What Factors Should I Consider When I Choose a Cord Blood Bank?
To understand what the critical factors are, you first need to know what a cord blood bank does to obtain, process and preserve the cord blood sample. You might find the information provided by cord blood banks to be complex and overwhelming. In fact, what is involved is quite simple.
All cord blood banks follow regulations and standards that are set by the federal government and the organization that is responsible for their accreditation. First of all, expectant mothers are screened for their eligibility (which usually means being free of transmissible diseases) to provide cord blood for banking. This is governed by these regulations and standards, and does not vary significantly with the blood bank. The only difference between cord blood banks lies in the quality of cord blood processing offered by the bank. Cord blood processing is the extraction of nucleated cells (stem cells are nucleated cells) from the cord blood sample collected at birth by the health care provider. Because there are various scientifically accepted methods for processing cord blood, cord blood samples at different facilities can be processed differently based on the method and techniques the facilities use. This processing phase is the crucial procedure that determines the number of cells saved from the cord blood sample. The resulting processed cord blood unit undergoes cryopreservation (freezing) in preparation for long-term storage. All cord blood banks follow similar cryopreservation procedures and store cord blood units at very low temperatures. After the cord blood unit is properly cryopreserved and stored, cell viability, the number of living cells, remains largely unchanged. Hence the quality of the stem cell product does not vary with storage facility.To help you better understand the one crucial factor under the control of blood banks that affects the quality of the stem cell product, namely, processing, we have provided an easy-to-follow Q&A below. This will help guide you in your choice of a blood bank that suits your needs. It provides information about the factors that you should consider when choosing your cord blood bank. Cord blood banking for a person is a once-only opportunity following birth so we strongly encourage families to take time to understand the purpose and nature of cord blood banking. Please review the questions and answers in the order presented to better understand how the factors influence each other.
- Why should I bank my baby’s cord blood stem cells?
Cord blood contains life-saving cells. These cells can be thought of as a form of life insurance as they could save the life of the baby and/or family member(s) if the need for a transplant arises.
- Can you guarantee that the banked cord blood stem cells can be used when my baby or a family member needs the cells?
No, unfortunately, there is no guarantee that the banked cord blood stem cells can be used. Eligibility for transplantation is determined by many factors and the transplant physician must review these requirements and criteria before making a decision to transplant. A cord blood bank can only increase the likelihood of the banked cord blood unit being usable by extracting the maximum number of cells possible during processing of the cord blood.
- Who determines if the banked cells are enough for a transplant?
The attending transplant physician who is treating the patient will determine if the banked cells are sufficient for the transplant.
- What is the most important factor that the physician will consider when determining whether the banked cord blood stem cells can be used to treat the patient?
The most important factor is the cell dose or number. The physician needs to calculate this by dividing the number of banked cells (generally speaking, the number of total nucleated cells) by the body weight (in kilograms) of the patient to assess whether this number meets the criteria for the transplant. This calculation means that a heavier patient will need more cells. In other words, when your baby is very young the banked cord blood unit may contain a sufficient number of cells to meet the eligibility criteria but, as your baby grows, this number may not be adequate. Obviously, it is extremely important that the maximum number of cells be extracted and banked to increase the chances that eligibility requirements are met.
- How can we save more cells then?
There are two factors that affect the number of cells that can be banked. First of all is the volume of cord blood collected at the baby’s birth. Generally but not invariably, a larger cord blood volume will contain more cells. The second factor is the number of cells extracted from the cord blood sample by the cord blood bank during the processing phase. A cord blood bank cannot bank more cells than the number collected at birth but, on the other hand, it can extract fewer cells than were collected by losing cells during processing. Hence, processing quality is the crucial factor under the control of the blood bank influencing the opportunity to save life through stem cell transplantation.
- How well was my baby’s cord blood processed?
Cord blood banks often lay claim to banking quality by providing a list of facts which they consider to be important, but which often confuse readers and make comparisons between banks more difficult. There is, however, a very simple and reliable way to determine how well the cord blood has been processed.
The first step in processing cord blood to extract the maximum number of nucleated cells is to reduce the volume of the sample. This ensures the cord blood unit is highly concentrated in nucleated cells and contaminated with the least amount of unwanted red blood cells prior to cryopreservation and storage. A direct and simple way to determine how well a cord blood sample has been processed is to calculate the proportion of nucleated cells that has been obtained from the original sample:
Percentage yield (extraction rate) of cells =
Higher percentage yields (extraction rates) of cells indicate minimal cell loss during the processing phase, which in turn means that the cord blood sample has been effectively processed.It is worth mentioning that the number of cells in each cord blood sample may vary significantly. Hence, the effectiveness of processing must be calculated in percentages for it to be meaningful and comparable among various samples and cord blood banks. This formula is the only measure that reflects processing/banking quality and is independent of processing methods (automated or manual) or the number of cells and volume of cord blood that was initially collected.
*excluding very small amounts of cells which are used for tests.
- Should I get a report of the yield (extraction rate) of total nucleated cells after my baby’s cord blood is processed?
Yes, all families have the right to this information because it is the only way for them to know how well the cord blood sample has been processed. Unfortunately, few cord blood banks report the yield. We believe it is important for expectant parents interested in banking their baby’s cord blood to inquire whether the cord blood bank reports the yield (extraction rate) of total nucleated cells and whether there is any quality guarantee regarding the processing of the sample. (Note that this is different from a guarantee of transplant success.) If the cord blood bank claims that its processing is high quality or superior but fails to provide reports disclosing the yield of cells for all processed samples, parents should consider investigating other facilities.
Selecting the right cord blood bank means a better chance of saving more cells after the initial collection of cord blood, leading in turn to increased chances of life-saving success if a transplant is needed later. Clearly the right choice for prospective parents is the blood bank that saves more stem cells (percentage yield of total nucleated cells) by maximizing their extraction during processing.