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

Abstract

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 (4 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 (4 1.4 cells/kg recipient) was the only factor that enhanced neutrophil engraftment (hazard ratio, 1.8; P o 0.01). This suggests that length of cryopreservation and origin need not be prioritized over the CD34 + cell dose when selecting CBUs.

Impact of starting material (fresh versus cryopreserved marrow) on mesenchymal stem cell culture

“…Marrow is usually cryopreserved in 10% DMSO, and studies have shown that marrow, as well as peripheral blood stem cells and umbilical cord blood, may remain cryopreserved for a long period of time (>10 years) while retaining stem cell/progenitor activities for use in clinical practice. [12][13][14] Shen and colleagues demonstrated that marrow preserved for 23 to 25 years was effective for MSC culture production with adequate growth characteristics and adequate amounts of adherent, healthy MSCs. 15 Those authors investigated old frozen marrow specimens as starting material (n 5 20) for MSCs, but the controls (n 5 20) were not paired from the same donors.…”

Long-Term Cryopreservation Does Not Affect Quality of Peripheral Blood Stem Cell Grafts: A Comparative Study of Native, Short-Term and Long-Term Cryopreserved Haematopoietic Stem Cells

“…The capability of CD34þ cells to be stored for more than 10 years is proven in cord blood units and reviewed extensively [24][25][26][27] , but these results are not directly comparable with PBSC, where the CD34þ cells are being mobilized from their natural environment and cryopreserved accompanied with highly activated neutrophils. Our study showed that the viability of leukocytes declined with long-term storage (68% after 10 years); however, the viability of mononuclear and CD34þ cells was retained with <10% decrease in comparison to native products.…”

Umbilical Cord Blood Cells for Perinatal Brain Injury: The Right Cells at the Right Time?

“…Umbilical cord blood (UCB) is a particularly promising source of stem and progenitor cells that is appealing for treatment of perinatal brain injury-UCB is readily available at birth for routine collection, particularly in situations of compromised (preterm or term asphyxia) births; contains large numbers of mononuclear cells with a heterogeneous population of stem and progenitor cells [76]; has low immunogenicity and low risk of rejection, therefore allowing the potential for allogeneic administration [77]. UCB cells demonstrate high plasticity with an eightfold greater proliferation potential compared to other cell sources such as bone marrow [78]; and can be stored for long periods of time, with studies showing that, after 10+ years of cryopreservation, viable cell recovery is still very high [79].…”