blood disorders
Special Blood Donation and Transfusion Procedures
Hematopoietic stem cell apheresis (stem cell transplantation)
In Stem Cell Transplantation , a donor gives only hematopoietic stem cells (undifferentiated cells that can develop into any type of blood cell) rather than whole blood. Before the donation procedure, the donor receives an injection of a special type of protein (growth factor) that stimulates the bone marrow to release stem cells into the bloodstream. Whole blood is drawn from the donor, and a machine that separates the blood into its components selectively removes the hematopoietic stem cells and returns the rest of the blood to the donor. Stem cell donors and recipients must have compatible leukocyte types (human leukocyte antigen, or HLA), a type of protein found on certain cells, rather than blood type. Hematopoietic stem cells are sometimes used to treat people with 