“However worried whether the units will remain viable till the baby is grown”.
Transplantation of cord blood is a clinically effective form of treatment for many cancer and blood disease patients requiring stem cell transplantation. To date, cord blood transplants have treated more than 30,000 patients.
Blood-forming (hematopoietic) stem cells and progenitor cells are the precious ingredients in cord blood that can replicate and diversify to replace the entire immune system of a patient. These cells are uncommon, consisting less than 1% of cells in umbilical cord blood, but there are millions of blood-forming stem and progenitor cells in a typical cord blood collection.
A frequently asked question about collected cord blood is how long can stem and progenitor cells be kept frozen and still be viable when thawed?
A moving target is the maximum storage time for stem cells in the cord blood. In fact, as the number is likely to change, most cord blood banks do not label the units with an expiry date.
Scientists have reported, however, that there is no expiration date for cryogenically preserved cells, and frozen cord blood may be stored indefinitely. Two key facts supporting this:
- Stem cells of the cord blood are stored at or below -196 degrees Celsius where biological activity stops.
- For 50 + years, other types of cells and sperm were stored and remained viable when thawed.
On October 6, 1988, the first cord blood transplant was conducted in Paris. Over 1 million cord blood units have since been collected and stored throughout the world in public and family banks.
In theory, if the umbilical cord blood stem and progenitor cells were properly cryopreserved, they should be kept in a frozen state for many decades, if not longer, with subsequent recovery of viable stem and progenitor cells. This depends practically on the quality of the cryopreservation process. It depends on whether the storage facility has ensured the maintenance of the cryogenic nitrogen tanks at a very lower temperature constant. Finally, it depends on the laboratory staff’s ability and the thawing process of reviving cells.
Over the years since, at 5 years, 10 years, 15 years and most recently 23.5 years after the cells were frozen in cryopreserved form, we have shown effective cell recovery. The accuracy of these tests is based on the fact that we have continuous custody of these cells, and with the same tests as their pre-freeze measurements we have carried out their post-thaw analysis.
Cord blood stem cell banking began in 1994 when the New York Blood Center Cord Blood Bank was founded. Over the past two decades, the field of umbilical cord blood storage has matured significantly. We keep learning more about the long-term consequences of cryo-preservation on cells, leading to increased storage times.
To date, the longest study published by Broxmeyer et al in 2011 found that cyro – preserved stem cells were grafted as expected for 22.5 years. No significant loss of recovery or proliferation of stem cells occurred.
Clinical studies may take some time to demonstrate the viability of long-term storage stem cells that we have established in the laboratory. Clinical evidence would require treatment of patients who had been in storage for decades with cord blood units. But banks of public cord blood tend not to use older collections of stored cord blood if they have newer ones.
Therefore, the proof of long-term preservation of cord blood stem cells provided by the public or the private cord blood banks can assure the parents as well as the family members that the cord blood can be many years in the basic state. Also, it can be used for the treatment whenever it is needed.
Author Bio: Adriana Frederick has been associated with the health industry for a long time. In her leisure, she loves writing articles. Through her articles, you can obtain knowledge on various stem cell preservation, Stem cell banking, cord blood banking.