Impact of length of cryopreservation and origin of cord blood units on hematologic recovery following cord blood transplantation

• Published in: Bone marrow transplantation Vol. 50; no. 6; pp. 818 - 821
• Main Authors: 栗田 尚樹, 千葉 滋, Kurita Naoki, Frassoni Francesco, Chiba Shigeru, Podestà Marina
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01.06.2015; Nature Publishing Group UK
• Subjects: 13/31; 631/532/1542; 692/308/2171; Adult; Aged; Banking; Blood; Blood Preservation; Bone marrow; CD34 antigen; Cell Biology; Cord blood; Cord Blood Stem Cell Transplantation; Cryopreservation; Engraftment; Female; Fetal blood; Fetal Blood - immunology; Fetal blood transplantation; Freezing; Graft vs Tumor Effect - immunology; Health aspects; Hematology; Hematopoiesis - immunology; Humans; Internal Medicine; Leukocytes (neutrophilic); Male; Malignancy; Medicine; Medicine & Public Health; Middle Aged; Multiple Myeloma - immunology; Multiple Myeloma - therapy; Myeloid Cells - immunology; Neutrophils; original-article; Protection and preservation; Public Health; Recovery; Recovery of Function - immunology; Retrospective Studies; Stem cell transplantation; Stem Cells; T-Lymphocytes, Regulatory - immunology; Thawing; Time Factors; Transplantation; Transplants & implants; Japan
• ISSN: 0268-3369; 1476-5365; 1476-5365
• DOI: 10.1038/bmt.2015.56

As the history of the cord blood banking system has lengthened, the number of cord blood units (CBUs) cryopreserved for years has increased. The global expansion of cord blood banking resulted in active international exchange of CBUs. To determine whether long-term cryopreservation and international shipment of CBUs affect the quality of the units and outcome after transplantation, we retrospectively analyzed the quality of 95 CBUs and the hematologic recovery of 127 patients with hematological malignancy following single-unit cord blood transplantation. Of the 127 CBUs used to transplant, 42 units were cryopreserved for long periods (5–11.8 years), and 44 units were shipped from distant countries. We found that length of cryopreservation and origin of CBUs did not affect the ratio of viable total-nucleated cells after thawing. Also, neutrophil engraftment was not affected by long-term cryopreservation (> 5 years) or origin (from distant countries), (hazard ratio, 0.91 and 1.2; P=0.65 and 0.41; respectively). The number of CD34+ cells before freezing (> 1.4 cells/kg recipient) was the only factor that enhanced neutrophil engraftment (hazard ratio, 1.8; P<0.01). This suggests that length of cryopreservation and origin need not be prioritized over the CD34+ cell dose when selecting CBUs.