A validation study of new cryopreservation bags for implementation in a blood and marrow transplant laboratory.

BACKGROUND: A new cryopreservation bag for hematopoietic cell transplantation requires validation as a safe alternative to the bag currently being used in the laboratory. STUDY DESIGN AND METHODS: The new bag was validated using both laboratory and clinical criteria. Laboratory validation proceeded using paired samples of mononuclear cells processed using standard procedures. Cells cryopreserved in the new and old bags were compared for viability, cell counts, CD34 enumeration, colony-forming unit assays, and bag integrity. After completion of laboratory investigations, engraftment with the new bags was followed and compared to historical engraftment using the old bags.
RESULTS: There were no significant differences between the old and new bags detected using laboratory studies. Bag integrity was equivalent. The validation data suggested impaired cell function after cryopreservation in the new bags, but there were no significant differences in engraftment potential using either material. Days to engraftment was longer using the new bags, but statistical analysis revealed an association with CD34 dose and not with cryopreservation bag type.
CONCLUSION: The new bags were noninferior to the old bags. A change in cryopreservation bag type may appear to affect cell function and potentially affect engraftment. Multiple analyses may be needed to understand the effect of cell processing changes.