July is National Cord Blood Awareness Month, a campaign that encourages expectant parents around the world to learn more about cord blood stem cells and cord blood banking. This practice involves taking blood from the umbilical cord or placenta after the birth of a newborn and processing, testing, freezing, and storing it as a source of stem cells that may be used for a transplant.
Despite the growing acceptance of cord blood banking, many people still do not have a clear understanding of the different ways this blood may be stored and the potential — and limitations — of its use to treat disease.
Memorial Sloan Kettering pediatric hematologist Andromachi Scaradavou has extensive experience in the clinical use of cord blood transplants. She is also Medical Director of the National Cord Blood Program and has spoken nationally about cord blood collection and banking and its use in transplantation.
A Rich Source of Stem Cells
Dr. Scaradavou explains that cord blood is a rich source of hematopoietic, or blood-forming, stem cells, which are also found in the bone marrow of adults and in the peripheral (circulating) blood after certain treatments. Currently, cord blood cells are useful for transplantation into another person to treat the same diseases that are treated by stem cell transplants from adult donors, including leukemias, lymphomas, and other blood cancers, as well as immune deficiencies and metabolic diseases.
Cord blood cells offer some advantages over bone marrow or blood stem cells from adult donors. “Because cord blood contains immune cells that are less mature, there is a lower chance of graft-versus-host disease, a serious complication of donor-derived transplants,” Dr. Scaradavou says. “As a result, the donor’s cells don’t have to match perfectly with those of the patient. Cord blood also poses less risk of infection from viruses.”
“In addition, there are large numbers of cord blood donors from all ethnic backgrounds to meet the needs of a diverse population of patients who require stem cell transplants,” she adds.
There are two types of cord blood banks — public and private. Public banks store cord blood for use in any patient who needs a stem cell transplant, although the cord blood is typically considered a donation and is not reserved for the donor or the donor’s family. The US Food and Drug Administration, which oversees public cord blood banking, requires these banks to comply with stringent safety requirements to ensure the blood is safe for transplantation.
Private banks, which have surged in number in recent years, allow cord blood to be stored for use later by the donor (called an autologous transplant) or by a family member who either is already affected by or later develops a disease treatable with a transplant. Private banks charge fees for cord blood collection and storage, or for the release of a stored cord blood unit (and sometimes for both). An increasing number of parents are storing cord blood in private banks in the belief that the stem cells may prove useful if their child develops a disease.
Recommendations for Cord Blood Banking
Those experts who have made recommendations, including the American Academy of Pediatrics (AAP) and the American Society for Blood and Marrow Transplantation (ASBMT), strongly support public over private cord blood banking. The AAP recommendations state that “private storage of cord blood as ‘biological insurance’ should be discouraged since there are no data to support it at the current time.” The ASBMT states that “the chance of using one’s own cord blood is very low — currently less than 4/100th of one percent [1 in 2,500].”
One reason chances are so slim that an autologous cord blood transplant may be effective is that patients nearly always need cells from a healthy donor — not their own cord blood cells — to cure their disease.
“What many people may not realize is that most disease conditions that might be helped by cord blood stem cells are already present in the infant’s cord blood,” Dr. Scaradavou says. “Even with a currently treatable disease such as childhood leukemia, a person’s own cord blood cells would not help the disorder because they contain the molecular abnormality that gave rise to the disease.”
In addition, cord blood cells are often discussed as a treatment for genetic diseases, but because the cells carry the same genetic defect, they would need to be manipulated through some type of gene therapy — a technology still in its early stages.
Some researchers are using cord blood in clinical research, investigating its potential in the development of therapies for diseases not traditionally treated with stem cell transplant — including brain injuries, cerebral palsy, and diabetes — and to regenerate tissue. Although other therapeutic applications for cord blood may eventually emerge through this research, experts say it is impossible to tell how far off such treatments are, or whether they will be effective.
There are specific situations in which private cord blood banking is advised. For example, the AAP supports “directed donations” if a newborn child has an older sibling with a medical condition who could potentially benefit from cord blood transplantation.
A Personal Decision
Dr. Scaradavou emphasizes that any decision about banking cord blood is a personal choice because each situation is unique and affected by a wide range of factors. “There is no general recommendation I can make about whether parents should bank their child’s cord blood,” she says. “The decision should be made only after we consider the specific information and wishes of the parents.”
Dr. Scaradavou encourages expectant parents considering cord blood collection to learn as much as possible and consult with their physicians before deciding whether, and how, to bank cord blood. “I don’t recommend delaying the decision until the birth is impending. Not every hospital is set up to collect cord blood so other arrangements may need to be made.” she says. “We want parents to have a clear understanding of what each option entails and have a plan in place well in advance.”
Resources with information about cord blood collection and donation: