The use of cord blood for transfusion purposes: current status

Recycling Apparent Waste Into Biologicals: The Case of Umbilical Cord Blood in Italy and Spain

Most public cord blood banking programs are currently facing financial difficulties due to a progressive decline in the number of cord blood transplants performed worldwide and to a high discard rate of the donated units caused by progressively increasing thresholds of the stem cell dose required to perform safe and effective hemopoietic cord blood transplants. Recycling a proportion of unused cord blood units to prepare novel cord blood components obtained with minimal manipulation (platelets, plasma, red blood cells) and to develop more technologically complex products regulated in the US as Cellular and Gene Therapy Products and in Europe as Advanced Therapy Medicinal Products [e.g. virus-specific T cells (VST), natural killer (NK) cells, induced pluripotent stem cells (iPSCs) is a promising strategy to increase the therapeutic value and reduce the financial deficits of public cord blood banking. Based on encouraging preliminary evidences reported in the literature, additional laboratory studies, large multicenter clinical trials and international regulatory harmonization are necessary to achieve these important goals. This article describes organizational, methodological and regulatory advancements developed in Italy and Spain to promote the clinical use of cord blood platelets, plasma and red blood cells.

Allogeneic cord blood red blood cells: assessing cord blood unit fractionation and validation

BACKGROUND

For neonates and preterm infants, in whom a transfusion dose is low, the use of red blood cells (RBC) from cord blood appears to be feasible. Standardisation of fractionation and identification and assessment of quality control parameters for such RBC are still lacking.

MATERIALS AND METHODS

We describe the process used to obtain RBC from cord blood for transfusion purposes, including quality controls to evaluate fractionation performance and the effects of storage. The cord RBC, to which SAG-M was added, were sampled on the day of fractionation, and 7 and 14 days (end of storage) later in order to measure the complete blood count, biochemical parameters and residual white blood cells. We also assessed microbial contamination.

RESULTS

Data relative to 279 cord blood units were evaluated. The median gestational age at collection was 40 weeks (interquartile range [IQR] 39.1-40.7) and the median volume was 90 mL (IQR 81-103). Units were subjected to automated fractionation with Compomat, and packed RBC were suspended in SAG-M solution. The median volume of the SAG-M-suspended units was 31 mL (IQR 24.0-38.1) and the median haematocrit was 54.2% (IQR 49.4-59.5). The median volume after leukoreduction was 22 mL (IQR 17-28), with the volume decrease being similar in units leukoreduced before (n=75) or after (n=204) storage. The haematocrit of leukoreduced units was higher than that of buffy coat-depleted units. Storage at 2-6 °C for 14 days was accompanied by an increase of potassium levels and percentage of haemolysis. Microbial cultures were positive for 2.9% of the collected units.

DISCUSSION

Fractionation of whole cord blood can provide RBC concentrates with similar baseline characteristics as units from adults. The transfusion dose and quality of the units appear safe and suitable for clinical use in neonates, with a satisfactory haematocrit and residual white blood cell content, despite a very variable collection volume.

Human Umbilical Cord Blood Serum/Plasma: Cytokine Profile and Prospective Application in Regenerative Medicine

The concentrations of cytokines and growth factors in human umbilical cord blood serum and plasma samples were measured by multiplex analysis. It was found that in comparison with peripheral blood serum of adult donors, umbilical cord blood serum and plasma contain significantly higher concentrations of the most studied molecules including IL-4, 5, 6, 7, 10 and 15, MCP-1, SCF, and SDF, as well as growth factors directly involved in the processes of regeneration (G-CSF, HGF, PDGF-BB, and VEGF). Thus, umbilical cord blood plasma and especially serum are a rich source of cytokines and growth factors with anti-inflammatory, anti-apoptotic, and angiogenic effects and can be used in various fields of regenerative medicine.

Safety and efficacy of allogeneic umbilical cord red blood cell transfusion for children with severe anaemia in a Kenyan hospital: an open-label single-arm trial

BACKGROUND

In sub-Saharan Africa, children are frequently admitted with severe anaemia needing an urgent blood transfusion, but blood is often unavailable. When conventional blood supplies are inadequate, allogeneic umbilical cord blood could be a feasible alternative. The aim of this study was to assess the safety and efficacy of cord blood transfusion in children with severe anaemia.

METHODS

Between June 26, 2007, and May 20, 2008, 413 children needing an urgent blood transfusion were admitted to Kilifi District Hospital in Kenya. Of these, 87 children were eligible for our study--ie, younger than 12 years, no signs of critical illness, and haemoglobin 100 g/L or lower (if aged 3 months or younger) or 40 g/L or lower (if older than 3 months). Cord blood was donated at Coast Provincial General Hospital, Mombasa, and screened for transfusion-transmitted infections and bacterial contamination. Red blood cells were stored vertically at 2-6°C to enable sedimentation. After transfusion, children were monitored closely for adverse events and followed up for 28 days. The primary outcome measure was the frequency and nature of adverse reactions associated with the transfusion. Secondary outcomes were the changes in haemoglobin concentrations 24 h and 28 days after transfusion, compared with pretransfusion levels. This trial is registered on ISRCTN.com, number ISRCTN66687527.

FINDINGS

Of the 87 children eligible for the study, cord blood was unavailable for 24, six caregivers declined consent, and two children were withdrawn before transfusion. Therefore, 55 children received umbilical cord red blood cells from 74 donations. Ten (18%) children had ten serious adverse events and 43 (78%) had 94 adverse events; the most frequent adverse events were anaemia (n=14), weight loss (n=12), and vomiting (n=10). An independent expert panel judged none of these adverse events to be probably or certainly caused by the cord blood transfusion (one-sided 97·5% CI 0-6·5). Haemoglobin increased by a median of 26 g/L (IQR 21-31) 24 h after transfusion and by 50 g/L (10-68) a median of 29 days (28-35) after transfusion.

INTERPRETATION

These preliminary data suggest that cord blood could be an important supplementary source of blood for transfusion in children in sub-Saharan Africa. Further studies are needed to compare the safety and efficacy of cord blood with conventional adult-donated blood for transfusions. Challenges associated with cost, infrastructure, and scale up also need investigating.

FUNDING

Wellcome Trust.

Tissue perfusion in neonates undergoing open-heart surgery using autologous umbilical cord blood or donor blood components

BACKGROUND

This study evaluates the hemoglobin-oxygen relationship and tissue perfusion during cardiopulmonary bypass (CPB) in neonates undergoing open-heart surgery using autologous umbilical cord blood or donor blood components.

METHODS

We compared perioperative hematocrit (Hct), fetal hemoglobin (HbF), p(50)O(2), pH, pCO(2), serum lactate, duration of mechanical ventilation and intensive care unit (ICU) length of stay in neonates undergoing open-heart surgery using autologous umbilical cord blood (Group I, N=45) or donor blood components (Group II, N=65). The groups were similar with respect to diagnosis, weight, type of procedure, duration of CPB and duration of myocardial ischemia.

RESULTS

Mean p(50)O(2) was significantly lower in Group I during CPB (19.7 vs. 22.3 mmHg, p=0.004) and at the end of CPB (20.1 vs. 22.8 mmHg, p=0.003). Median peak lactate during CPB was higher in Group I (4.8 vs. 2.2 mmol/l, p<0.001). Carbon dioxide tension was identified as an independent predictor of higher p(50)O(2) during CPB in Group I (β=0.88, p=0.002), but not Group II. Bodyweight, Hct, duration of CPB, pre-CPB lactate level and pCO(2) affected peak lactate level during CPB. Although mean duration of ventilation was longer in Group II (mean 51 vs. 43, p=0.004), the groups experienced similar duration of ICU stay (5.8 vs. 5.9 days, p=0.280).

CONCLUSIONS

Despite the fact that the oxyhemoglobin dissociation curve is shifted leftward in patients who receive autologous umbilical cord blood, tissue oxygen delivery appears to be preserved in neonates who undergo open-heart surgery using autologous umbilical cord blood.

Red blood cell transfusion in newborn infants

Red blood cell transfusion is an important and frequent component of neonatal intensive care. The present position statement addresses the methods and indications for red blood cell transfusion of the newborn, based on a review of the current literature. The most frequent indications for blood transfusion in the newborn are the acute treatment of perinatal hemorrhagic shock and the recurrent correction of anemia of prematurity. Perinatal hemorrhagic shock requires immediate treatment with large quantities of red blood cells; the effects of massive transfusion on other blood components must be considered. Some guidelines are now available from clinical trials investigating transfusion in anemia of prematurity; however, considerable uncertainty remains. There is weak evidence that cognitive impairment may be more severe at follow-up in extremely low birth weight infants transfused at lower hemoglobin thresholds; therefore, these thresholds should be maintained by transfusion therapy. Although the risks of transfusion have declined considerably in recent years, they can be minimized further by carefully restricting neonatal blood sampling.

Osmotic parameters of red blood cells from umbilical cord blood

The transfusion of red blood cells from umbilical cord blood (cord RBCs) is gathering significant interest for the treatment of fetal and neonatal anemia, due to its high content of fetal hemoglobin as well as numerous other potential benefits to fetuses and neonates. However, in order to establish a stable supply of cord RBCs for clinical use, a cryopreservation method must be developed. This, in turn, requires knowledge of the osmotic parameters of cord RBCs. Thus, the objective of this study was to characterize the osmotic parameters of cord RBCs: osmotically inactive fraction (b), hydraulic conductivity (Lp), permeability to cryoprotectant glycerol (Pglycerol), and corresponding Arrhenius activation energies (Ea). For Lp and Pglycerol determination, RBCs were analyzed using a stopped-flow system to monitor osmotically-induced RBC volume changes via intrinsic RBC hemoglobin fluorescence. Lp and Pglycerol were characterized at 4°C, 20°C, and 35°C using Jacobs and Stewart equations with the Ea calculated from the Arrhenius plot. Results indicate that cord RBCs have a larger osmotically inactive fraction compared to adult RBCs. Hydraulic conductivity and osmotic permeability to glycerol of cord RBCs differed compared to those of adult RBCs with the differences dependent on experimental conditions, such as temperature and osmolality. Compared to adult RBCs, cord RBCs had a higher Ea for Lp and a lower Ea for Pglycerol. This information regarding osmotic parameters will be used in future work to develop a protocol for cryopreserving cord RBCs.

Recent advances toward defining the benefits and risks of erythrocyte transfusions in neonates

Like many treatments available to small or ill neonates, erythrocyte transfusions carry both benefits and risks. This review examines recent publications aimed at better defining those benefits and those risks, as means of advancing evidence-based neonatal intensive care unit transfusion practices. Since decisions regarding whether to not to order an erythrocyte transfusion are based, in part, on the neonate's blood haemoglobin concentration, the authors also review recent studies aimed at preventing the haemoglobin from falling to a point where a transfusion is considered.

Comparison of stored umbilical cord blood and adult donor blood: transfusion feasibility

Objective: This study aimed to compare the storage properties of red blood cell (RBC) concentrates of umbilical cordblood (UCB) and adult donor blood (ADB), and to evaluate the feasibility of UCB-RBC concentrate as an autologoussource for blood transfusion in very low birth weight (VLBW) preterm neonates.

Material and Methods: In all, 30 newborn (10 preterm, 20 full term) UCB and 31 ADB units were collected.RBC concentrates were stored and compared with regard to pH, potassium (K⁺), 2,3-biphosphoglycerate (2-3-BPG),adenosine tri-phosphate (ATP), plasma Hb, and bacterial contamination on d 1, 21, and 35 of storage.

Results: The K⁺ level increased with time and differed significantly between storage d 1 and 21, and between storaged 1 and 35 in both the UCB and ADB units. Initial and d 21 K⁺ levels were higher in the UCB units than in the ADBunits. The 2,3-BPG level did not differ significantly between the UCB-PRC and ADB-PRC samples. After 35 d of storageboth UCB-PRC and ADB-PRC samples exhibited significant differences from the initial free Hb, intracellular ATP, andpH values. Significant differences in intracellular ATP and pH were also observed between the UCB-PRC and ADB-PRCsamples.

Conclusion: The volume of harvested and prepared UCB-PRC can be used for some of the blood transfusions requiredduring the neonatal period and thus may decrease the number of allogeneic transfusions, especially in preterm newborns.The hematological and biochemical changes that occurred in UCB during storage were comparable with those observedin ADB, and do not pose a risk to the immature metabolism of neonates. UCB-RPC prepared and stored under standardconditions can be a safe alternative RBC source for transfusions in VLBW newborns.

Arterial switch operation in the first hours of life using autologous umbilical cord blood

BACKGROUND

In this study, we analyzed our clinical experience performing the arterial switch operation in the first hours of life using autologous umbilical cord blood transfusion (AUCBT). The safety and efficiency of AUCBT was assessed and compared with surgery with the use of homologous blood transfusion.

METHODS

Between September 2009 and February 2011, 61 neonates underwent ASO at our institution. Patients were enrolled and allocated to two groups with different modalities of management strategies for neonates with dextrotransposition of the great arteries.

RESULTS

The groups were similar in diagnoses, birth weight, cardiopulmonary bypass protocol, and surgical technique, excepting timing of surgery and blood management strategy. Preoperative mean hematocrit did not differ significantly between the groups (45% versus 45%). Mean hematocrit was significantly lower in the study group than in the control group during cardiopulmonary bypass (24% versus 31%). The hematocrit progressively increased in the study group to 38% on the first postoperative day. Serum lactate levels were higher in the study group till the second day after surgery. There were no significant differences in postoperative clinical profiles. There were no hospital deaths and no AUCBT-related side effects in our study.

CONCLUSIONS

The arterial switch operation can be performed in the first hours of life with AUCBT. Therefore, AUCBT is a safe and an efficient alternative to homologous blood in neonatal open heart surgery. During the study, we also identified positive economic effects associated with this approach.

The microbiologic safety of umbilical cord blood transfusion for children with severe anemia in Mombasa, Kenya

BACKGROUND

Severe anemia requiring blood transfusion is common in hospitalized young children in sub-Saharan Africa but blood is often in short supply. Umbilical cord blood may be a useful source of blood if microbiologic safety concerns can be addressed.

STUDY DESIGN AND METHODS

Cord blood, donated on the labor ward at the provincial hospital in Mombasa, was cultured soon after collection (screening culture) and after a period of storage (poststorage culture). Conventional blood transfused to children at the hospital was cultured only at the time of issue (poststorage culture). Maternal sera (cord blood) and conventional blood donations were also screened for transfusion-transmitted infection.

RESULTS

At poststorage culture, the overall contamination rate of cord blood was one-third that of conventional blood (13/449 vs. 38/434; odds ratio [OR], 0.31; 95% confidence interval [CI], 0.15-0.61) and for bacteria of high pathogenic potential it was half that of conventional blood (4/449 vs. 7/434; OR, 0.55; 95% CI, 0.12-2.18). Screening cultures were positive in 50% (2/4) of cord blood packs where an organism of high pathogenic potential was isolated at poststorage culture. Cord blood donors had a lower seroreactivity than conventional donors for human immunodeficiency virus (OR, 0.63; 95% CI, 0.29-1.18), hepatitis B virus (OR, 0.32; 95% CI, 0.16-0.59), and hepatitis C virus (OR, 0.20; 95% CI, 0.24-0.76). For syphilis, initial seroreactivity in cord blood donors was 3.8% compared to 1.8% in conventional blood donors (OR, 2.10; 95% CI, 1.15-3.60) but was 0.5% after retesting.

CONCLUSION

With respect to bacterial contamination and seroreactivity for transfusion-transmitted infection, the safety of cord blood in Mombasa compares favorably with conventional blood. Clinical trials of cord blood transfusion are justified.

Quality of red blood cells isolated from umbilical cord blood stored at room temperature

Red blood cells (RBCs) from cord blood contain fetal hemoglobin that is predominant in newborns and, therefore, may be more appropriate for neonatal transfusions than currently transfused adult RBCs. Post-collection, cord blood can be stored at room temperature for several days before it is processed for stem cells isolation, with little known about how these conditions affect currently discarded RBCs. The present study examined the effect of the duration cord blood spent at room temperature and other cord blood characteristics on cord RBC quality. RBCs were tested immediately after their isolation from cord blood using a broad panel of quality assays. No significant decrease in cord RBC quality was observed during the first 65 hours of storage at room temperature. The ratio of cord blood to anticoagulant was associated with RBC quality and needs to be optimized in future. This knowledge will assist in future development of cord RBC transfusion product.

[Evolution of neonatal transfusion practices: current recommendations]

Newborns and particularly preterm infants are a population at high risk of transfusion. The implementation of strategies to prevent transfusion by reducing blood loss, use of recombinant human erythropoietin, administration of iron and vitamins and delayed umbilical cord clamping have reduced the frequency of transfusions neonatal periods. The emergence of more stringent recommendations on indications for transfusion has been involved in this development. Various transformations and qualifications for red cell concentrates, platelet concentrates and fresh frozen plasma must be known to better adapt the blood products to newborn term and preterm according to their pathologies. Preparing pediatric units from a single donor for repeated transfusions reduces the allo-immune and infectious risks.

Is there a role for autologous/placental red blood cell transfusions in the anemia of prematurity?

Because most extremely preterm infants with birth weight less than 1000 g need red blood cell transfusions, many attempts have been made to collect, process, and store placental blood (ie, umbilical cord blood) for autologous transfusions. Although it is feasible to do this, multiple problems in doing so including insufficient volumes collected, clotting, hemolysis, bacterial contamination, failure to significantly supplant need for allogeneic transfusions, and high costs have led many to question whether, on balance, autologous/placental red blood cell transfusion offers clinically significant benefits.