A cord blood program collects blood left in the umbilical cord and placenta after childbirth. It then processes and stores the blood, which is used to treat people who need blood-forming stem cells replaced. Blood-forming stem cells, called hematopoietic stem cells (HSCs), are normally harvested from adults, who produce them in their bone marrow. Cord blood banking increases the potential donor pool.
Blood cells and immune cells must be constantly replenished by the body, and HSCs are the mechanism that makes that possible. These cells, found in bone marrow, continually reproduce themselves and differentiate into replacement blood and immune cells of all types. HSCs are given to patients who have had their own hematopoietic system destroyed by radiation or chemotherapy. This procedure is known as a cord blood transplant.
Technicians collect blood from the placenta and the umbilical cord. They do so after the birth process is complete, and donating does not change the birth itself at all. The blood, and a sample of the mother’s blood, are tested for certain diseases. Processing then extracts and discards the plasma and, usually, the red blood cells, leaving the portion that holds the HSCs. This portion, sealed in a plastic bag, is stored at very low temperature in a nitrogen freezer.
A critical function of each cord blood program is human leukocyte antigen (HLA) typing. HLA is an important component in the immune system. There must be a certain minimal match between the HLA configuration of a donor and that of the recipient to ensure the best possible outcome of each transplant attempt. Cord blood donations are tested at collection, and again before each cord blood transplant, to minimize the risk of a mismatch.
Each cord blood program typically maintains a searchable database of the units of cord blood it has available. The database lists each unit by HLA type. Programs also send listings to Bone Marrow Donors Worldwide, an international bone marrow and cord blood registry with headquarters in the Netherlands. Medical facilities and professionals can request detailed information about units that might be suitable for transplant to their patients.
Every cord blood program operates through a regional network of cooperating birthing hospitals. The program will interview prospective donors before the birth, gathering medical histories of both parents and completing preliminary paperwork. Donors must not have a family history of certain blood disorders and must not have been exposed to a list of diseases that involve blood-borne infection.