Cord Blood
after birth, usually the umbilical cord is discarded with the placenta. However, researchers have found that recovered from umbilical cord blood is a rich source of primary cells. The primordial cells are unspecialized cells that produce all other blood cells, including clotting platelets and red blood cells and white. Like donated bone marrow, umbilical cord blood can be used to treat various genetic disorders affecting the blood and immune system, leukemia and certain cancers, and some inherited biochemical disorders. To date, more than 45 disorders that can be treated with stem cell from umbilical cord blood.
Currently, there are commercial companies that offer parents a storage of cord blood for your baby. Prospective parents who are considering this option should gather as much information as possible to make an informed decision.
What are the primordial cells and why are they valuable?
primordial cells of the blood, which in most cases are found deep in the bone marrow, are the fabric of the blood system. Permanently make new copies of themselves and produce cells that make most other types of blood cells. The primordial cells are critical to the success of bone marrow transplantation (BMT or, as they are known by its acronym in English), and that continue to produce blood cells indefinitely.
marrow transplants marrow can save the lives of people suffering from leukemia (cancer of white blood cells) and other cancers, or people with serious blood disorders like aplastic anemia, in which the body does not produce enough blood cells. The primordial cells can help improve the capacity of a person's blood and immune system when affected by an inherited defect (genetic) or have suffered severe damage or were deliberately destroyed by cancer treatments. Currently, the donated bone marrow is the most common source of primary cells.
What are the advantages of cells primordial umbilical cord blood?
Studies suggest that the primordial cells from umbilical cord blood offer some important advantages over those taken from bone marrow. On the one hand, the primordial cells from umbilical cord blood are much more readily available and can be taken immediately from the placenta at the time of delivery. Harvesting stem cell from bone marrow requires a surgical procedure, usually under general anesthesia, which can cause post-operative pain and a small risk to the donor.
is broader range of recipients who may benefit from umbilical cord stem cell. These can be stored and re-transplanted into the donor, a family member or a receiver without kinship. For a bone marrow transplant is successful, there must be an almost perfect match of certain tissue proteins between donor and recipient. When using primary cells from umbilical cord blood, the donor cells appear more likely to "take" or engraft, even when there is complete correspondence between the tissues.
A potentially fatal complication called graft versus host disease (GVHD, in English), in which donor cells can attack the recipient's tissues, appears to occur less frequently with cord blood than bone marrow. This may be because cord blood has a mute and certain immune system cells, usually active in an immune reaction, have not yet educated to attack the recipient. A study in 2000 found that children who received a transplant of umbilical cord blood of a sibling with a high degree of correspondence were 59 percent less likely to develop GVHD than children who received a bone marrow transplant from same way.
The use of cord blood can cause umbilical stem cell transplants available more quickly for people who need them. Each year, approximately 30,000 people diagnosed with conditions that can be treated with bone marrow transplantation. Approximately 25 percent of these people have a relative whose tissue is compatible. While for many people can locate suitable donors through national bone marrow registries, the process can take months. Donors are located within four months to about 50 percent of patients. It is often difficult to find a person with compatible bone marrow for members of ethnic groups and nonwhite race. Transplants of umbilical cord blood enable a greater number of people belonging to these groups access to treatment more quickly. The primordial cells of umbilical cord blood stored in banks may be more readily available, which sometimes is of particular importance for patients with severe cases of leukemia, anemia or immune deficiency that otherwise would die before they can find someone compatible.
umbilical cord blood is also less likely to contain certain infectious agents such as viruses, which can pose a risk to transplant recipients. Also, some studies suggest that cord blood may have a greater capacity than the bone marrow to generate new blood cells. In every ounce of umbilical cord blood, there is an almost ten times more blood-forming cells. This suggests that it requires a smaller amount of primordial cells from umbilical cord blood for a transplant to be successful.
addition, the primordial cells from umbilical cord blood offer some interesting possibilities of gene therapy for genetic diseases, especially those related to the immune system. Dr. Donald Kohn, and colleagues from Children's Hospital of the University Southern California in Los Angeles and the University of California, San Francisco, made the first attempt at gene therapy with cord blood in 1993 in three children suffering from adenosine deaminase deficiency (ADA), a potentially fatal flaw that cripples the system immune. Children, who also received special treatment with drugs, appear to be healthy to date, although his blood now carries only a small amount of the introduced gene in primary cells.
Where and when to collect and store samples of umbilical cord blood?
Parents who are expecting a baby can make arrangements before birth to take blood from the umbilical cord immediately after birth (within 15 minutes of delivery) and to store it for their own use in a commercial blood bank. They can also donate to a public bank to make it available to anyone who needs a transplant and which is compatible. If parents use a commercial bank, the initial costs range from $ 250 to $ 1,500, plus an annual storage fee of $ 50 to $ 100. Some insurance companies are beginning to cover these costs.
While public banks pay the processing of samples of umbilical cord blood, require los padres completen un extenso cuestionario sobre su salud y las enfermedades que han tenido. Las pruebas requeridas, para enfermedades como la hepatitis y el VIH, pueden ser costosas para los padres. Además, los arreglos con estos bancos deben realizarse al menos 90 días antes de la fecha del parto.
¿Quiénes deberían considerar almacenar la sangre del cordón umbilical?
A los padres que esperan un bebé y que tienen antecedentes familiares de enfermedades genéticas, como anemias severas, trastornos inmunitarios o algunos tipos de cáncer, les conviene considerar el beneficio que representa para la familia almacenar sangre del cordón umbilical. La mayoría de las familias no tiene estos factores de risk and only have one chance in 20,000 of needing a stem cell transplant. Families can request detailed information and advice to doctors and geneticists.
Families wishing to donate umbilical cord blood of their baby to a public bank for use by others should be fully informed of their responsibilities and the consequences of this donation.
What are some of the issues regarding them?
not yet been established universal standards for the collection and storage of cord blood, but they are required to exchange samples between different banks. Currently, some banks collect whole blood samples, while others separate the red cells, white cells and other blood components before freezing. There are also other security issues concerning the method of collecting cord blood in order to avoid contamination. The Ministry of Food and Drug Administration (FDA) is considering these issues.
There are still many unresolved ethical issues concerning the storage of umbilical cord blood banks. Some of them are: who owns the blood sample? How is informed consent of parents before collecting the blood? How is provided with the necessary advice to help parents make an informed decision? How should you handle the obligation to notify parents and child donors of the results of medical tests for infectious diseases and genetic information? How can you maintain the privacy and confidentiality? How services will be provided for the collection and access to cord blood fairly? Does
transplant umbilical cord blood is still experimental?
The use of primary cells from cord blood for transplantation holds great promise but this area of \u200b\u200bmedical science is still largely experimental. Until 1988, French researchers conducted the first successful transplant with stem cell umbilical cord blood. The transplant was taken from a newborn to a sibling of five years with a syndrome that included severe anemia, skeletal defects (Fanconi anemia). Since then, the umbilical cord blood from donors with blood relation or not, has been transplanted successfully in approximately 2,000 people worldwide. Doctors at the Mattel Children's Hospital of the University of California, Los Angeles, recently reported that three Young treated for life-threatening immunodeficiency syndrome (X-linked lymphoproliferative and immunodeficiency with hyper IgM) had normal immune systems two years after receiving umbilical cord stem cell donors without a family relationship.
In 1998, the largest study ever conducted transplant umbilical cord blood donor no relation suggested that there was a feasible procedure for patients (adults and children) who did not have a donor with compatible kinship. Survival rates for patients receiving umbilical cord blood or bone marrow no relation donors were similar.
However, until you get the results of additional large studies, insurance companies and Medicaid still reluctant to cover the cost of storage. Consequently, the service in most cases is only accessible to those families who can afford it. It is highly unlikely that a child needs a stem cell transplant or, if you ever need that umbilical cord blood of the child itself is the ideal source of primary cells. There is no proven even if a transplant using primary cells of the same child is effective or even safe, especially in the case of cancer children. For these reasons, the American Academy of Pediatrics (AAP) does not consider it prudent to store umbilical cord blood as a biological protection in the case of families with no history of the disorders mentioned above. However, the AAP and some other scientists are in favor of collecting and storing umbilical cord blood in public banks that can be used by recipients without family ties in urgent need of cell transplantation. This could be particularly useful for ethnic and racial groups are underrepresented in the registries of volunteer bone marrow. March of Dimes
is optimistic about the possibilities of treatment with umbilical cord blood and is evaluating the results of the investigations so far seem promising. However, parents are expecting a baby should be well informed to make your choice based on appropriate advice to medical reasons.
Source: March of Dimes
References American Academy of Pediatrics Work Group on Cord Blood Banking. Potential Cord blood banking for future transplantation: subject review. Pediatrics, Volume 104, Number 11, July 1999, pages 116-118.
Rocha, V., et al. Graft-versus-host disease in Children Who Have Received a cord-blood or bone marrow transplant from an HLA-identical sibling. New England Journal of Medicine, Volume 342, Number 26, June 22, 2000, pages 1846-1854.
Rubenstein, P., et al. Outcomes Among 562 recipients of placental-Blood Transplants from Unrelated Donors. New England Journal of Medicine, 1998, volume 339, pages 1565-1576.
Ziegner, U., et al. Unrelated umbilical cord stem transplantation for X-linked immunodeficiencies. Journal of Pediatrics, Volume 134, Number 4, April 2001, pages 70-573. 09-1018-98 11/02
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