According to the research published in “The Journal Bone Marrow Transplants”
The outcome of the research done at University of Colorado Cancer Center on Leukemia patients who received bone marrow transplants from unrelated donors in the year 2009- 2014, when monitored after 3 years showed 44% of severe chronic graft versus host disease. Whereas, in the case of patients who received matched unrelated donor umbilical cord blood transplants (CBT) the graft versus host disease occurred only in 8% of the cases.
The other advantages, the patients on cord blood transplants (CBT) received were there dependence of immunosuppression drugs was minimal and they also were less prone to iatrogenic and late infections which are commonly seen in transplant patients. Along with the mentioned optimistic highlights witnessed the Published research by New England Journal of Medicine also showed edge of cord blood units in survival rates and relapse rates between the two treatment protocols administered.
Dr. Jonathan Gutman, the investigator at CU Cancer Centre and Clinical Director of Allogeneic Stem Cell Transplant at the University of Colorado Hospital said that, during an allogeneic transplant, the infused stem cells has the potential to attack the patient’s blood system in Leukemia. This attack is known as the graft versus host disease and this can turn out even to be fatal. But, when a patient receives an infusion of cord blood from an unrelated donor for a transplant the implication as graft versus host disease is less likely.
In a standardized replacement therapy against Leukemia the patient’s affected stem cells are wiped out and fresh stem cells from four different sources were infused into the patient. The four sources are a matched stem cell from a related donor- this can be stem cell extracted from a close family member, a matched donor- from an unrelated donor from a database of 25 million who are willing to donate, cord blood units from an unrelated donor preserved at a bank and haploidentical stem cells from a half match with a related donor. Closer the match lesser the attack on the patient’s system and thereby can bring a better treatment outcome.
Apart from the above-mentioned benefits of cord blood usage in transplants, the other following advantages of cord blood over bone marrow showing a positive outcome is listed below:
A comparative study between Bone Marrow & Cord Blood Stem cells in transplants
|BONE MARROW STEM CELLS||CORD BLOOD STEM CELLS|
|Donation of Bone marrow requires surgery under general anesthesia. Donors may experience temporary pain.||Umbilical cord stem cell collection is easy, painless done when a baby is born and cord blood donation poses no medical risk to mother or infant|
|A transplant requires donation of a quart or more of bone marrow volume mixed with blood||A small volume (sometimes few ounces) can be used for transplantation. The number of cells needed depends on the recipient’s weight.|
|After a formal search is started, it usually takes 3 or more months to transplant, if a donor is available.||When a match is found it can take only 2-3 days for confirmatory and special testing for shipment to the Transplant Center (less than 24 hours in an emergency).|
|Potential donors may no longer be available or may have withdrawn consent. Donor must be found and retested to confirm the HLA typing and infectious disease results and to confirm that the donor is still willing and able to donate bone marrow. Significant donor attrition||Once frozen, a cord blood unit is available until used. There is no donor attrition.|
|Bone marrow is used fresh so there is limited shelf-life which is measured in hours||Cord blood units are cryopreserved. Frozen cord blood has been transplanted successfully with no expiry|
|Patient must begin conditioning before the bone marrow harvest.||Cord blood graft can be shipped to the transplant center before the patient enters the hospital and begins|
|Coordination between donation and transplant is critical and complex.||Coordination is simple. Cord blood units are shipped on demand.|
|Latent viral infection in the donor is common (i.e. CMV > 50% in U.S. adult donors).||Latent viral infection in the cord blood donor is rare (i.e. CMV <1% in U.S.).|
|No risk of transplanting a genetic disease||There is a small probability that a rare, unrecognized genetic disease affecting the blood or immune system of the baby may be given with the cord blood transplant.|
|Generally requires a perfect match between donor and recipient for 8/8 HLA||HLA matching of 4/6 is sufficient for a cord blood to be used for transplants, making it easier to find a suitable match|
Through the years’ cord blood units were used in cases where finding a match was difficult, most centers also reserved cord blood units for the worst transplants. Due to primitive exposure to stem cell transplant in those times, the reputation of cord blood dwindled amidst the medical practitioners, moreover cost also is a main driving factor in the usage of cord blood units. However, research data over the years adds to the evidence-based claim that cord blood according to current studies is equal or even more preferred to other sources in cases of matched, unrelated donors.The support offered to the patient post the infusion in the case of cord blood could be a little longer as these younger cells might take a little longer to engraft. If the transplant is done in a more evolved setup cord blood proves itself undisputedly to be the more preferred choice or rather even the first choice in the case where a matched related donor is not available.