Impact of donor- and collection-related variables on product quality in ex utero cord blood banking

Evaluation of factors affecting total nucleated cells in umbilical cord blood collected for the Calabria Cord Blood Bank

BACKGROUND

Total nucleated cell (TNC) count is the most important biological feature to consider in assessing the quality of umbilical cord blood (UCB) for hematopoietic stem cell (HSC) transplantation. Certain obstetric factors have been reported to increase TNC count in UCB units collected for transplantation. The aim of our study was to analyze how various maternal, neonatal and obstetric factors affected TNC count in the UCBs we collected for our cord blood bank in southern Italy.

METHODS

We performed a retrospective analysis of 634 medical records of UCBs collected by Calabria Cord Blood Bank (CCBB), Reggio Calabria, Italy, between January 1, 2010, and December 31, 2016. We analyzed various maternal, neonatal and obstetric variables factors and related this factor with the characteristic of TNC.

RESULTS

We found that the average number of TNCs was significantly greater in vaginal delivery than in caesarean delivery. We also found that TNCs were higher in the 40th week of pregnancy and when Apgar 1' scores were ≤9. The effect of a newborn's gender was less evident on TNC count.

CONCLUSIONS

Knowledge of factors predictive of a higher TNC count would help cord blood banks more efficiently identify donors likely to yield high-quality UCBs for transplantation.

Impact of maternal and neonatal factors on umbilical cord CD34+ cells

Background

The achievement of optimal number of CD34⁺ umbilical cord stem cells is essential for successful umbilical cord stem cell transplantation. So the aim of this study was to assess the potential effect of both maternal and neonatal factors on the umbilical cord blood CD34⁺ cell count.

Methods

The study was done on umbilical cord blood samples obtained from 20 mothers during labor. Their ages ranged from 22 to 34 years and were subjected to history taking, physical examination of the baby and assessment of the CD34⁺ cells count in umbilical cord blood.

Results

Number of previous live births and weight of the baby had a significant effect on CD34⁺ cells count while the sex of the baby, delivery route, maternal age and gestation period had no significant effect on CD34⁺ cells count.

Conclusions

Umbilical cord blood-derived CD34⁺ cell count is better with good weight and first babies and decreased with subsequent babies.

Umbilical cord blood quality and quantity: Collection up to transplantation

Umbilical cord blood (UCB) is an attractive source of hematopoietic stem cells for transplantation in some blood disorders. One of the major factors that influence on transplantation fate is cord blood (CB) cell count, in addition to human leukocyte antigen similarity and CD34+ cell number. Here, we review the factors that could effect on quality and quantity of CBUs. Relevant English-language literatures were searched and retrieved from PubMed using the terms: CB, quality, collection, and transplantation. The numbers of total nucleated cells (TNCs) and CD34+ cells are good indicators of CB quality because they have been associated with engraftment; thereby, whatever the TNCs in a CB unit (CBU) are higher, more likely they led to successful engraftment. Many factors influence the quantity and quality of UCB units that collect after delivery. Some parameters are not in our hands, such as maternal and infant factors, and hence, we cannot change these. However, some other factors are in our authority, such as mode of collection, type and amount of anticoagulant, and time and temperature during collection to postthaw CBUs and freeze-and-thaw procedures. By optimizing the CB collection, we can improve the quantity and quality of UCB for storage and increase the likelihood of its use for transplantation.

Estimated fetal weight percentile as a tool to predict collection of cord blood units with higher cellular content: implications for prenatal selection of cord blood donors

BACKGROUND

The need for high-cellular-content cord blood units (CBUs) for allogenic transplantation is evident to improve clinical outcomes. In our environment and with current donation programs, very few collected units meet suggested clinical thresholds, making collection programs highly inefficient. To increase the clinical conversion rate, we have assessed factors influencing the cellular content of the cord blood collection and established the estimated fetal weight percentile (EFWp) as a tool to predict which deliveries will obtain higher cellular counts.

STUDY DESIGN AND METHODS

We conducted a retrospective analysis of 11,349 collected CBUs. An analysis of diagnostic efficiency (receiver operating characteristic [ROC] curve) was performed to establish the cutoffs of several obstetric and perinatal variables from which we would obtain more than 1500 × 106 total nucleated cells and 4 × 106 CD34 cells. We then calculated the optimal EFWp cutoff to increase efficiency.

RESULTS

In the univariate analysis, factors positively and significantly associated were a greater neonatal and placental weight and longer weeks of gestation. In the multivariate analysis only neonatal and placental weight remain significant (p < 0.001). The ROC curve analysis showed that the optimal EFWp cutoff is 60, which has the maximum area under the curve. Applying this, donations meeting clinical cellular numbers will increase more than 30% with respect to not using any threshold.

CONCLUSION

The EFWp predicts the quality of the collected CBUs and can be used to make a prenatal selection of the donors, therefore increasing the efficiency of umbilical cord blood collection programs.

Impact of delayed umbilical cord clamping on public cord blood donations: can we help future patients and benefit infant donors?

BACKGROUND

Cord blood (CB) is a widely accepted stem cell source and its clinical utilization depends, to a great extent, on its cell content. Birth-to-clamping (BTC) time of umbilical cord determines placental transfusion to the newborn, and the remaining blood that can be collected and banked. The 2017 Committee Opinion of the American College of Obstetrics and Gynecologists (ACOG) recommends a delay of "at least 30-60 seconds" before clamping the cord for all newborns to ensure adequate iron stores. The impact of delayed cord clamping (DCC) on public CB banking can be substantial.

STUDY DESIGN AND METHODS

Cord blood units (CBUs) collected from 1210 mothers at one hospital were evaluated for total nucleated cells (TNCs) and weight/volume based on time to clamping. Bank staff recorded BTC time in seconds as reported by obstetricians; collections were performed ex utero. Immediate clamping was defined as BTC of less than 30 seconds, whereas DCC was defined as BTC of 30 seconds or more.

RESULTS

Cord clamping was immediate in 903 (75%) and delayed in 307 (25%) deliveries. Successful recovery (% clinical CBUs) decreased 10-fold with DCC of more than 60 seconds (22% vs. 2.4%, p < 0.001). CBUs collected after DCC of more than 60 seconds had significantly lower TNC counts than those after DCC of less than 60 seconds (p < 0.0001). Furthermore, 38% to 46% of CBUs after DCC of more than 60 seconds had volume of less than 40 mL.

CONCLUSION

Our study indicates that DCC of 30 to 60 seconds has a small negative impact on collection of high-TNC-count CBUs. However, increasing BTC to more than 60 seconds decreases significantly both TNC content and volume, reducing drastically the chances of obtaining clinically useful CBUs.

Associated factors of umbilical cord blood collection quality

After 30 years of hematopoietic stem cell use for various indications, umbilical cord blood is considered as an established source of cells with marrow and postmobilization peripheral blood. The limited number of cells still remains a problematic element restricting their use, especially in adults who require to be grafted with a higher cell number. Improving the quality of harvested cord blood, at least in terms of volume and amount of cells, is essential to decrease the number of discarded units. In this review, we examine several variables related to parturient, pregnancy, labor, delivery, collection, the newborn, umbilical cord, and placenta. We aim to understand the biologic mechanisms that can impact cord blood quality. This knowledge will ultimately allow targeting donors, which could provide a rich graft and improve the efficiency of the collection.

Human Umbilical Cord Blood CD45+ Pan-Hematopoietic Cells Induced a Neurotherapeutic Effect in Mice with Traumatic Brain Injury: Immunophenotyping, Comparison of Maternal and Neonatal Parameters, and Immunomodulation

Human umbilical cord blood (HUCB) transplantation has become an alternative cell therapy for hematological and oncological malignancies in the clinic and is considered for neurological disorders. The heterogeneity in the content of the different stem and progenitor cells composing HUCB mononuclear cells (MNC) may influence their engraftment and neurotherapeutic effect. We hypothesized that CD45 pan-hematopoietic marker expression is heterogeneous in MNC, and therefore, CD45⁺ subpopulation enrichment for neurotherapy may provide a tool to overcome cellular variance in different HUCB units. We employed an immunomagnetic separation method to isolate and characterize HUCB CD45⁺ pan-hematopoietic subpopulation and to investigate whether the vaginal or cesarean deliveries influence their neurotherapeutic effect in a traumatic brain injury (TBI) mouse model. Adult C57BL/6J male mice were subjected to moderate TBI and intravenously xenotransplanted with 1 × 10⁶ CD45⁺ cells derived from either vaginal or cesarean HUCB units. A large heterogeneity in the expression of CD45 marker in MNC, both in vaginal and cesarean HUCB units, was found, regardless of the number of live births. A higher expression of hematopoietic markers was found in the CD45⁺ subpopulation while low expressional levels of typical mesenchymal markers were detected. Neurotherapeutic effects, evaluated with an established neurological severity score and novel object recognition test, indicated improved functional motor and memory recovery and found independent of delivery type. Cytokine analysis in extracts of TBI brain cortices indicated an acute immunomodulatory effect by HUCB CD45⁺ subpopulation upon xenotransplantation. These results may provide insights to CD45 marker as a predictor of HUCB units' quality for neurotherapy in TBI.

A new strategy for umbilical cord blood collection developed at the first Colombian public cord blood bank increases total nucleated cell content

BACKGROUND

The total nucleated cell dosage of umbilical cord blood (UCB) is an important factor in determining successful allogeneic hematopoietic stem cell transplantation after a minimum human leukocyte antigen donor-recipient match. The northern South American population is in need of a new-generation cord blood bank that cryopreserves only units with high total nucleated cell content, thereby increasing the likelihood of use. Colombia set up a public cord blood bank in 2014; and, as a result of its research for improving high total nucleated cell content, a new strategy for UCB collection was developed.

STUDY DESIGN AND METHODS

Data from 2933 collected and 759 cryopreserved cord blood units between 2014 and 2015 were analyzed. The correlation of donor and collection variables with cellularity was evaluated. Moreover, blood volume, cell content, CD34+ count, clonogenic capacity, and microbial contamination were assessed comparing the new method, which combines in utero and ex utero techniques, with the conventional strategies.

RESULTS

Multivariate analysis confirmed a correlation between neonatal birth weight and cell content. The new collection method increased total nucleated cell content in approximately 26% and did not alter pre-cryopreservation and post-thaw cell recovery, viability, or clonogenic ability. Furthermore, it showed a remarkably low microbial contamination rate (1.2%).

CONCLUSION

The strategy for UCB collection developed at the first Colombian public cord blood bank increases total nucleated cell content and does not affect unit quality. The existence of this bank is a remarkable breakthrough for Latin-American patients in need of this kind of transplantation.

The effect of maternal and infant factors on cord blood yield

Umbilical cord blood (CB) can be used as an alternative hematopoietic stem cell source for transplantation in hematological malignancy and blood disorders. The success of transplantation is highly related to the levels of total nucleated cell and CD34⁺ cell counts. The evaluation of optimal conditions can decrease the rate of graft rejection due to low cell count and increases the quality of CB units (CBUs) in the blood bank and the success rate of engraftment. To this end, we review the maternal and infant parameters affecting the quality and quantity of CBUs.

Factor predicting total nucleated cell counts in cord blood units

BACKGROUND

Cord blood (CB) stem cells have been used worldwide in transplant medicine to treat various diseases. The efficacy of stem cells in umbilical CB (UCB) can be predicted by the number of total nucleated cells (TNCs). To optimize the clinical use of stem cells in our population, this study addresses several variables affecting the TNC count.

STUDY DESIGN AND METHODS

This observational, cross-sectional study was conducted in a single center from 2012 to 2014. In total, 957 CB units (CBUs) were collected from consented mothers. Data analyses of clinically accepted CBUs were correlated with maternal and infant factors.

RESULTS

Based on the TNC accepted level of banking, 188 CBUs (19.64%) were rejected. Of the 16 maternal and infant variables evaluated, three factors demonstrated a statistically significant predictive value for the accepted TNC level. CB volume was the best predictive factor (p ≤ 0.0001), followed by newborn birth weight (p = 0.025), and the method of delivery (p = 0.002).

CONCLUSIONS

Several maternal, neonatal, and obstetric factors appear to play a major role in predicting an accepted TNC count, which can be used to improve criteria for the donation of stem cells in CBUs.

The circadecadal rhythm of oscillation of umbilical cord blood parameters correlates with geomagnetic activity - An analysis of long-term measurements (1999-2011)

Recently, we have shown that the contents of total nucleated cells (TNCs) and CD34⁺ hematopoietic stem and progenitor cells (CD34⁺ HSPCs) as well as the cord blood volume (CBV) in umbilical cord blood (UCB) show a circadecadal (~10 years) rhythm of oscillation. This observation was based on an analysis of 17,936 cord blood donations collected during 1999-2011. The aim of the present study was to investigate whether this circadecadal rhythm of oscillation in TNCs, CD34⁺ HSPCs and CBV is related to geomagnetic activity. For the analysis, the yearly averages of TNCs, CD34⁺ HSPCs and CBV in UCB were correlated with geomagnetic activity (Dcx index). Our analysis revealed that (i) all three UCB parameters were statistically significantly correlated with the level of geomagnetic activity, (ii) CBV showed a linear correlation with the Dcx index (r = 0.5290), (iii) the number of TNCs and CD34⁺ HSPCs were quadratic inversely correlated with the Dcx index (r = -0.5343 and r = -0.7749, respectively). Furthermore, (iv) CBV and the number of TNCs were not statistically significantly correlated with the number of either modest or intense geomagnetic storms per year, but (v) the number of CD34⁺ HSPCs was statistically significantly correlated with the number of modest (r = 0.9253) as well as intense (r = 0.8683) geomagnetic storms per year. In conclusion, our study suggests that UCB parameters correlate with the state of the geomagnetic field (GMF) modulated by solar activity. Possible biophysical mechanisms underlying this observation, as well as the outcome of these findings, are discussed.

Time related variations in stem cell harvesting of umbilical cord blood

Umbilical cord blood (UCB) contains hematopoietic stem cells and multipotent mesenchymal cells useful for treatment in malignant/nonmalignant hematologic-immunologic diseases and regenerative medicine. Transplantation outcome is correlated with cord blood volume (CBV), number of total nucleated cells (TNC), CD34+ progenitor cells and colony forming units in UCB donations. Several studies have addressed the role of maternal/neonatal factors associated with the hematopoietic reconstruction potential of UCB, including: gestational age, maternal parity, newborn sex and birth weight, placental weight, labor duration and mode of delivery. Few data exist regarding as to how time influences UCB collection and banking patterns. We retrospectively analyzed 17.936 cord blood donations collected from 1999 to 2011 from Tuscany and Apulia Cord Blood Banks. Results from generalized multivariable linear mixed models showed that CBV, TNC and CD34+ cell were associated with known obstetric and neonatal parameters and showed rhythmic patterns in different time domains and frequency ranges. The present findings confirm that volume, total nucleated cells and stem cells of the UCB donations are hallmarked by rhythmic patterns in different time domains and frequency ranges and suggest that temporal rhythms in addition to known obstetric and neonatal parameters influence CBV, TNC and CD34+ cell content in UBC units.

The impact of fetal and maternal physiologic factors on umbilical cord blood quality as a source of stem cells in Egyptian population

BACKGROUND

Umbilical cord blood (UCB) has rapidly become a clinically useful alternative stem cell source. Many variables have been used to evaluate a UCB unit and predict transplant outcomes. The objective of this study was to measure the expression of hematopoietic stem cells in UCB and its relation to certain maternal and neonatal physiologic factors to establish optimum criteria for UCB donor selection.

STUDY DESIGN AND METHODS

Two hundred UCB units were collected from normal uncomplicated vaginal and cesarean deliveries. Total volume was noted and immediately assessed for total nucleated cell (TNC) count and CD34+ cell concentration. Assessment of maternal and neonatal variables such as mode of delivery, placental weight, baby's birthweight, and sex was made.

RESULTS

The volume of the donations ranged from 42.0 to 126 mL, the TNC count ranged from 5 × 10(9) to 28.7 × 10(9) cells/L, and CD34+ cells ranged from 0.03% to 0.62%. There was a significant positive correlation between cord blood volume and cesarean section (p = 0.01) and placental weight (p = 0.02). There was a significant positive correlation with a p value of less than 0.05 between the number of CD34+ cells and UCB volume and TNC. There was no significant difference between the variables and the TNC count.

CONCLUSION

Our study concludes that cord units collected for banking should be obtained by selecting units of larger volumes, of higher TNCs, from female babies with heavy placenta, and from babies delivered via cesarean section.

CD133 allows elaborated discrimination and quantification of haematopoietic progenitor subsets in human haematopoietic stem cell transplants

The success of haematopoietic stem cell (HSC) transplantation largely depends on numbers of transplanted HSCs, which reside in the CD34(+) populations of bone marrow (BM), peripheral blood stem cells (PBSC) and umbilical cord blood (UCB). More specifically HSCs reside in the CD38(low/-) subpopulation, which cannot be objectively discriminated from mature CD34(+)  CD38(+) progenitors. Thus, better marker combinations for the quantification of more primitive haematopoietic stem and progenitor cells in transplants are required. Recently, by combining CD34 and CD133 we could clearly distinguish CD133(+)  CD34(+) multipotent and lympho-myeloid from CD133(low)  CD34(+) erythro-myeloid progenitors in UCB samples. To qualify the assessment of CD133 for routine quality control of adult HSC sources, we analysed the developmental potentials of CD133(+) and CD133(low) subpopulations in BM and PBSC. Similar to UCB, CD133 expression objectively discriminated functionally distinct subpopulations in adult HSC sources. By implementing anti-CD45RA staining, which separates multipotent (CD133(+)  CD34(+)  CD45RA(-) ) from lympho-myeloid (CD133(+)  CD34(+)  CD45RA(+) ) progenitor fractions, UCB was found to contain 2-3 times higher multipotent progenitor frequencies than BM and PBSC. To test for the consistency of CD133 expression, we compared CD133(+)  CD34(+) contents of 128 UCB samples with maternal and obstetrical factors and obtained similar correlations to related studies focusing on CD34(+) cell contents. In conclusion, implementation of anti-CD133 staining into existing routine panels will improve the quality control analyses for HSC transplants.

Cord blood collection and banking from a population with highly diverse geographic origins increase HLA diversity in the registry and do not lower the proportion of validated cord blood units: experience of the Marseille Cord Blood Bank

Several Cord Blood (CB) Bank studies suggested that ethnicity impaired CB unit (CBU) qualification. The Bone Marrow Donors Worldwide registries present an over-representation of unrelated donors (UD) from Northwestern European descent. This raises the question of equality of access to hematopoietic stem cells transplant, especially in the Mediterranean zone, which has taken in many waves of immigration. The aim of our study is to address whether, in the Marseille CB Bank, CBU qualification rate is impaired by geographic origin. The study compared biological characteristics of 106 CBU disqualified for total nucleated cell (TNC) count (dCBU) and 136 qualified CBU in relation to registry enrichment and haplotype origin. A high proportion (>80%) of both dCBU and CBU had at least one non-European haplotype and enrich CB and UD registries to a higher extent than those with two European haplotypes (P<0.001). No difference was observed between TNC count and volume according to geographic origin. Our study shows that diverse Mediterranean origins do not have an impact on the CBU qualification rate. Partnership with Mediterranean birth clinics with highly trained staff is a reasonable option to increase the HLA diversity of CB Bank inventories and to improve the representation of minorities.

Association between maternal and fetal factors and quality of cord blood as a source of stem cells

OBJECTIVES

To comparatively analyze maternal and fetal factors and quality markers of blood samples in a public umbilical cord blood bank.

METHOD

This is a cross-sectional descriptive study that revisited 458 records of donations from September 2009 to March 2013 at the Hemocentro de Santa Catarina. The means of markers were used to define cutoff points for the quality of cord blood.

RESULTS

Most donations came from women with ages between 18 and 29 years (62.8%), gestational age≥40 weeks (55.2%), vaginal delivery (51.3%), primiparous (41.4%), and with male newborns (54.4%) weighing between 3000 and 3499g (41.8%). The volume of the donations ranged from 71.6 to 275.2mL, the total nucleated cell count ranged from 4.77×10(8) to 31.0×10(8) cells and CD34(+) cells ranged from 0.05 to 1.23%. There were statistically significant differences in the volume with respect to gestation age>38 weeks (p-value=0.001), cesarean section (p-value<0.001) and birth weight>3500g (p-value<0.001). The total nucleated cell count was positively affected by cesarean section (p-value=0.022) and birth weight>3500g (p-value<0.001). There was no statistically significant difference between the variables and the percentage of CD34(+) cells.

CONCLUSIONS

Delivery route and birth weight influence the volume of cord blood and the total nucleated cell count. Gestational age influences only the volume of cord blood.

Optimizing donor selection for public cord blood banking: influence of maternal, infant, and collection characteristics on cord blood unit quality

BACKGROUND

Banked unrelated donor umbilical cord blood (CB) has improved access to hematopoietic stem cell transplantation for patients without a suitably matched donor. In a resource-limited environment, ensuring that the public inventory is enriched with high-quality cord blood units (CBUs) addressing the needs of a diverse group of patients is a priority. Identification of donor characteristics correlating with higher CBU quality could guide operational strategies to increase the yield of banked high-quality CBUs.

STUDY DESIGN AND METHODS

Characteristics of 5267 CBUs donated to the Carolinas Cord Blood Bank, a public bank participating in the National Cord Blood Inventory, were retrospectively analyzed. Eligible CBUs, collected by trained personnel, were processed using standard procedures. Routine quality and potency metrics (postprocessing total nucleated cell count [post-TNCC], CD34+, colony-forming units [CFUs]) were correlated with maternal, infant, and collection characteristics.

RESULTS

High-quality CBUs were defined as those with higher post-TNCC (>1.25 × 10(9)) with CD34+ and CFUs in the upper quartile. Factors associated with higher CD34+ or CFU content included a shorter interval from collection to processing (<10 hr), younger gestational age (34-37 weeks; CD34+ and CFUs), Caucasian race, higher birthweight (>3500 g), and larger collection volumes (>80 mL).

CONCLUSIONS

We describe characteristics identifying high-quality CBUs, which can be used to inform strategies for CBU collection for public banks. Efforts should be made to prioritize collections from larger babies born before 38 weeks of gestation. CBUs should be rapidly transported to the processing laboratory. The lower quality of CBUs from non-Caucasian donors highlights the challenges of building a racially diverse public CB inventory.

Assessing the HLA diversity of cord blood units collected from a birth clinic caring for pregnant women in an ethnically diverse metropolitan area

BACKGROUND

New strategies are emerging in cord blood banking where focusing on birth clinics caring for a high number of mothers belonging to ethnic minorities could offer new possibilities for allotransplantation both for patients of European origin and for patients from ethnic minorities or mixed ancestries.

STUDY DESIGN AND METHODS

Marseilles Cord Blood Bank works with one university birth clinic caring for a culturally and sociologically diverse population. Stringent French legal restrictions apply to recording the geographic origin of parents. To circumvent this limitation and evaluate the contribution of newly banked cord blood units (CBUs) to increasing HLA diversity, we applied an algorithm that allows for the determination of parents' putative haplotypes and thus grossly deduce information on their ancestry. Generic resolution HLA-A, HLA-B, and allelic resolution HLA-DRB1 genotyping for 328 CBUs and 2691 unrelated donors (UDs) between January 2009 and May 2012 were performed. Enrichment from international CBU registry with nonreferenced generic HLA-A, HLA-B, and allelic HLA-DRB1 phenotypes was compared between CBUs identified with one or two non-European haplotypes and CBUs identified with two European haplotypes.

RESULTS

Marseilles CBUs display an increased proportion of HLA antigens frequently expressed in African populations compared to UDs. Whereas 93% of 199 CBUs identified with one or two non-European haplotypes enrich international CBU registry, this result is reduced to 42% for the 129 CBUs identified with two European haplotypes.

CONCLUSION

This study supports a new method to assess HLA diversity. However, such an increased of HLA diversity raises questions about frequencies of CBUs released and clinical relevance from their uses.

Cord blood banking activities at a university hospital in northeast Mexico: an 8-year experience

BACKGROUND

Umbilical cord blood (UCB) represents an alternative source of stem cells for transplantation for the treatment of hematologic malignancies and genetic disorders. There is scarce information detailing cord blood bank (CBB) collection and transplantation activities from developing countries. We documented our experience at a public university hospital in northeast Mexico.

STUDY DESIGN AND METHODS

We carried out a retrospective and descriptive analysis of our CBB activity during an 8-year period from May 2002 to September 2010. Collection, processing, and cryopreservation of CB were carried out following standard operating procedures. The minimum volume and total nucleated cell (TNC) content for cryopreservation were 80 mL and 8.0 × 10(8) , respectively.

RESULTS

A total of 1256 UCB units were collected; 428 (34%) were banked and 828 (66%) were discarded. The main reason for exclusion was biologic: low volume and/or low number of TNC accounted for 84% of the total discarded units. Cryopreserved cord blood units (CBUs) had a median volume of 113.8 mL (range, 80-213.2 mL) and 13.0 × 10(8) (range, 8 × 10(8) -36.6 × 10(8) ) TNCs. Cell viability was 99.3% (88-100%). The median CD34+ cell content was 4.0 × 10(6) (0.46 × 10(6) -19.38 × 10(6) ). Sixteen units have been released for transplantation, leading to a utilization rate of 3.7%.

CONCLUSION

CBB demands considerable human and financial resources; it is then essential for centers at developing countries to share their experience, results, and databases to increase the probability of finding matching units for their patients. Efforts to create and maintain CBBs allow to offer this therapeutic option at an affordable cost.

Quality-assessments of characteristics of placental/umbilical cord blood associated with maternal age- and parity-related factor

Umbilical cord blood (CB) has been widely used for unrelated allogeneic stem cell transplantation. It is important to determine the quality of CB units to avoid frequent problem of limited cell yields. However, no practical and/or optimum obstetric factors to predict them are yet available. This study analyzed the relationship between maternal/neonatal obstetric factors and the laboratory parameters of CB units to identify the optimum factors associated with a high yield of total nucleated cells (TNC). Primiparae in their early 30s may be one of the first selection criteria for CB donors to obtain higher yield of TNC.

Effects of obstetric factors and storage temperatures on the yield of endothelial colony forming cells from umbilical cord blood

As umbilical cord blood (UCB) is a rich source of endothelial colony-forming cells (ECFC), our aim was twofold: (1) to examine potential obstetric selection criteria for achieving the highest ECFC yields from UCB units, and (2) to determine whether transient storage temperatures of fresh UCB and cryopreservation of UCB units affected ECFC yield and function. ECFC quality was assessed before and after cryopreservation by their clonogenic proliferative potential. Of the 20 factors examined, placental weight was the only statistically significant obstetric factor that predicted ECFC frequency in UCB. Studies on the effects of storage revealed that transient storage of fresh UCB at 4°C reduced ECFC yield compared with storage at 22°C, while cryopreservation of UCB MNCs significantly reduced ECFC recoveries. To our knowledge, this is the first demonstration that placental weight and temperature of storage prior to processing or culture have significant effects on ECFC frequency in UCB. Our studies further support the evidence that cryopreservation of UCB MNCs compromises ECFC recovery.

Relationship between radiosensitivity of human neonatal hematopoietic stem/progenitor cells and individual maternal/neonatal obstetric factors

Hematopoietic stem/progenitor cells (HSPCs) in placental/umbilical cord blood (CB), which is neonatal peripheral blood, have increasingly been used for hematopoietic stem cell transplantations. It is likely HSPCs are sensitive to extracellular oxidative stresses, such as ionizing radiation and redox-directed chemotherapeutic agents. However, the radiosensitivity of HSPCs and neonatal hematopoietic system remains unclear. This study investigated the potential relationship between the radiosensitivity of HSPCs in CB, which was obtained from singleton and full-term deliveries, and maternal/neonatal obstetric factors. Freshly prepared CB CD34(+) cells exposed to 2 Gy X-irradiation were assayed for hematopoietic progenitor cells such as colony-forming unit-granulocyte-macrophage (CFU-GM), burst-forming unit-erythroid (BFU-E), colony-forming unit-granulocyte-erythroid-macrophage-megakaryocyte (CFU-Mix), and colony-forming unit-megakaryocyte (CFU-Meg). As a result, the neonatal weight, placental weight, CB volume, total low-density (LD) cells, and CD34(+) cells showed mutually significant positive correlations. The CB volume and total LD cells showed a significant reverse correlation with the surviving fraction of CFU-Meg. The surviving fraction of CFU-GM in spring (March-May) was significantly higher than that in autumn (September-November). The surviving fraction of CFU-Meg in the spring was significantly lower than that in the autumn. Male neonates showed a significantly higher surviving fraction of CFU-GM than female neonates. Contrarily, females showed a significantly higher surviving fraction of CFU-Meg than males. The present results suggest that the obstetric factors, such as the season of birth and neonatal gender, influence the radiosensitivity of neonatal hematopoiesis.

Influence of obstetric factors on the yield of mononuclear cells, CD34+ cell count and volume of placental/umbilical cord blood

AIM

Placental/umbilical cord blood (CB) has been used increasingly not only for transplantations, but also in the field of life science research. However, little information is available on the biological characteristics of CB units collected in rural areas because no medical facilities are affiliated with CB banks. Little attention has been paid to the collection of CB units in rural areas compared to CB collected in metropolitan areas. CB is a precious source for life science research due to the recent low birth rate in Japan. Therefore, to efficiently utilize CB units, the purpose of the present study was to investigate the optimum obstetric factors associated with a higher yield of mononuclear/CD34(+) cells per CB unit.

METHODS

CB units were collected at a single hospital (Hirosaki National Hospital). A total of 126 CB units from 105 vaginal deliveries and 21 cesarean section deliveries were available for cell separation within 24 h. Mononuclear low-density (LD) cells were separated using Ficoll-Paque and then processed for CD34(+) cell enrichment using magnetic cell sorting. Associations between the maternal/neonatal factors and the yield of LD/CD34(+) cells were analyzed.

RESULTS

Despite the larger net weight of CB collected from cesarean section deliveries, the total number of LD cells collected from vaginal deliveries was significantly higher than that collected from cesarean section deliveries. The total number of LD cells per CB unit from primigravidae was significantly higher compared with that collected from from multigravidae.

CONCLUSION

CB units from vaginal deliveries of primigravidae may be more favorable because they contain a higher yield of mononuclear cells.

Quality rather than quantity: the cord blood bank dilemma

Growing inventories of cord blood units have facilitated access to umbilical cord cell transplantation for many patients lacking conventional stem cell donors. They are in principle 'off-the-shelf', 'fit-for-use', as well as safe and effective therapy products. Cellular enumeration is used as a surrogate of graft potency, and users rely on the rigorous assessment carried out in banks to avoid poor engraftment after thawing (loss of cells or poor function), when the patient's situation is critical. However, in practice, when units are selected, initially on the basis of HLA matching and cell dose assessment, their absolute quality remains uncertain. Unfortunately, quality-related issues (particularly related to viability) are not uncommon in cord blood transplantation. The reasons for potency failures are diverse, but a lack of thorough validation during critical steps of the process and of appropriate use of quality-control tools for timely detection of problematic units are significant contributors. Moreover, incongruence between different sets of standards and regulations, and lack of common quality systems between banks result in a highly heterogeneous international inventory. Therefore, this complicates the matter for the end user of the product. To ameliorate this situation, it is essential to improve quality at each of the critical manufacturing steps wherein potency can be threatened, thereby creating homogeneous inventories of units with excellent quality and quantity.

Pre-birth selection of umbilical cord blood donors

BACKGROUND

. The fact that only a small percentage of cord blood units (CBU) stored are actually used for transplantation contributes to raising the already high costs of their processing and cryopreservation. The identification of predictors allowing the early identification of suitable CBU would allow a reduction of costs for the collection, storage and characterisation of CBU with insufficient volume or cell numbers. In our bank we have adopted a cut-off value for using CBU of 8 x 10(8) nucleated cells and a volume >or= 60 mL.

MATERIALS AND METHODS

In 365 banked CBU, we evaluated the correlation between neonatal/gestational parameters and laboratory data used to assess their quality.

RESULTS

Biparietal diameter (BPD) and abdominal circumference were significantly and positively correlated with CBU volume (r(2)=0.12, p=0.0011 and r(2)=0.092, p=0.0063, respectively). Receiver operating characteristic (ROC) analysis showed that both parameters can be used to identify CBU with insufficient volume (BPD: area under the curve 0.69, 95% CI=0.57-0.82, p=0.004; abdominal circumference: area under the curve 0.67, 95% CI=0.54-0.79, p<0.01). BPD and head circumference, but not abdominal circumference or femoral length, were positively correlated with white blood cell (WBC) count (r(2)=0.215, p=0.031, and r(2)=0.299, p=0.015, respectively). Abdominal circumference, but not BPD, head circumference or femoral length, was statistically significantly correlated with the number of CD34(+) cells in the CBU. Weight at birth and placental weight were positively correlated with WBC count, blood volume, CD34(+) cell count, total colony-forming units and burst-forming units.

CONCLUSION

. Pre-birth assessment of BPD might allow the selection of donors who would yield CBU of sufficient volume and WBC count and avoid the costs of collecting, transferring, storing and analysing CBU with a high probability of resulting unsuitable for transplantation.

Evaluation of Quality Parameters for Cord Blood Donations

SUMMARY: BACKGROUND: Umbilical cord blood (CB) is widely used for hematopoietic stem cell transplantation and holds promise for the development of innovative medicinal products. In order to find out whether the conditions for collection and storage before processing might have an impact on the quality of CB preparations, viability and the clonogenic potential were assessed. METHODS: CB was collected under field conditions. Flow cytometry was used to determine leukocytes, CD34/CD45+ cells, viability, and nucleated red blood cells (NRBC). Clonogenic activity was determined using isolated mononuclear cells (MNC). RESULTS: Neither plasma citrate concentrations nor storage temperature (within 24 h) affected cell viability or colony formation. After storage for 49-80 h, leukocyte viability declined by about 16% compared to CB stored up to 24 h. In contrast, the clonogenic activity and CD34/CD45+ cell content were not affected. A higher gestational age was associated with a lower yield of clonogenic activity compared to midterm deliveries. NRBC varied widely (median 7.3%; range 0.63-17.3%) without relation to gestational age or colony formation. There was a close correlation between the percentage of viable CD34/CD45+ cells and colony formation (r = 0.77 for CFU-GM; r = 0.75 for CFU-C). CONCLUSIONS: The content of viable CD34/CD45+ cells represents the clonogenic activity of CB preparations. Therefore, determination of viable CD34/CD45+ cells should be generally performed as a routine quality control assay.

Impact of maternal and neonatal factors on CD34+ cell count, total nucleated cells, and volume of cord blood

The engraftment outcome of UCB transplantation is highly dependent on cell number. It would be useful to predict CB cell content using information of donor-related variables before cell processing. In this study, CBs were obtained from 1312 single-birth term deliveries in the Buddhist Tzu Chi Stem Cells Center from January 2001 to June 2006. We evaluated whether maternal factors, such as age and race, have an effect on laboratory parameters of hematopoietic content, including CD34+ cell counts, TNCs, and cord blood volume. We also studied the impact of neonatal factors, such as delivery method, gestational age, sex, birth weight, and birth order on the same parameters. In multivariate analysis, babies delivered via Cesarean section had more CD34+ cells and volume, but lower TNCs. Similar results were found for either babies of shorter gestational age or in male infants. Babies with larger birth weight had higher CD34+ cell volume, and TNC, while mothers with fewer previous live births had CB with more TNCs. Maternal age and race had no effect on these laboratory parameters. To conclude, our results suggest that neonatal factors affect CB cell yields. TNCs tend to be more affected by different variables than CD34+ cell counts and volume. These findings may help in collecting CB efficiently and improve the CB transplantation rate.

Maternal and neonatal factors associated with the high yield of mononuclear low-density/CD34+ cells from placental/umbilical cord blood

Placental/umbilical cord blood (CB) contains nucleated cells and hematopoietic stem/progenitor cells (CD34(+) cells). However it is difficult to predict the number of nucleated/CD34(+) cells in each CB before cell processing. Despite many previous studies from institutes affiliated with CB banks in metropolitan areas, little information is available regarding the characteristics of CB units from other medical facilities. The purpose of the present study was to analyze the maternal/neonatal factors on the yield of cells in CB units. A total of 176 CB units were obtained from single-birth and normal vaginal deliveries. Mononuclear low-density (LD) cells were separated using Ficoll-Paque within 24 hrs after CB collection and then processed for the purification of CD34(+) cells. A multiple linear regression analysis was performed to assess the correlations between the yield of cells and maternal/neonatal factors including maternal age, gravid status, duration of labor, gestational age, neonatal height and weight, cord length, and meconium in the amniotic fluid. The total LD cells per CB unit had a weak positive correlation with the maternal age of primigravidae. The total LD cells per CB unit from the primigravidae aged > or = 25 were significantly higher than those from the primigravidae aged < or = 24. The total CD34(+) cells per CB unit from the 1-gravidae were significantly higher than those from the 2-gravidae and 3-gravidae, respectively among all donors. These results indicate that the CB units from the primigravidae aged > or = 25 are more likely to contain higher yield of LD/CD34(+) cells.

Evaluation of Biological Features of Cord Blood Units Collected With Different Methods After Cesarean Section

INTRODUCTION

Cord blood banks are established worldwide as a result of the increased use of umbilical cord blood (UCB) transplantation. The outcomes of this procedure relate to the cell dose of the UCB unit and the UCB collection. The aim of this study was to evaluate whether the mode of collection influenced the biological features of the UCB units.

MATERIALS AND METHODS

We studied 151 UCB units consecutively collected in the cesarean setting with two different methods: in utero after infant delivery and before delivery of the placenta, and ex utero after delivery of placenta.

RESULTS

Sixty-nine UCB units were collected in utero and 82 ex utero. The two groups were comparable for maternal and obstetric factors. The proportion of banked UCB units was similar in the two groups (38% vs 40%, respectively). No statistically significant differences were observed between the methods of collection in term of volume, white blood cell count, total nucleated cell content, CD34(+) cells, and CFU-GM.

CONCLUSION

This preliminary study showed that the two methods of collection in the cesarean setting were overlapping and valid if performed according to standard operating procedures.

Optimizing Umbilical Cord Blood Collection: Impact of Obstetric Factors Versus Quality of Cord Blood Units

INTRODUCTION

The main limitation factor for wide use of umbilical cord blood units (UCBs) as a source of hematopoietic progenitors for transplantation is cell dose. International standard guidelines recommend 2 x 10(7)/kg as the minimal nucleated cell dose for UCB transplantation for adults and 3.7 x 10(7)/kg for children. Therefore it is important to the optimize donor selection and the collection method so as to achieve high cell doses. In this study our main purpose was to determine whether obstetric factors influence UCBs collected.

STUDY DESIGN

The study involved 304 UCBs collected from January to December 2004. The UCBs were collected after donor selection based on international criteria for cord blood banking. We analyzed UCB biological features such as collected volume, total nucleated cells (TNC), and CD34-positive cells, and obstetric factors.

RESULTS

First, our study showed by multivariate analysis that infant weight was the main factor that influenced biologic features of UCB collected such as total volume (P = .000), TNC (P = .000), CD34 total count (P = .003), and CFU-GM (P = .004). Placental weight > 600 g produced a better volume (P = .007) and increased TNC (P = .056). Gestational age > 39 weeks enhanced CD34% (P = .016). Regarding route of delivery, we found that cesarean section produced higher volume and reduced WBC count compared to vaginal delivery, regarding cord length, it increased TNC (P = .037). And last, we noticed that female infants increased WBC (P = .013) and CD34(+) total count (P = .019) more than male ones.

CONCLUSIONS

Our results confirm that volume and TNC are influenced by several obstetric factors, such as greater infant and placental weight, predicting a better collection.

Mode of Collection Does Not Influence Haematopoietic Content of Umbilical Cord Blood Units from Caesarean Deliveries

BACKGROUND

Collection strategy is the first step for collecting good quality cord blood units. There are two main different techniques for collecting cord blood from the umbilical vein: in the delivery room while the placenta is still in the utero by midwifes and obstetricians, or in an adjacent room after placental delivery by cord blood bank trained personal. Our aim was to evaluate the benefits and disadvantages between the two different cord blood collection strategies in caesarean deliveries.

METHODS

We retrospectively analysed data of cord blood units collected from caesarean deliveries for a 3-year period. Caesarean section was performed with a low uterine transversal incision in all patients according to common obstetrical practice. Cord blood collection was performed before or after placental delivery.

RESULTS

Obstetrical and umbilical cord blood data was obtained from 253 caesarean deliveries. No statistically significant difference was observed for obstetrical variables or cord blood variables except for Hct and platelets.

CONCLUSIONS

We conclude both methods produce comparable TNC, CD34 and CFU counts of cord blood units collected from caesarean sections. Before placental delivery collection avoids the financial investment that generates the presence of cord blood banking personal in the maternity ward.

Alloimmune neonatal neutropenia: can we afford the consequences of a missed diagnosis?

The incidence of alloimmune neonatal neutropenia (ANN) is poorly defined. The reported incidence is less than or equal to 0.1%. This prospective study of unselected pregnancies found an incidence of 0.81% based on results of screening 247 'full term' cord blood samples. Alloimmune neonatal neutropenia occurred more frequently in this population than expected from published historical data. Advances in techniques for antineutrophil antibody screening may have contributed to the higher incidence found in this study. The frequency of ANN supports increased surveillance and confirmatory serological testing in infants with unexplained neutropenia.

Umbilical Cord Stem Cells

Until recently, blood that remained in the umbilical cord and placenta after delivery was routinely discarded. Now that this blood is known to contain both hematopoietic stem cells and pluripotent mesenchymal cells, there has been a substantial increase in the clinical use and research investigation of umbilical cord blood in hematopoietic transplantation and regenerative medicine. Until now, standards for collection and processing were not well established. The debate continues regarding the private banking of autologous blood for "biologic insurance" versus public banking for access by the general population. Obstetricians should support the acquisition of cord units for public banking in their geographic location where cord blood banks have established collection procedures. Issues related to cost, quality control, and the need for ethnic diversity in public banks preclude the universal collection of units from all obstetric deliveries. Directed donation of cord blood should be considered when there is a specific diagnosis of a disease within a family known to be amenable to stem cell transplantation.