Saturday, 23 July 2011

An Alternative to Bone Marrow Transplant

Published in "Panorama"

An alternative for bone marrow transplant

Provide a security blanket for your baby and family members by banking your baby’s umbilical cord blood stem cells. This is despite the probability of usage by the family being anywhere between 1 in 200 to 1 in 20000. Save a byproduct of the birth process and potentially save a life.

The umbilical cord stem cell bank could be just the solution to a host of diseases including various genetic disorders that affect the blood and the immune system, leukaemia and certain cancers as well as some inherited disorders of body chemistry.

Blood from the umbilical cord which is usually discarded as waste, along with the placenta, is retrieved, tested, processed and stored since it is a rich source of stem cells. The cells, cryopreserved at minus 196 degrees can be thawed and used for treatment, several tens of years later.

The potential for the future is immense. Umbilical cord cells can be used tens of years after a person is born to treat ailments that may develop due to genetic predispositions. Parents who have a history of certain genetic diseases such as severe anaemia should consider opting for this facility. The highlight of cord blood stem cells is that they benefit a wide range of recipients including the donor, his siblings, other family members and even unrelated recipients. Even if there is a slight mismatch of tissues, these cells are more likely to 'take', by contrast to bone marrow cells which need perfect matching.

Yes, this concept of biological insurance is slowly gaining ground in India as in other Western countries, with the recent establishment of India's private cord blood stem cell bank, 'Lifecell' launched in October last year in Chennai. Asia Cryo Cell Private Limited (ACCPL) is in technical collaboration with Florida based Cryo Cell International (CCI), an organization accredited by the American Association of Blood Banks and registered with the FDA. Pioneers in umbilical cord banking with a track record of over twelve years, CCI has the largest repository of banked samples, reveals Dr. Saranya Nandakumar, Medical Director of ‘Lifecell’.

Blood stem cells, found mostly in bone marrow, are the factory of the blood system since they continually reproduce themselves and produce cells that make every other type of blood cell. These include the Oxygen carrying Red blood corpuscles (RBC), Infection-fighting White blood corpuscles (WBC) and clot-promoting platelets. Stem cells are the master cells, which are responsible for producing all the mature cells in our blood and immune system. Hence, stem cells are also the key to successful bone marrow transplantation involved in saving lives.

Until recently, bone marrow was seen as the most common source of stem cells. However, studies done during the 1970s revealed that human umbilical cord blood contain the same kind of stem cells found in bone marrow, but can be transplanted with less risks and require less than perfect match as compared to bone marrow. For the first time in 1988 in France, doctors successfully transplanted cord blood into a five-year-old boy suffering from Fanconi’s anaemia. Subsequently over 3500 successful cord blood transplants have been done for the treatment of various diseases.

Umbilical cord blood is even seen as effective transplant therapy, especially in treating diseases such as leukemia, sickle cell anaemia, aplastic anaemic, various other forms of anaemia, lymphoma, neuroblastoma, retinoblastoma and several malignant and non-malignant disoders. The non-malignant diseases are primarily inherited disorders of the blood and immune systems, or diseases affecting metabolism. More recent research has identified a role for stem cells in the treatment of Parkinson’s disease, Stroke, multiple sclerosis, osteoarthritis, spinal cord injuries, cardiac disease and lupus and possibly Diabetes Type Ia and II and Alzheimer’s disease too.

Harvesting stem cells from cord blood has certain advantages over stem cells from marrow. One of the greatest advantages of cord blood stem cell transplants is that they are available more quickly for people requiring such transplants, than bone marrow. Harvesting stem cells from bone marrow requires a surgical procedure done under anesthesia and is a tedious process that causes some discomfort. In contrast, collecting stem cells from cord blood is neither risky nor painful and can be achieved within five minutes, soon after the birth of a child. Also, a broader range of recipients may benefit from cord blood stem cells since it does not require to be perfectly matched with the recipient’s tissue proteins (Human Leukocyte Antigens - HLA) as required in bone marrow transplants. Cord blood stem cells are likely to engraft even when there are partial tissue mismatches.

The risk of a serious complication – graft versus host disease (GVHD) is much less with cord blood stem cells than with bone marrow transplant. GVHD is a condition where the donor cells attack the recipient’s tissues and the condition could be fatal. Cord blood is also less likely to contain certain infectious organisms like viruses which can in themselves pose a threat to transplant recipients, explains Dr.Saranya.

On the flip side, the amount of cells available from the cord blood may not be sufficient to transplant in an adult patient. The two major factors determining the success of cord cell transplant are the weight of the adult and the quantity of stem cells transplants. The target age group for cord blood transplant per se are the pediatric age group, with a body weight not exceeding 65 kg. Secondly, because this quantity is smaller, these cells once they are introduced into the recipient, have to find their way to the target organ which could be the bone marrow, brain, spinal cord, pancreas, et al. They have to find their way here, settle down there and then start multiplying. This is the whole idea in doing a stem cell transplant. This period of settling down and multiplication, termed homing and engraftment may be longer with cord blood stem cells and it therefore exposes the patient to greater risk of infection. However recent studies suggest that stem cells from the cord blood have a greater ability to generate new blood cells in comparison to those from the bone marrow, thus reducing the need for a larger number of cord blood cells to enable successful transplant, explains Dr.Saranya.

A disadvantage of using cord blood may arise when treating a genetic disorder, as the stem cells in the cord blood would also carry the marker for the same defective gene.

What are the conditions under which cord blood would not be considered at all for collection and preservation? Dr.Saranya explains, "We have to go into a detailed maternal history when a person registers with us. If the mother herself has some serious illness for which she is on continuous medication, then we would not take the cord blood from her child. Secondly, the pregnancy itself should be normal and not fraught with problems as there might be complications either later on during pregnancy or at the time of delivery. In these situations, it is better not to confuse the issue by going in for cord blood collection. It is not as if the quality of the stem cells in these situations will be inferior, but the procedure is not done simply to avoid compounding the mother’s problems."


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