INTRODUCTION-
In mammalian species, the umbilical cord carries nutrient rich blood and gases to the fetus through the arteries and veins it encloses. After delivery, a major portion of the umbilical cord is discarded, and the smaller portion left attached to the infant is allowed to dry off. Research in recent times indicates that the blood contained in the umbilical cord or Umbilical Cord Blood is rich in “Stem Cells”.
- Stem cells are a part of the “haematopoietic system”; or the system that is responsible for the production of various mature blood cells present in the body. The production of the blood cells from immature to mature stages takes place in the red bone marrow.
- The different mature blood cells need constant replacement that is provided by the stem cell.
- Some stem cells are differentiated; that is, they are slated to produce a specific type of blood cell. Still another stem cell type is the pluripotent stem cell. Researchers have only recently found sources of it in the bone marrow, placenta and umbilical cord. These pluripotent cells acquire, through a process of differentiation under specific conditions, let us say, an identity; be it a white blood cell, red blood cell, platelet etc.
There are few active sites of blood cell production in the adult body. These are responsible for producing the blood cells through out an individual’s life span. Blood diseases can either incapacitate these centers or create imbalances in the blood cell count. Traditionally, blood diseases have been treated with chemotherapy, marrow transplants or transfusions.
Scientists are now able to manipulate the haematopoietic stem cells found in Umbilical Cord Blood externally to form a specific type of cell. Once transplanted, the stem cells have helped to treat diseases like leukemia, lymphoma and inherited diseases like sickle cell anemia.
Pluripotent cells have been manipulated externally to grow into organs and even nerve cells, where they can be used to treat conditions like Parkinsons. Although these cells are found in the placenta and Cord Blood, the richest source of these stem cells is from discarded embryos themselves. This has resulted in much controversy.
UMBILICAL CORD BLOOD BANKS-
Researchers now urge parents to store or donate the Umbilical Cord Blood to specialized “Cord Blood Banks”. These can be either public or private institutions.
- Private Cord Blood Banks
This system is run by individuals or private organizations. The organization will store the Cord Blood irrespective of medical reasons. There are charges for collection and storage. The arguments against private cord blood banking are –
- If the child has inherited blood disease, the Cord Blood would be affected too. It would be useless to have it stored in that case.
- Doctors also prefer, in cases of children with leukemia, to have the Cord Blood of a healthy donor.
- Private banking does not allow for choosing from an array of donors. It can only hold an individual’s Cord Blood for their personal or immediate family’s needs.
The advantage of this system is that blood from a healthy child with no inherited diseases can be maintained as insurance, in case a family member or the child itself should need it in the future.
- Public Cord Blood Banks
This system is usually government run. There are generally no charges for collection and storage. Parents are encouraged to donate Cord Blood to Public Banks.
The reasons are -
- The chances of needing the Cord Blood are rare for a child in a family without history of disease.
- By donating the Cord Blood, parents contribute to an already growing reserve. This way, another person from anywhere in the world may find a match in the donated blood.
- Often, a person may not find a match among relatives for a marrow transplant. With a stem cell transplant being a viable option, a Public Cord Blood Bank would ensure a chance for the most appropriate cord blood unit even from several unrelated donors.
The disadvantage of this system is that it is not always guaranteed that the donor will receive Cord Blood should he or she need it. It may have been donated. However, matches may be found from among many other donated samples.
The match referred to is required between the donor’s and recipient’s HLA antigens. The closer the match is, the better is the body’s chance of accepting the new stem cell.
The first ever Cord Blood Bank in the world was started in New York’s Milstein National Cord Blood Center. It is a Public Cord Blood Bank.
Today, there are over 40 Cord Blood Banks worldwide, both public and private.
CORD BLOOD COLLECTION AND STORAGE-
The Cord Blood Bank that the parents have chosen is generally responsible for collection of the blood.
There are usually lists of participating hospitals in every country. However, the related authorities (delivery doctors, nurses) must be aware of the mothers’ wish to donate or store Cord Blood after the birth.
Normal procedure includes
- Asking the mother and father for their health related history
- Blood tests to rule out HIV infections, other blood diseases
- Signing of a consent form.
The blood is collected either in-utero or immediately after the birth. The Cord Blood is taken to the Cord Blood Bank. Some tests are performed; this ensures the blood is suitable for storage. The results from the donor’s doctor regarding physical findings and blood tests are all considered.
The blood is then ready for storage at around minus 180 degrees centigrade.
It is not certain for how long Cord Blood can be stored. Current literature states that it can be safely stored for at least 10 years.
