A cord blood bank is a facility which stores umbilical cord blood for future use. Both private and public cord blood banks have developed since the mid- to late-1990s in response to the potential for cord blood transplants in treating diseases of the blood and immune systems.
Public banks accept donations to be used for anyone in need. Unlike private cord blood banking, public cord blood banking is supported by the medical community. However, there are very strict regulations which public banks need to follow in order to enable the donated units to be added to a registry. Generally, an expectant mother interested in donation should contact the bank before the 34th week of pregnancy. The National Marrow Donor Program has a list of public cord blood banks on their website. Once the blood is donated, it loses all identifying information after a short period of initial testing. Families are not able to retrieve their own blood after it has been donated, but, as discussed below, it is very unlikely that they would be able to use the sample themselves.
Private banks store cord blood with a link to the identity of the donor, so that the family may retrieve it later if it is needed. The parents have custody of the cord blood until the child is an adult. The cord blood might someday be needed by the donor baby, or it could be used by a relative who is a close enough match to receive a transplant from the donor (typically a sibling). Private banks charge a fee of around $1000–$2000 to preserve the harvested cord blood for family biological insurance. Private banks have been criticized for aggressive marketing campaigns to expectant parents.
In the United States, the Food and Drug Administration regulates cord blood under the category of “Human Cells, Tissues, and Cellular and Tissue Based-Products.” The Code of Federal Regulations under which the FDA regulates public and private cord blood banks is Title 21 Section 1271. Both public and private cord blood banks are eligible for voluntary accreditation with either the American Association of Blood Banks AABB or the Foundation for the Accreditation of Cellular Therapy FACT. Potential clients can check the current accreditation status of banks from the AABB list of accredited cord blood banks or the FACT search engine of accredited cord blood banks. Other countries also have regulations pertaining to cord blood.
Cord blood contains hematopoietic stem cells, progenitor cells which can form red blood cells, white blood cells and platelets. Cord blood cells are currently used to treat blood and immune system related genetic diseases, cancers, and blood disorders. Medical critics of routine cord blood collection emphasize that, if neonatal cord blood is so physiologically valuable, it is of great benefit for the neonate to receive upon birth.
Benefits of banking cord blood
Cord blood stem cells are currently used in the treatment of several life-threatening diseases, and play an important role in the treatment of blood and immune system related genetic diseases, cancers, and blood disorders.[4]
The first clinically documented use of cord blood stem cells was in the successful treatment of a six-year-old boy afflicted by Fanconi anemia in 1988. Since then, cord blood has become increasingly recognized as a source of stem cells that can be used in stem cell therapy.
Recent studies have shown that cord blood has unique advantages over traditional bone marrow transplantation, particularly in children, and can be life-saving in rare cases where a suitable bone-marrow donor cannot be found. Approximately 50% of patients requiring a bone marrow transplant will not find a suitable donor within a critical period. In certain instances, there may be some medical issues around using one's own cord blood cells, as well as availability of cells, which will require treatments done using cells from another donor, with the vast majority being unrelated donors. However, studies have shown that cord blood stem cells can also be used for siblings and other members of your family who have a matching tissue type. Siblings have up to a 75% chance of compatibility, and the cord blood may even be a match for parents (50%) and grandparents.
Banking methods
The FDA governs the collection, processing, storage, labeling, packaging, and distribution of cord blood stem cells. There are two different standards which can apply: cGTP (current Good Tissue Practices) and cGMP (current Good Manufacturing Practices). cGTP standards apply to the collection, processing and storage of human cells, tissues, and cellular/tissue-based products (HCT/Ps) and are regulated by the Center for Biologics Evaluation and Research. All US cord blood banks must be compliant with cGTP standards. cGMP standards apply to the manufacture of a product that is considered a drug. How one determines whether a bank must be compliant with cGMP standards is based upon the product that they manufacture. If a cord blood bank manufactures cord blood stem cells that are overly manipulated or the cells are used in a different basic biologic function, that product is regulated as a drug, and both cGTP and cGMP standards would apply. If a cord blood bank manufactures cord blood stem cells that are minimally manipulated and the cells are used for the same basic biologic function and/or for use in people that are 1st or 2nd degree blood relatives, that product is regulated solely under cGTPs.
cGTP standards are based upon cGMP standards, and thus there are many similarities.
Safety and effectiveness of using one's own cells unclear
Using one's own cord blood cells might not be wise or effective, especially in cases of childhood cancers and leukemia. Children who develop an immunological disorder often are unable to use their own cord blood for transplant because the blood also contains the same genetic defect. Nearly all of the transplants using privately banked cord blood have gone to relatives with pre-existing conditions, not to the donors.
Additional issues include the possible contamination of the cord blood unit with the same cancer diagnosed later in life; for example, abnormal cells have been detected in filters containing newborn blood of children who were not diagnosed with acute leukemia until the age of 2 to 6 years. The high relapse rates after autologous or syngeneic tranplant and the benefit of a graft-vs.-leukemia effect of an allogeneic transplant suggest that autologous cord blood would not be the ideal source of stem cells for patients with leukemia needing a transplant
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