Prenatal selection of cord blood donors according to the estimated fetal weight percentile and new approaches; results of a prospective cohort study.

BACKGROUND: Umbilical cord blood (UCB) donation is becoming inefficient and we recently proposed the estimated fetal weight percentile (EFWp) ≥60th as a predictor for a prenatal selection of donors. The aim of this study is to prospectively validate this and to identify new potential prenatal predictive parameters. STUDY DESIGN AND METHODS: Prospective cohort study of low-risk pregnancies undergoing third trimester ultrasound, whose UCB was collected at delivery (2016-2018) and compared with a historical cohort (2013-2016, N = 869). Several ultrasound parameters (EFWp, amniotic fluid, Doppler evaluation, placental thickness) were assessed ultrasound and perinatal data were collected. The association with standard of high quality of UCB was assessed by logistic regression analysis. RESULTS: Among 297 cases, 161 (54%) were selected according to the EFWp ≥60th for UCB units' collection. Cellular criteria for banking was achieved in 27 cases (16.8%), with an average increase of 1.7 times compared to the historical cohort (9.8%, P = .009). Selecting donors according to the 60th EFWp resulted in a higher probability of collecting clinical suitable UCB (P = .025). Among prenatal and perinatal parameters, EFWp, amniotic fluid, umbilical vein (UV) velocity, newborn weight and percentile and placental weight were significantly associated with a higher cellular content. At logistic regression analysis, significant contributors of UCB collection, were EFWp at 37-38 weeks ultrasound (OR 1.04; 95% CI: 1-1.08; P = .042) and UV velocity (OR 1.14; 95% CI: 1-1.29; P = .037). CONCLUSION: The evaluation of the EFWp equal or above 60 and the increased UV velocity can result in higher efficiency of public UCB donation programs.

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.

Determination of Eligibility in Related Pediatric Hematopoietic Cell Donors: Ethical and Clinical Considerations. Recommendations from a Working Group of the Worldwide Network for Blood and Marrow Transplantation Association.

Related donors for hematopoietic cell (HC) transplantation are a growing population in recent years because of expanding indications for allogeneic transplantation. The safety and welfare of the donor are major concerns for the transplantation community, especially for related sibling donors of young recipients who are children and, thus, not able to fully consent. Because donation of HC does not improve the donor's own physical health and carries a risk of side effects, careful assessment of medical risks specific to the individual donor, as well as consideration of ethical and legal aspects associated with donation from a child, must be considered. In addition, donor centers must balance the needs of both the donor and the recipient, understanding the inherent conflict parents may have as they can be overly focused on the very sick child receiving a transplant, rather than on the relatively less significant health or emotional problems that a sibling donor may have, which could impact risk with donation. Likewise, consideration must be made regarding the nature of the relationship of the sibling donor to the recipient and also aspects of performing research on pediatric HC donors. In this article, as members of the Donor Issues Committee of the Worldwide Network for Blood and Marrow Transplantation, we review key ethical concerns associated with pediatric donation and then give recommendations for screening potential child donors with underlying health conditions. These recommendations are aimed at protecting the physical and emotional well-being of childhood donors and arise out of the Third International Conference on Health and Safety of Donors sponsored by the Worldwide Network for Blood and Marrow Transplantation.

Notch signals contribute to preserve the multipotentiality of human CD34(+)CD38(-)CD45RA(-)CD90(+) hematopoietic progenitors by maintaining T cell lineage differentiation potential.

Notch signals are critical for T-cell development, limiting the differentiation potential of multipotent progenitors arriving in the thymus via the bloodstream. Notch ligands Delta-like and Jagged are expressed in the bone marrow and, consequently, a role in the regulation of early events of adult hematopoiesis has been proposed. However, mice with disruptions in the Notch pathway do not show gross defects in the hematopoietic stem cell compartment, limiting Notch effects at later stages of development. In this study, we identify cord blood CD34(+)CD38(-)CD45RA(-)CD90(+) cells, a recently described population of hematopoietic stem cells, as one of the earliest targets of Notch in human hematopoiesis. Upon Notch activation, CD34(+)CD38(-) cells are blocked in their differentiation at the CD34(+)CD38(-)CD45RA(-)CD90(+) stage. Importantly, population and clonal analysis demonstrate that Delta-like-1 exposure does not affect lymphoid vs myeloid decisions. However, Notch signaling is required before lymphoid commitment to preserve T-cell potential of CD34(+)CD38(-)CD45RA(-)CD90(+) cells. Our experiments also show that in terms of differentiation potential, CD34(+)CD38(-)CD45RA(-)CD90(+) cells cultured in the presence of Notch signals, resemble cells directly isolated from cord blood. These results could have implications for translational efforts in the design of strategies aimed to accelerate immune reconstitution after transplantation.

Banking cord blood stem cells: attitude and knowledge of pregnant women in five European countries.

BACKGROUND: This study explores pregnant women's awareness of cord blood stem cells and their attitude regarding banking options in France, Germany, Italy, Spain, and the UK. STUDY DESIGN AND METHODS: Questionnaires were distributed in six maternities. This anonymous and self-completed questionnaire included 29 multiple-choice questions based on: 1) sociodemographic factors, 2) awareness and access to information about cord blood banking, 3) banking option preferences, and 4) donating cord blood units (CBUs) to research. RESULTS: A total of 79% of pregnant women had little awareness of cord blood banking (n = 1620). A total of 58% of women had heard of the therapeutic benefits of cord blood, of which 21% received information from midwives and obstetricians. A total of 89% of respondents would opt to store CBUs. Among them, 76% would choose to donate CBUs to a public bank to benefit any patient in need of a cord blood transplant. Twelve percent would choose a mixed bank, and 12%, a private bank. A total of 92% would donate their child's CBU to research when it is not suitable for transplantation. CONCLUSION: The study reveals a strong preference for public banking in all five countries, based on converging values such as solidarity. Attitudes of pregnant women are not an obstacle to the rapid expansion of allogeneic banking in these EU countries. Banking choices do not appear to be correlated with household income. The extent of commercial marketing of cord blood banks in mass media highlights the importance for obstetric providers to play a central role in raising women's awareness early during their pregnancy with evidence-based medical information about banking options.

Epistasis between HLA-DRB1 parental alleles in a Spanish cohort with multiple sclerosis.

BACKGROUND AND OBJECTIVE: Multiple sclerosis (MS) has been consistently associated with the HLA-DR2 haplotype and particularly with the HLA-DRB1*15 allele. Epistatic interactions between both parental alleles in the DRB1 loci have been shown to modify the MS susceptibility risk. This study investigated the frequencies of various HLA-DRB1 genotypes, their impact on MS susceptibility and their correlation with the clinical severity in a Spanish population. METHODS: A genotype was considered as the combination of the two parental DRB1 alleles. We compared the frequencies of the genotypes in a sporadic MS population (n=380) with those of an unrelated healthy control cohort (n=1088). We correlated the different genotypes with the age at onset, gender distribution, symptoms at onset, course of the disease and progression severity by means of the time to reach the progressive phase and EDSS scores of 3 and 6. RESULTS: We found 81 different genotypes. There were four different MS-predisposing genotypes. Three of them contained the DRB1*15 allele (DRB1*03/15, DRB1*04/15, and DRB1*08/15) and the fourth was homozygote for the DRB1*03 allele. The highest odds ratio was found with the genotype DRB1*08/15 (OR=3.88, 95% CI=1.83-8.26, p<0.01), followed by DRB1*03/03 (OR=3.15, 95% CI=1.93-5.14, p<0.01), DRB1*03/15 (OR=2.72, 95% CI=1.88-3.94, p<0.01) and DRB1*04/15 (OR=2.54, 95% CI=1.64-3.98, p<0.01). The DRB1*01/04 and the DRB1*15/15 genotypes were associated with a shorter time to reach an EDSS score of 6. CONCLUSIONS: Our results show the importance of epistatic interactions among the HLA-DRB1 alleles, modifying the risk for MS as well as its clinical severity.

Basal CD34(+) cell count predicts peripheral blood progenitor cell mobilization and collection in healthy donors after administration of granulocyte colony-stimulating factor.

We analyzed factors predicting CD34(+) cell mobilization and collection after granulocyte colony-stimulating factor (G-CSF) administration in 47 healthy donors. Basal CD34(+) cell count and sex were the two variables that significantly predicted a better CD34(+) cell mobilization, and greater age was the only variable associated with lower CD34+ cell yields.

[Reasons for not carrying out stem cell transplantation in patients referred to a transplant unit]. / Causas por las que no se realiza el trasplante de progenitores hematopoyéticos en pacientes remitidos a una unidad de trasplante.

BACKGROUND AND OBJECTIVE: Although indications of stem cell transplantation (SCT) are increasing, a transplant may not be performed in all planned cases for several reasons. Our objective was to investigate the reasons for which SCT was not performed in patients referred to a transplant unit. PATIENTS AND METHOD: Pretransplant data of 129 patients consecutively referred to a transplant unit between December 1999 and November 2002 were collected. Frequency and causes of non transplantation were analyzed. Transplanted and non transplanted patient's characteristics were compared. RESULTS: In 119 out of 129 patients, an autologous SCT was indicated and in 10 of them an allogeneic SCT was planned. Mean (SD) age was 46 (14) years (range, 13-69) and 69 (53.5%) were males. One hundred eighteen patients had malignant hematological diseases and 11 had solid tumours. Sixty-one patients showed complete response and 68 had a partial response. At the time of the analysis, 93 SCT had been performed in 90 (69.8%) patients. Autologous SCT was performed in 81 patients (two SCT in one patient) and allogeneic SCT in 10 (two in one patient). Two (1.5%) patients were still awaiting SCT. An SCT was not performed in 37 (28.7%) patients. Causes of non transplantation included: in 12 (32.5%) cases, relapse and/or progression at the time the SCT had been planned; in 12 (32.5%), delay or change in the therapeutic decision; in 9 (24%), poor mobilization; and in 4 (11%), patient's refusal. When delay in SCT was excluded from the analysis, the frequency of no transplant was 19.4%. In 21 (57%) patients of the non-SCT group, peripheral stem cells were previously collected by apheresis. Both groups (SCT and non-SCT) were comparable regarding patients' and disease characteristics except for a more advanced age in the non-SCT group (51 [12] vs 44 [14] years, p<0.005) and status of the disease at the pretransplant visit. CONCLUSIONS: The frequency of not performing an SCT in patients referred to a SCT unit was considerable. Relapses and disease progression and poor mobilization were the main causes for it. Delay was also a relatively common cause.

Allogeneic and autologous bone marrow transplantation after consolidation therapy in high-risk acute myeloid leukemia in children. Towards a risk-oriented therapy.

BACKGROUND AND OBJECTIVES: Although chemotherapy in childhood acute myeloid leukemia (AML) has improved in the last decade, except for a group of better-risk patients (approximately one third), more than half the other patients relapse. The main objective of this study was to evaluate the results obtained with bone marrow transplants, either allogeneic (allo-BMT) or autologous (auto-BMT), following two intensive consolidation courses in a series of children with high-risk (HR) AML according to morphologic and early-response BFM criteria. A second objective was to compare the results of auto-BMT with those of allo-BMT. DESIGN AND METHODS: From April 1988 to May 2001, 79 children (< 15 years old) with de novo AML entered the prospective AML-88 trial in a single institution: 50 (63%) were qualified as having high-risk disease and are the subject of this study. After 1 or 2 induction courses, depending on early response, and two consolidations, patients with an HLA-identical sibling received an allo-BMT and all the others an auto-BMT. The conditioning regimen was cyclophosphamide and total body irradiation (TBI) in children over 3 years old and busulfan and etoposide in younger children. Bone marrow was purged with mafosfamide in auto-BMT and cyclosporine alone was given as graft-versus-host disease (GVHD) prophylaxis in allo-BMT. RESULTS: At the end of the chemotherapy phase (induction and consolidation ), 46 of the 50 HR patients (92%) had attained complete remission (CR) after one (n=29), two (n=11) or three (n=6) courses; 2 more were in partial remission (PR) and 2 had died. The 48 patients in CR or PR received either an allo-BMT (17) or an auto-BMT (31). Hematologic reconstitution was significantly slower in auto-BMT recipients. Forty-one percent of patients who received allo-BMT suffered acute GVHD grades II-IV. Toxic deaths and relapse rates were 5.9% and 17.6%, respectively, in allo-BMT and 3.2% and 25.8%, respectively, in auto-BMT. Post-transplant 8-year event-free survival (EFS) was 74.5% (54-96) in allo-BMT and 74.2% (59-89) in auto-BMT. EFS and OS in all the series (50 patients) were 71% (59-83) and 73% (61-85), respectively, with a median follow-up of 7.2 years. INTERPRETATION AND CONCLUSIONS: This study indicates that improved results in children with HR-AML can be obtained by either allo- or auto-BMT performed after two courses of intensive consolidation therapy provided good supportive therapy is given and reduced transplant -related mortality (TRM) is minimized.