Analysis of stored and transplanted cord blood units from KoreaCORD: reappraisal of banking guidelines and selection strategy

BACKGROUND: We analyzed the characteristics of stored and transplanted cord blood (CB) units from the Korean network for public CB donation (KoreaCORD) to reassess the banking guidelines and optimize CB selection based on cell dose and human leukocyte antigen (HLA) mismatching. STUDY DESIGN AND METHODS: We retrospectively reviewed data, with regard to total nucleated cell (TNC) count and HLA match in the KoreaCORD registry from August 2001 to December 2010. RESULTS: A total of 21,914 CB units have been registered, of which 904 units (4.1%) contained less than 5 × 108 TNCs, which did not meet the present storage criteria for public CB banking in Korea. Although the proportion of stored CBs providing TNC of 5 × 108 to 7.9 × 108 was 45.7%, only 22.0% of all transplanted CBs were derived from these stored CBs. In the single CB transplantation setting, 79% (85/108) of CB units provided 4 × 107 TNCs/kg or more in the transplanted one-mismatch (1-MM) CB units and 51% (19/37) of CBs provided 6 × 107 TNCs/kg or more in the transplanted 2-MM CB units. CONCLUSIONS: The minimal requirement of TNCs for banking of CB units for public banking should be evaluated and increased to support the selection of CB units with higher cell doses, especially for use in the 1- and 2-MM transplant settings.