Analysis of the turin umbilical cord blood bank registry

Cord blood banks collect units with different HLA alleles and haplotypes to volunteer donor banks: a comparative report from Swiss Blood stem cells

Allogeneic haematopoietic SCT is a standard therapy for many patients with haematological diseases. A major aim of public umbilical cord blood (UCB) banking is to establish an inventory with a large HLA diversity. Few studies have compared HLA diversity between UCB banks and volunteer unrelated donor (VUD) registries and examined whether UCB banks indeed collect more units with rare alleles and haplotypes. This study compares HLA-A/B/DRB1 allele frequencies and inferred A/B/DRB1-haplotypes in 1602 UCB units and 3093 VUD from two centres in distinct recruitment areas in Switzerland. The results show that the frequencies of HLA-DRB1 alleles as well as of the HLA-A/B/DRB1 haplotypes differ between UCB and VUD. Ten DRB1 alleles occurred at a 2- to 12-fold higher relative frequency in UCB than in VUD and 27 rare alleles were identified in UCB. Out of these 27 alleles, 15 were absent in the entire VUD data set of the national registry. This difference in allele frequencies was found only by intermediate/high-resolution typing. Targeted recruitment of UCB units from non-Caucasian donors could further increase HLA allele and haplotype diversity of available donors. Intermediate or high-resolution DNA typing is essential to identify rare alleles or allele groups.

A closed system for the clinical banking of umbilical cord blood

Umbilical cord blood (UCB) is a source of hematopoietic progenitor cells and is used as an alternative to the bone marrow or peripheral blood for treatment of several onco-hematological diseases. Because of the limited number of CD34+ hematopoietic stem cells present in UCB units and of the elevated costs of cryopreservation, it is of paramount importance to select the UCB units that are clinically useful before storage and optimize banking efficiency by designing reliable procedures to process and freeze the selected units. Among the different parameters characterizing UCB, nucleated cell (NC) and CD34+ cell content provides useful criteria to select UCB units since clinical data documented that the infused cell load (both NC and CD34+ cells) plays an important role in the successful outcome of transplants. By evaluating volume, CD34+ cell content, NC total amount, and NC density of 117 UCB units, we found a significant association between CD34+ cell content and NC density and total amount, indicating these parameters as useful to decide UCB clinical utility. Furthermore, we set up a fast procedure to process UCB units for storage. A system for NC separation and volume reduction of UCB samples in a dedicated, germ-free, closed circuit was developed, where plasma and red blood cells (RBC) depletion was obtained by sedimentation in the presence of a 3.5% Polygeline solution. By this separation system, both RBC depletion and high NC and CD34+ cell recoveries were achieved in 60 min, and the yield was comparable to the one obtained by other separation methods. Since Polygeline has been clinically used as a plasma expander and no toxic effects on patients were reported, the protocol can be applied in the large-scale banking of UCB.

Results of the cord blood transplantation (COBLT) study unrelated donor banking program

BACKGROUND

The goals of the Cord Blood Transplantation (COBLT) Study banking program initiated in 1996 were to develop standard operating procedures (SOPs) for cord blood (CB) donor recruitment and banking and to build an ethnically diverse unrelated CB bank to support a transplantation protocol.

STUDY DESIGN AND METHODS

The program included collection centers, three banks, a steering committee, and a medical coordinating center (MCC) that developed and validated SOPs and a Web-based data collection system. External oversight was performed by the National Heart, Lung, and Blood Institute and the MCC.

RESULTS

A total of 34,799 potential donors were screened and 20,710 consented. A total of 17,207 ethnically diverse units were collected between 1998 and 2001. A total of 11,077 (64%) units were cryopreserved and quarantined. Of these, 79 percent met eligibility criteria and were HLA-typed and entered into the search registry. Higher CB volumes and cell counts were obtained from cesarean sections compared to vaginal deliveries. Units from African American persons contained lower cell counts per volume compared to other ethnicities. Birth weight correlated with volume and cell content. External oversight was accomplished through custom reports generated by the data collection system and periodic site visits. During maintenance, a breach in the SOPs was detected during a site visit at one of the banks. These units were designated for future use in nonclinical research.

CONCLUSION

The COBLT Study demonstrated that SOPs and data collection can be implemented in multiple banks coordinated by one MCC. Relationships between donor demographics and CB content may be useful in the development of other CB banking programs.

The impact of intrapartum factors on umbilical cord blood stem cell banking

AIMS

Umbilical cord blood can be used as an alternative source for related and unrelated allogeneic stem cell transplantation. This study was undertaken to determine whether intrapartum factors have an influence on the hematopoietic cell compartment of cord blood.

METHODS

Cord blood samples were obtained from 102 normal full-term deliveries for the banking of stem cells. We analyzed the influence of intrapartum factors on the count of CD34+ cells, total nucleated cells, colony forming units and total volume of collection. Fluorescence-activated cell sorting was used to measure CD34+ cell numbers. Statistical analysis was undertaken using Pearson correlation test and multiple regression analysis.

RESULTS

The higher the infants' birthweight the larger was the volume. A lower arterial umbilical pH and a larger blood volume resulted in an increased number of CD34+ cells. A large blood volume, long duration of labor, lower arterial and venous pH were correlated with more nucleated cells. A higher birthweight, larger blood volume and lower arterial pH resulted in an increased number of colony forming units.

CONCLUSIONS

Some intrapartum factors have an impact on the characteristics of collected cord blood cells. Stress during delivery may influence the number of hematopoetic cells, through altered cytokine production. This knowledge may facilitate the selection of optimal cord blood samples for unrelated banking and the early discarding of suboptimal cord blood samples thus resulting in the saving of costs related to expensive further processing.

Transplantation of porcine umbilical cord matrix cells into the rat brain

Immune rejection of transplanted material is a potential complication of organ donation. In response to tissue transplantation, immune rejection has two components: a host defense directed against the grafted tissue and an immune response from the grafted tissue against the host (graft vs host disease). To treat immune rejection, transplant recipients are typically put on immunosuppression therapy. Complications may arise from immune suppression or from secondary effects of immunosuppression drugs. Our preliminary work indicated that stem cells may be xenotransplanted without immunosuppression therapy. Here, we investigated the survival of pig stem cells derived from umbilical cord mucous connective tissue (UCM) after transplantation into rats. Our data demonstrate that UCM cells survive at least 6 weeks without immune suppression of the host animals after transplantation into either the brain or the periphery. In the first experiment, UCM cells were transplanted into the rat brain and recovered in that tissue 2-6 weeks posttransplantation. At 4 weeks posttransplantation, the UCM cells engrafted into the brain along the injection tract. The cells were small and roughly spherical. The transplanted cells were positively immunostained using a pig-specific antibody for neuronal filament 70 (NF70). In contrast, 6 weeks posttransplantation, about 10% of the UCM cells that were recovered had migrated away from the injection site into the region just ventral to the corpus callosum; these cells also stained positively for NF70. In our second experiment, UCM cells that were engineered to constitutively express enhanced green fluorescent protein (eGFP) were transplanted. These cells were recovered 2-4 weeks after brain transplantation. Engrafted cells expressing eGFP and positively staining for NF70 were recovered. This finding indicates a potential for gene therapy. In the third experiment, to determine whether depositing the graft into the brain protected UCM cells from immune detection/clearance, UCM cells were injected into the tail vein and/or the semitendinosis muscle in a group of animals. UCM cells were recovered from the muscle or within the kidney 3 weeks posttransplantation. In control experiments, rat brains were injected with PKH 26-labeled UCM cells that had been lysed by repeated sonic disruption. One and 2 weeks following injection, no PKH 26-labeled neurons or glia were observed. Taken together, these data indicate that UCM cells can survive xenotransplantation and that a subset of the UCM cells respond to local signals to differentiate along a neural lineage.