Short-term liquid storage of umbilical cord blood

BACKGROUND: Processing and banking of umbilical cord blood requires the development of methods for short-term liquid storage. This study examines the conditions (temperature, time, and storage solution) for optimal storage of cord blood. STUDY DESIGN AND METHODS: Cord blood obtained from normal donors was collected and divided into aliquots. Some of the aliquots were supplemented with a storage solution and undiluted cord blood was used as a control. MNC counts, percentage of cells that are CD34+45+, frequency of CFU-GM, and solution pH were monitored for up to 72 hours in storage at 4°C and room temperature. RESULTS: MNC counts, CD34+45+ cell recovery, and frequency of CFU-GM were all improved in samples diluted with a storage medium when compared to undiluted controls. MNC counts were higher when cells were stored at 4°C. MNC counts and the frequency of CFU-GM were reduced at 72 hours when compared with 24 hours. CONCLUSIONS: These results indicate that the recovery of cells from cord blood can be improved if samples are stored using a storage solution for 24 hours without significant cell losses. Some of the solutions determined to be effective in maintaining viability are approved for human applications, although not specifically cord blood preservation.