A validation study of starting use of new freezing bags in cord blood bank / 国际检验医学杂志

Objective To verify whether the storage bag can reach the use requirement of cord blood freezing storage by conduc-ting a series of tests before staring use of new type cryopreservation bag for cord blood.Methods According to the standard opera-tion procedure,28 new type cryopreservation bags were extracted.The cord blood units were performed the cryostorage and thaw for rewarming according to the standard operating procedures.Then the physical integrity and various quality indicators of cord blood in bag were detected,including the nucleated cell viability,cell recovery rate,CD34-positive cell,colony-forming cultivation of stem cells,sterility test and verification of actual load volume.Results All the tested storage bags passed the integrity test,and the various testing indicators of the preserved cells conformed to the use requirements.Conclusion The new type storage bag has the same performance and effect to original bag,it is verified that the maximum loading volume of 50 mL(for 50 mL specification of storage bag)and 80mL(for 250mL specification of storage bag)is safe.

Analysis of post-thaw infused cell dose for predicting engraftment after unrelated cord blood transplantation / 中国实验血液学杂志

This study was purposed to investigate the role of post-thaw infused donor cells for predicting engraftment and hematopoietic reconstitution after unrelated cord blood transplantation (UCBT). The retrospective analysis was performed on clinical data of 97 children with malignant or non-malignant diseases received single unit UCBT from August 1999 to April 2010. The impact of pre-freezing and post-thaw cell dose of total nucleated cells (TNC), CD34(+) cells and colony-forming units-granulocyte/macrophage (CFU-GM) on engraftment and hematological recovery after UCBT was analyzed. Unrelated donors were from Guangzhou cord blood bank (GZCBB) entirely. The results indicated that the pre-freezing TNC (/kg) (mean ± SD: 7.65 × 10⁷ ± 4.26 × 10⁷; median: 6.34 × 10⁷), CD34(+)cells (/kg) (mean ± SD: 4.64 × 10(5) ± 4.47 × 10⁵; median: 3.03 × 10⁵) and CFU-GM (/kg) (mean ± SD: 0.79 × 10⁵ ± 1.09 × 10⁵; median: 0.57 × 10⁵) showed a good correlation with their post-thaw counterparts including TNC(/kg) (mean ± SD: 6.98 × 10⁷ ± 4.12 × 10⁷; median: 6.00 × 10⁷), CD34(+)cells (/kg)(Mean ± SD: 6.86 × 10⁵ ± 8.56 × 10⁵; Median: 4.17 × 10⁵), and CFU-GM (/kg) (mean ± SD: 0.52 × 10⁵ ± 0.52 × 10⁵; median: 0.39 × 10⁵) (r = 0.952, p < 0.001; r = 0.794, p < 0.001; r = 0.478, p < 0.001). Either the pre-freezing or post-thaw number of infused CFU-GM was significant higher in patients who achieved engraftment (n = 70) than those who suffered graft failure (n = 22) (p = 0.023 and 0.011, respectively), but no significant difference of TNC and CD34(+) cells dose (pre-freezing or post-thaw) were found between these two groups. Pre-freezing CFU-GM, TNC, CD34(+) cell dose negatively correlated with the time of neutrophil engraftment (r = -0.285, p = 0.018; r = -0.396, p = 0.002; r = -0.373, p = 0.002), as well as the post-thaw number of TNC and CD34(+) cells (r = -0.260, p = 0.031; r = -0.483, p < 0.001), whereas only pre-freezing CD34(+) cells showed a significant correlation with platelet engraftment time (r = -0.352, p = 0.013). It is concluded that the CFU-GM amount is useful for predicting engraftment of UCBT, while pre-freezing hematopoietic cell doses show superior correlation with the speed of engraftment and hematopoietic reconstitution than their post-thaw counterparts in pediatric recipients, suggesting that it is essential to perform hematopoietic potency assay on each cord blood unit prior to listing or release for administration.

Analysis of maternal and neonatal factors associated with hematopoietic reconstruction potential in umbilical cord blood units / 中国实验血液学杂志

Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells for transplantation with success being associated with the total nucleated cell (TNC) count, CD34(+) cells and colony-forming unit-granulocyte-macrophage (CFU-GM) content infused. This study was purposed to clarify the impact of maternal and neonatal factors on hematopoietic potential of UCB product. UCB samples were screened, processed, tested and cryopreserved according to the Standard Operation Procedure (SOP) of Guangzhou cord blood bank (GZCBB). Relationship of hematopoietic cell parameters with maternal and neonatal characteristics for 4615 UCB units was analyzed retrospectively. The results showed that both collected volume (Mean ± SD: 95.23 ± 22.42 ml; Median: 91.85 ml) and initial TNC [Mean ± SD: (1.34 ± 0.49) × 10(9); Median: 1.25 × 10(9)] correlated well with postprocessed TNC [Mean ± SD: (1.21 ± 0.42) × 10(9); Median: 1.14 × 10(9); p < 0.001], CD34(+)count [Mean ± SD: (5.14 ± 4.55) × 10(6); Median: 4.08 × 10(6); p < 0.001] and CFU-GM content [Mean ± SD: (9.72 ± 8.66) × 10(5); Median: 7.53 × 10(5); p < 0.001]. As for donor factors, only infant birth weight correlated strongly with volume collected and all hematopoietic cell parameters (p < 0.001). UCB samples from bigger babies had higher collected volume, TNC, CD34(+) count and CFU-GM content (p < 0.001). Mother's age had no correlation with all the above parameters. Gestational age correlated positively with initial/postprocessed TNC (p < 0.001) and negatively with CD34(+) count (p = 0.04), but no relation with collected volume and CFU-GM content. Cesarean section produced superior volume (Mean ± SD: 97.05 ± 22.23 ml vs 92.53 ± 22.43 ml; Median: 94.08 ml vs 88.82 ml; p < 0.001), but inferior cell count than vaginal delivery (p < 0.001). Male infants had more initial volume and CD34(+) count (Mean ± SD: 96.41 ± 22.31 ml vs 93.95 ± 22.47 ml; Median: 93.27 ml vs 90.14 ml; p < 0.001); [Mean ± SD: (5.28 ± 5.04) × 10(6) vs (5.00 ± 3.94) × 10(6); Median: 4.18 × 10(6) vs 3.94 × 10(6); p < = 0.042], but lower initial and postprocessed TNC than female ones [Mean ± SD: (1.31 ± 0.50) × 10(9) vs (1.37 ± 0.47) × 10(9); Median: 1.22 × 10(9) vs 1.28 × 10(9); p < 0.001]; [Mean ± SD: (1.18 ± 0.42) × 10(9) vs (1.24 ± 0.41) × 10(9); Median: 1.10 × 10(9) vs 1.17 × 10(9); p < 0.001], while no significant difference of CFU-GM were found between male and female infants. It is concluded that these data may be helpful to optimize the UCB donor selection and improve cost efficiency of UCB bank resource. The heavier infants after vaginal delivery should be selected and large-volume units with higher TNC should be chosen at first.