Simard C, Bonnaure G, Fournier D, Néron S. An objective flow cytometry method to rapidly determine cord blood potency in cryopreserved units.
Transfusion 2019;
59:2074-2083. [PMID:
30802338 DOI:
10.1111/trf.15220]
[Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 01/25/2019] [Accepted: 01/28/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND
Cord blood banks have to determine the regenerative potential of cord blood units (CBUs) on a representative sample of the cryopreserved product before release to the transplant center. Potency can be measured by using a colony-forming unit (CFU) method, which delays the release of CBU by 7 to 14 days. To accelerate CBU qualification, we have developed a rapid method to assess the response of CD34 cells to interleukin (IL)-3. Flow cytometry was used to measure IL-3-induced STAT5 phosphorylation within CD34-cells. This IL-3 test was compared to the CFU method, as well as the aldehyde dehydrogenase (ALDH) enzyme-based assay.
STUDY DESIGN AND METHODS
Ten cryopreserved CBUs were analyzed for their contents in CD34 and CD45 viable cells, total CFUs, ADLHbright cells, and IL-3-responsive CD34+ cells. Extreme and mild warming event scenarios were simulated on CBUs and used as poor-quality samples. Segments, tubes, and bags from five CBUs were compared for their potency using IL-3 and CFU methods.
RESULTS
The IL-3 test was accurate in identifying the samples handled following standard operating procedures and those subjected to extreme warming events. Based on these results, a threshold of 55% of IL-3-responsive CD34 cells was established to identify good-quality samples. The IL-3 test was also the most sensitive to detect samples subjected to milder warming events.
CONCLUSIONS
Our new method for determining CBU functionality is rapid, unbiased, and robust. The IL-3 test described herein fulfills the requirements for validation, and we intend to implement this method in our cord blood bank facility.
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