHD ranges from mild to serious. It has acute and chronic forms.
Human Leukocyte Antigens (HLA): Proteins on white blood cells that make each person's tissue unique and define the transplant tissue type.
Stem cells: Cells that can grow into red blood cell, white blood cells or platelets.
Syngeneic transplant: A transplant from one identical twin to the other.