Repurposing the public cord blood bank inventory in Korea to enhance cord blood use

To enhance public cord blood (CB) use, we examined the current status of CB banking and tried to suggest revision of the banking standard. We retrospectively analyzed the use of stored public CB units between 2011 and 2016 using data from the CB information center in Korea. A total of 19,871 CB units were registered, and 363 units were selected for transplantation. The transplanted CB units contained significantly higher numbers of CD34+ cells than the average numbers in the stored CB units (5.5 x 10<^>6 vs. 3.2 x 10<^>6, p < 0.01). They also contained more total nucleated cells (TNCs) than the average of the stored CB units (13.7 x 10<^>8 vs. 10.7 x 10<^>8, p < 0.01). Only 49% of the stored CB units contained > 10 x 10<^>8 TNCs, while 81% of the units transplanted contained > 10 x 10<^>8 TNCs. The average length of cryopreservation of the transplanted CB units was 4.58 years and 95% of them had been stored for less than 10 years. During the study period, 18,763 CB units were requested for research, but only 5,888 were released. This discrepancy was mostly due to errors in regulatory and/or networking elements of the CB supply system. The data suggest that preserving CB units for less than 10 years and increasing the required minimum TNC count to 10 x 10<^>8 would produce an inventory containing units that were more useful for CBT. CB units that did not meet the requisite quality standards could be used for research, and systems for their fair distribution to researchers are needed.