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Cord blood is collected at each one of
our collection sites
by trained National Cord Blood Program staff.
Minutes after a child’s birth and after the umbilical cord is cut, the placenta and its attached portion of the cord are delivered. With maternal assent to collect the cord blood, National Cord Blood Program staff move the placenta to an adjacent laboratory, where they collect the cord blood into a sterile plastic bag, much like those used for blood transfusion. Because they collect cord blood from the delivered placenta, no risk is incurred by mother or child. An NCBP nurse then explains all aspects of the Program to the mother and requests her consent to donate the cord blood. A full informed consent is required by the NCBP FDA IND exemption and research protocol. Donation of the blood from a single placenta becomes a unique cord blood unit. [See more details in Cord Blood Collections and in Cord Blood Q&A.]
Processing cord blood.
Once each day, the cord blood units are transferred from the collection sites to the NCBP laboratories, where several small samples are removed for typing and testing and the unit is processed for freezing and storage.We remove excess red blood cells and plasma using the AutoXPress (AXP) system (ThermoGenesis) to reduce the volume of each cord blood unit to 20 ml (equal to about 4 teaspoonfuls). That volume contains nearly all of the mononuclear blood cells present in the original collection, including the hematopoietic (blood-forming) stem cells. We combine this cell suspension with a preservative (DMSO) that protects the cells from damage during freezing. The “cryoprotected” cells are then transferred to a specially designed freezer bag and sealed into an overwrap bag for individual quarantine in a BioArchiveTM (ThermoGenesis)freezer.
Cord blood units are frozen and stored
at -196°C until needed.
The cord blood is frozen and stored by NCBP in liquid nitrogen freezers designed especially for cord blood units. The BioArchive is a robotic freezer that controls and monitors the rate of freezing, then stores the unit in liquid nitrogen and provides quick access to stored units whenever needed, all under computer control and with complete documentation.
When a transplant center requests a matched cord blood unit for a patient, the available inventory of cord blood units is “searched” for matches to the patient. The best matching unit (or units) can be selected, reported, confirmed and delivered rapidly upon request.
Transplant teams submit “Search Requests” to the National Cord Blood Program on behalf of their patients for us to find whether we have suitable cord blood units in the inventory. In additional to our own, two other means for searching our inventory are now available. One, through BMDW (Bone Marrow Donors Worldwide), an international catalogue of bone marrow donors and cord blood units whose search engine finds matches and provides the IDs and Banks (or Registries) of the matched bone marrow or cord blood donors to the requesting Transplant Centers. The other is through the Single Point of Access of the National Cord Blood Inventory, operated by the NMDP (National Marrow Donor Program), now called “Be the Match” Registry. This mechanism is described under the C.W. Bill Young Cell Transplantation Program. (Please see the BMDW, HRSA and NMDP websites for more information). When a matched unit list is forwarded and the patient and his/her transplant physicians decide to proceed to transplant, NCBP confirms the HLA typing of both the cord blood unit and the patient (at no extra charge to the patient). Confirmatory typing of the cord blood is performed on a sample of the unit’s contents using sealed tubing segments, integral to the freezing bag. This confirmation ensures that no mistakes were made in the labeling or HLA typing of the unit. If the unit’s information is shown to be correct and the unit is ordered for the patient, it is shipped in a liquid-nitrogen-cooled container (Dry-Shipper) with continuous monitoring of the internal temperature. The Transplant Center receives the unit before the patient begins the preparatory treatment for the transplant. Thus, the Center can make sure that the correct unit arrived in good condition without putting the patient at any risk.
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