Automated thawing increases recovery of colony‐forming units from banked cord blood unit grafts

BACKGROUND The cell dose infused for cord blood transplantation strongly correlates with outcomes following transplantation. Post thaw recoveries can be improved by washing cord blood units (CBUs) in dextran/albumin. Early methods used a labor‐intensive manual process. We have recently developed and validated an automated washing method. We now report our results of a study comparing cellular recoveries achieved after manual and automated wash, as well as the impact on engraftment following allogeneic transplantation. STUDY DESIGN AND METHODS CBUs distributed by the Carolinas Cord Blood Bank for clinical use at Duke University after manual or automated wash were included in this report. Precryopreservation total nucleated cell count, total CD34+, colony‐forming units, recoveries, and sterility were analyzed by wash method. Patient age, cell dose/weight, diagnosis, conditioning regimen, immunosuppression, and time to neutrophil engraftment were also analyzed. RESULTS Manual and automated washed CBUs yielded similar total nucleated cell count and total CD34+ recoveries. Significantly higher colony‐forming units recoveries were achieved after automated washing. Patients who received CBUs washed via an automated method experienced earlier neutrophil engraftment. CONCLUSION While manual and automated washing achieved similar post thaw cellular recoveries, automated washed CBUs demonstrated higher colony‐forming unit recovery, which is an important predictor of potency and engraftment. Furthermore, we demonstrated that automated washing was associated with earlier neutrophil engraftment. Our findings favor the use of an automated wash method over a manual approach.