How can cord blood stem cells of a baby be preserved?
Q: I am pregnant and suffering from Immune Thrombocytopenic Purpura. For the safety of my baby's future my husband and I are thinking of freezing the cord blood stem cells. Could you please tell me about preserving the cord blood stem cells for a baby?
A:Stem cells are primitive cells with the ability to both multiply and differentiate into specific types of cells like blood cells (white blood cells, red blood cells and platelets), neurologic stem cells (forming neural tissue) and blood vessel stem cells or most any tissue. They can be collected from the bone marrow, peripheral blood, or umbilical cord blood. Cord blood is the remaining blood from the baby's umbilical cord and placenta after birth. Some of the current indications for stem cell treatment include: -Non-malignant hematologic disorders like (aplastic anaemia, Fanconi’s anaemia, thalassaemia, sickle cell anaemia, PNH) -Malignant diseases like leukaemia, lymphoma, multiple myeloma -Immune deficiency disorders like severe combined immunodeficiency, Wiskott-Aldrich syndrome Chédiak-Higashi syndrome, chronic granulomatous disease -Other malignancies: Neuroblastoma, small cell carcinoma of lung, carcinoma colon, testicular carcinoma, Uterine & ovarian cancers, malignant melanoma, soft tissue sarcoma -Liposomal storage disorders -Histiocytic disorders Cord blood stem cells have the advantage of being present in greater number and having a better capacity to divide compared with peripheral blood or bone marrow stem cells of adults. Moreover, as these cells are immunologically immature they allow the crossing of immunologic barriers that may not be possible with adult stem cells i.e. greater HLA disparity can be tolerated. The one big disadvantage of cord blood stem cells is the low volume of cells harvested which may make transplant difficult in an adult patient. There are several ways of collecting cord blood. Following the birth of a baby, the umbilical cord is clamped and the placenta delivered. The placenta is kept on a supporting frame and the umbilical cord cleaned with iodine & alcohol. The cord blood (usually 60-120 ml) is drained through a needle placed into the umbilical vein and collected in a blood bag. Another method involves collecting the cord blood following delivery of the baby, while the placenta is still in the mothers uterus. The advantage of this technique includes earlier collection of blood before it can begin to clot and ease of blood collection as uterine contractions push the blood out. But this may interfere with post-partum care of the baby and the mother. The volume of cord blood collected from a single placenta is called a cord blood unit. The cord blood is first tested - HLA typing, cell counts and infections (HIV, cytomegalovirus, hepatitis virus etc.) and then frozen and stored in liquid nitrogen for future use. When required, the cord blood unit is thawed and infused via a vein into the recipient. There are a large number of patients who are diagnosed with diseases that are potentially curable by a bone marrow transplant. The constraint is the absence of an HLA or immunologically matched donor. Using a family members stored stem cells gives the patient a higher probability of finding an exact or acceptable match for transplantation. Those in favour of cord blood banking say: -There is a possibility in future that it might save your baby's or another family members life -The only time that cord blood can be banked is at the time of birth -The process of cord blood collection is simple, painless, and harmless to both the baby and mother. It is of use if a family member has a condition that can be treated with a stem cell transplant Future advances in medical science may permit stem cells to treat even more diseases The issue of cord blood storage for future private use is controversial when it is purely speculative and no specific family member has been identified as needing a transplant. The American Academy of Pediatrics states that there is no strong evidence to recommend routine cord blood banking for an infants future use. No accurate estimates exist of the likelihood of children to need their own stored cells and the odds of needing cord blood for medical treatment is very, very slim. Also, the cost of cord blood banking is very high. The donor cannot use the cord blood if he/she has a genetic disease because the same disease would be returned with the transplant. Moreover, autologous (self) cord blood transplant for children with leukaemia is not recommended.