Unrelated Umbilical Cord Blood Research Articles

Effects of total body irradiation on hematopoietic cell transplantation outcomes in pediatric acute myeloid leukemia with prior central nervous system involvement

BackgroundThe implications of previous central nervous system (CNS) involvement in children with acute myeloid leukemia (AML) undergoing hematopoietic cell transplantation (HCT) remain inadequately understood. Patients with CNS disease require more upfront CNS directed intrathecal therapy, but little is known about whether transplant conditioning regimens should be intensified or if previous CNS involvement impacts post HCT outcomes. While total body irradiation (TBI) remains standard for pediatric acute lymphoblastic leukemia myeloablative conditioning, it has been largely replaced with chemotherapy-only myeloablation in pediatric AML, primarily due to toxicity and late effects associated with TBI. In the setting of previous CNS involvement, it has been suggested that TBI-based myeloablation may have advantages due to superior CNS tissue penetration and thus decreased rates of AML relapse post HCT. ObjectiveWe analyzed a publicly available dataset derived from the Center of International Blood and Marrow Transplantation Research (CIBMTR) registry to characterize the impact of TBI in HCT preparative regimens in pediatric AML patients with a history of CNS involvement. MethodsThe study dataset was obtained from the CIBMTR data repository. The study cohort included patients aged ≤21 years who underwent initial allogeneic HCT with myeloablative conditioning for de novo AML in the first or second complete remission between 2008 and 2016, who provided consent for research. Patients with mismatched related donor transplant and non-calcineurin inhibitor graft-versus-host disease (GVHD) prophylaxis were excluded. The dataset was further modified by excluding patients with missing disease site data or those with non-CNS extramedullary disease. Patients were categorized as CNS-positive or -negative AML (AML-CNS(+) and AML-CNS(-), respectively) based on the disease status at diagnosis. Cox regression model and Fine Grey methods were employed to delineate the effects of TBI and CNS disease on key HCT outcomes. ResultsThe study cohort comprised 550 pediatric AML patients, of which 25% (n =136) were AML-CNS(+). CNS involvement was more prevalent in patients aged 0-3 years, patients who were in the second complete remission, and those with a mismatched unrelated donor or umbilical cord blood. AML-CNS(+) patients demonstrated a lower relapse rate (hazard ratio [HR]: 0.50, 95% confidence interval: 0.33-0.76) compared to AML-CNS(-) patients, with comparable disease-free survival (DFS) and overall survival (OS) (p =0.10 and 0.20, respectively) in the two cohorts. The entire TBI treated cohort showed an association with increased risks of Grade 2-4 acute GVHD, bloodstream infections, and endocrine dysfunction. TBI use within the AML-CNS(+) cohort was associated with a lower relapse rate but increased risks of non-relapse mortality and a trend of higher grade 3-4 acute GVHD. ConclusionIn this population-based analysis of pediatric patients with de novo AML undergoing HCT, TBI-based conditioning regimens did not confer an advantage in DFS or OS compared to non-TBI regimens, irrespective of CNS disease status. However, TBI use was associated with increased risks of short- and long-term comorbidities. These findings underscore the need for careful consideration of TBI in pediatric AML.

Unrelated umbilical cord blood transplantation with low-dose anti-thymocyte globulin for children with severe aplastic anemia: A case series.

This study aimed to investigate the prognosis of unrelated umbilical cord blood transplantation (UCBT) using low-dose anti-thymocyte globulin (ATG) in children diagnosed with severe aplastic anemia (SAA). This retrospective case series study was conducted involving pediatric SAA patients treated at the Capital Institute of Pediatrics from January 2020 to February 2023. All patients underwent a reduced-intensity conditioning (RIC) regimen alongside low-dose ATG. The study comprised nine patients (five males) with a median age of 5 years (range: 1.7 to 7 years). The median follow-up duration was 799 days (range: 367 to 1481 days), during which all patients survived. The median time interval from diagnosis to transplantation was 3 months (range: 1 to 9 months). The median dosage of ATG administered was 5mg/kg (range: 2.5 to 7.5mg/kg). The median durations for granulocyte and platelet engraftment were 15 days (range: 12 to 23 days) and 26 days (range: 12 to 41 days), respectively. Three patients experienced grade 2-4 acute graft-versus-host disease (aGVHD). Epstein-Barr virus (EBV) reactivation was observed in three patients, while cytomegalovirus (CMV) reactivation occurred in seven patients, with no cases of CMV disease or post-transplant lymphoproliferative disorder (PTLD). One patient experienced recurrence 15 months after transplantation due to influenza A infection. These findings indicate that SAA patients may attain a favorable prognosis following UCBT with a RIC regimen combined with low-dose ATG.

A Randomized, Placebo-Controlled, Phase II Trial of Intravenous Allogeneic Non-HLA Matched, Unrelated Donor, Cord Blood Infusion for Ischemic Stroke.

Stroke remains a leading cause of death and disability in the US, and time-limited reperfusion strategies remain the only approved treatment options. To address this unmet clinical need, we conducted a phase II randomized clinical trial to determine whether intravenous infusion of banked, non-HLA matched unrelated donor umbilical cord blood (UCB) improved functional outcome after stroke. Participants were randomized 2:1 to UCB or placebo within strata of National Institutes of Health Stroke Scale Score (NIHSS) and study center. Study product was infused 3-10 days following index stroke. The primary endpoint was change in modified Rankin Scale (mRS) from baseline to day 90. Key secondary outcomes included functional independence, NIHSS, the Barthel Index, and assessment of adverse events. The trial was terminated early due to slow accrual and logistical concerns associated with the COVID-19 pandemic, and a total of 73 of a planned 100 participants were included in primary analyses. The median (range) of the change in mRS was 1 point (-2, 3) in UCB and 1 point (-1,4) in Placebo (P = 0.72). A shift analysis comparing the mRS at day 90 utilizing proportional odds modeling showed a common odds ratio of 0.9 (95% CI: 0.4, 2.3) after adjustment for baseline NIHSS and randomization strata. The distribution of adverse events was similar between arms. Although this study did not suggest any safety concerns related to UCB in ischemic stroke, we did not show a clinical benefit in the reduced sample size evaluated.

Mismatched Unrelated Donor Transplantation with Ptcy-Based Gvhd Prophylaxis Is Associated with Better Survival Than Double Unit Umbilical Cord Blood Transplantation in Patients with AML in First CR: A Study from the ALWP of the EBMT

Background: The best donor option for acute myeloid leukemia (AML) patients lacking an HLA-matched donor has remained unknown. The recently reported BNT CTN 1101 trial observed higher non-relapse mortality (NRM) and lower overall survival (OS) in patients randomized to double-unit unrelated umbilical cord blood transplantation (dCBT) in comparison to those randomized to HLA-haploidentical bone marrow transplantation with post-transplant cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis 1. In addition, recent registry studies observed at least as good transplantation outcomes in AML patients given grafts from 9/10 HLA-matched unrelated donor (UD 9/10) with PTCy-based GVHD prophylaxis as those given grafts from HLA-haploidentical donors 2,3. These observations prompted us to perform a retrospective registry study comparing hematopoietic cell transplantation (HCT) outcomes between UD 9/10 and dCBT. Methods: Inclusion criteria consisted of adult patient, AML in CR1 at transplantation, either peripheral blood stem cells (PBSC) from UD 9/10 with PTCy as GVHD prophylaxis or dCBT, transplantation between 2013 and 2021, and no in vivo T-cell depletion. Results: A total of 208 dCBT patients and 270 UD 9/10 allo-HCT were included. The 180-day cumulative incidence of grade II-IV acute GVHD was 29% in UD 9/10 versus 44% in dCBT recipients (P=0.001). The 2-year cumulative incidences of relapse and of NRM were 23.5% and 12.5%, respectively, in UD 9/10 recipients versus 27% (P=0.39) and 18% (P=0.07), respectively in dCBT recipients. Two-year OS and LFS were 70% and 64%, respectively, in UD 9/10 recipients versus 60% (P=0.016) and 55% (P=0.028), respectively in dCBT recipients. In multivariate analyses, in comparison with UD 9/10 recipients, dCBT patients had a higher non-relapse mortality (HR=2.35, 95% CI: 1.23-4.48; P=0.01), comparable relapse incidence (HR=1.12, 95% CI: 0.67-1.86; P=0.66), lower leukemia-free survival (HR=1.5, 95% CI: 1.01-2.23; P=0.047), and lower overall survival (HR=1.66, 95% CI: 1.08-2.55; P=0.02). Conclusions: In summary, our results suggest that transplantation outcomes are better with UD 9/10 with PTCy-based GVHD prophylaxis than with dCBT for AML patients in CR1. These data might support the use of UD 9/10 with PTCy-based GVHD prophylaxis in AML patients lacking an HLA-matched donor. References Fuchs, E. J. et al. Double unrelated umbilical cord blood vs HLA-haploidentical bone marrow transplantation: the BMT CTN 1101 trial. Blood 137, 420-428 (2021).Baron, F. et al. Comparison of HLA-mismatched unrelated donor transplantation with post-transplant cyclophosphamide versus HLA-haploidentical transplantation in patients with active acute myeloid leukemia. Bone Marrow Transplant. 57, 1657-1663 (2022).Battipaglia, G. et al. Post-transplant cyclophosphamide in one-antigen mismatched unrelated donor transplantation versus haploidentical transplantation in acute myeloid leukemia: a study from the Acute Leukemia Working Party of the EBMT. Bone Marrow Transplant. 57, 562-571 (2022).

Outcomes and Late Complications after Umbilical Cord Blood Transplantation for Fanconi Anemia: A Study on Behalf of Eurocord and Severe Aplastic Anemia Working Party - EBMT

Fanconi Anemia (FA) remains a disease with poor prognosis for which hematopoïetic cell transplantation (HCT) offers the only available curative option, with particular good results observed after matched sibling donor transplants. This study aimed to assess transplant outcomes and describe late complications in a large cohort of patients with FA who underwent umbilical cord blood transplantation (UCBT) in the European Society for Blood and Marrow Transplantation (EBMT) affiliated centres. Methods: We retrospectively reviewed all cases of FA whoreceived UCBT as first allogeneic transplant between 1988 and 2021. Data on late effects were collected with a questionnaire completed by transplant centres for patients who survived >2 years (y) after UCBT. Results: A total of 205 patients with FA received UCBT (55 related and 150 unrelated) in 77 transplant centres. Indications for UCBT were bone marrow failure in 191 patients (BMF, 93%) and acute leukemia/myelodysplasia in 14 patients (AL/MDS, 7%). Median age at transplant was 8.8 y (1.2-43) and 90% (n=185) were children <18y old. Graft sources included single (n=164), double (n=23) or UCB co-infused with other cell sources (n=18). Recipients and UCB pairs had 0-1/6 HLA mismatches in 48% (n=99). Most patients (n=196, 97%) received reduced intensity conditioning. Flu Cy-based (n=116; 57%) and Bu Cy ± Flu (n=48, 23%) were the most frequently used regimens. Total body irradiation (TBI) or total lymphoid irradiation (TLI) were administered to 28% (n=58) of patients at doses < 8 Gy. Serotherapy consisted of anti-thymocyte globulin (ATG, n=159; 78%) or alemtuzumab (n=8; 4%). Graft- vs-host disease (GVHD) prophylaxis was mainly based on CSA ± steroids (65%) or MMF ± steroids (32%). Median follow-up was 88 months (3-345). The cumulative incidence (CI) of neutrophil recovery was 79% (67-79) at day 60,with a median time of 20 (7-62) days (d). The 100d CI of grades II-IV acute GVHD (aGVHD) was 29.8% (24-37). The 5y CI of chronic GVHD (cGVHD) was 30.4% (24-38) with 12% extensive forms. The 1y-CI of non-relapse mortality (NRM) was 37.4% (31-45). At 5y follow-up, event-free survival (EFS) was54% ± 3 and overall survival (OS) was 55% ± 3. In multivariate analysis, HLA matching 0-1/6 (HR 2.0, p=0.01) and related UCBT (HR 2.4; p=0.001) were predictive of better engraftment. None of the tested factors had statistical significant impact on incidence of aGVHD or cGVHD. Negative recipient CMV serology (HR 0.29, p=0.003) and transplant year ≥2013 (HR 0.29; p=0.004) were the only factors associated with improved OS. Both factors were also predictive of better NRM and EFS. Fifty-one recipients of UCBT (3 related and 48 unrelated) experienced primary graft failure (GF). Twenty-six patients underwent subsequent allogeneic HCT within a median of 1.8 months (0.8 -6.8) after first UCBT. Seven subsequent HCT recipients (1 related bone marrow (BM), 1 related peripheral blood, 1 unrelated BM, and 4 unrelated UCB) were alive at last follow-up. Second neoplasms developed in 8 patients (4%) within a median interval of 9.7 y post-UCBT (3.6-13.5) and included one donor derived-AML and 7 solidtumors (1 skin, 2 upper GI, 4 oral cavity) . A totalof93 patients (45%) died from transplant related toxicity (n=85, including 42 who died after GF), second neoplasms (n=6) or unknown cause (n=2). Survival >2y was observed in 106 patients, but comprehensive data for late transplant complications were available only in 45 long-term survivors. For these 45, median post transplant follow-up was 8.7y (2.7-28.8). Late organ impairments ( table 1) included: endocrine disorders (32%), lung (24%), eyes (20%), kidneys (20%), immune system (18%), liver (16%), musculoskeletal, and bone (16%) diseases. Other dysfunctions involved: oral mucosa (11%), neurologic system (7%), gastrointestinal (4%), genital (13%) and urinary tracts (4%). Cardiovascular complications were rare (1 case of chronic pericarditis). Conclusion: Improved outcomes have been observed in recent years in FA patients receiving unrelated UCBT likely due to improved conditioning regimens, effective post-transplant care and better HLA parity. With longer survival, late multi-organ complications are observed. Identification of risk factors and life-long screening for early management of organ impairments and second neoplasms are mandatory to improve quality of life of transplant survivors and decrease late mortality.

Umbilical Cord Blood Stem Cells As Third-Party Adjuvant Infusion in Human Leukocyte Antigen Antibody-Positive Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Introduction: The presence of human leukocyte antigen (HLA) antibodies, even if not donor-specific antibodies (DSA), is an important risk factor for graft failure (GF) or poor graft function (PGF) in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, there is no ideal strategy for eradicating or descending HLA antibodies in this population. In the present study, we investigated the efficacy and safety of unrelated umbilical cord blood stem cells (CBCs) as a third-party adjuvant infusion in patients with HLA antibodies undergoing allo-HSCT. Methods:Patients undergoing allo-HSCT from July 2017 to June 2021 were enrolled in this study and HLA antibodies were routinely tested before transplantation. Patients were divided into three groups: Group A (patients with positive/weak positive HLA antibodies and with CBCs infusion), Group B (patients with HLA antibodies positive/weak positive without CBCs infusion), and Group C (patients without HLA antibody nor CBCs infusion). Single unrelated CBCs (HLA4/6 or more compatible ) were infused four hours before donor stem cells. The clinical characteristics of the patients and the paired donors were collected. The occurrence of granulocyte and platelet engraftment time, graft-versus-host disease (GVHD), cytomegalovirus (CMV), Epstein-Barr virus (EBV) reactivation, one-year and two-year relapse-free survival (RFS), transplantation-related mortality (TRM), and overall survival (OS) for all three groups of patients were also analyzed in this study. Results:A total of 90 patients were included in this study (17 in group A, 36 in group B, and 37 in group C). The baseline clinical characteristics of the patients were presented in Table 1. No obvious adverse effects were observed in the process of CBCs infusion. All the patients achieved 100% donor chimerism without CBCs engraftment. There were no significant differences in granulocyte and platelet engraftment time between the three groups. Two patients in Group A and C, and 3 patients in Group B developed PGF, respectively. There were no significant differences in the incidence and grades of acute or chronic GVHD among the three groups ( Figure A, B). In the first 3 months after allo-HSCT, the incidence of EBV reactivation was higher in patients in Group B than that in Group A and C, respectively ( Figure C). There were no significant differences in the CMV reactivation between the three groups in the first 3 months after transplantation ( Figure D). Patients in Group A and B both had lower 1-year RFS and higher 1-year TRM, compared with Group C, respectively ( Figure E, F). However, there were no significant statistical differences in 2-year RFS and TRM between the three groups. Although patients in Group A had longer 2-year OS than that in Group B, there were no significant differences between the two groups: Group A vs Group B (76.5% vs 55.6%, P = 0.194), Group B vs Group C (55.6% vs 85.5%, P < 0.05)( Figure G). A multifactorial Cox regression risk model was established to explore the risk factors affecting OS and suggested that patients' pre-transplantation status (with active malignant disease or minimal residual disease positive) and HLA antibodies pre-transplant were the most independent risk factors for OS (HR = 4.380, 95% CI = 1.544-12.427, P<0.05; HR = 0.196, 95% CI = 0.065-0.587, P<0.05). Conclusions: Patients with positive/weak positive HLA antibodies receiving CBCs as a third-party adjunctive infusion were safe, and there was a benefit in the incidence of EBV reactivation compared to such a population without CBCs infusion. The patients with negative HLA antibodies had higher 1-year RFS and lower 1-year TRM than those with positive/weakly positive HLA antibodies regardless CBCs infusion. Due to the small number of included cases, we will expand the sample number to further validate our results in the future.

Haploidentical Cord Blood Transplantation with 8 mg/kg Antithymocyte Globulin as Graft-versus-Host Disease Prophylaxis Compared to Haploidentical Transplantation with 10 mg/kg Antithymocyte Globulin in the Treatment of Acute Leukemia

Clinical outcomes of the transplantation strategy combined with a haploidentical stem cell graft and an unrelated umbilical cord blood unit (haplo-cord HSCT) with low-dose antithymocyte globulin (ATG) as graft-versus-host disease (GVHD) prophylaxis for the treatment of acute leukemia remains unclear. This study aimed to explore the clinical outcomes of haplo-cord HSCT in acute leukemia patients with the GVHD prevention strategy of 8 mg/kg ATG compared with haploidentical transplantation with 10 mg/kg ATG. A total of 130 patients with acute leukemia who underwent allogeneic HSCT between January 2016 and December 2020 were included in this study, including 70 patients who received haploidentical stem cell grafts and unrelated umbilical cord blood units (haplo-cord HSCT) with 8 mg/kg ATG (haplo-cord-ATG8 group) and haploidentical HSCT with 10 mg/kg ATG (haplo-ATG10 group) in 60 patients. Clinical data were collected and analyzed retrospectively. Patients in the haplo-cord-ATG8 group were significantly older compared with the haplo-ATG10 group (P=.000). Haplo-cord HSCT with reduced ATG to 8 mg/kg results in more rapid neutrophil recovery (P=.036). No between-group differences were observed in platelet recovery or the incidences of Epstein-Barr virus viremia, bloodstream infection, or hemorrhagic cystitis. The rate of grade II-IV acute GVHD by day 100 post-transplantation was higher in the haplo-ATG10 group (27.16% versus 11.48%; P=.033), as was the rate of chronic GVHD at 1 year (14.60% versus 3.36%; P=.048). The rate of cytomegalovirus reaction was higher in the haplo-ATG10 group (48.31% versus 26.30%; P=.022). With a median follow-up of 27.4 months for the haplo-cord-ATG8 group and 27.5 months for the haplo-ATG10 group, overall survival (OS) at 2 years was 79.4% versus 62.8% (P=.005), event-free survival (EFS) was 76.3% versus 55.9% (P=.001), the cumulative incidence of relapse was 10.11% versus 25.97% (P=.164), and nonrelapse mortality (NRM) was 14.33% versus 24.43% (P=.0040). Multivariate analysis identified Center for International Blood and Marrow Transplant Research Disease Risk Index was the sole significant predictor of relapse, NRM, OS, and EFS. Haplo-cord HSCT supported by cord blood with 8 mg/kg ATG as GVHD prophylaxis results in better outcomes compared with haplo-HSCT with 10 mg/kg ATG.

Outcome of first or second transplantation using unrelated umbilical cord blood without ATG conditioning regimen for pediatric bone marrow failure disorders

BackgroundUnrelated umbilical cord blood transplantation (UCBT) for bone marrow failure (BMF) disorders using conditioning regimens without Anti-Thymocyte Globulin (ATG) has been used as an alternative transplantation for emerging patients without matched-sibling donors. Experience with this transplant modality in children is limited, especially as a secondary treatment for transplant failure patients. ProcedureWe retrospectively reviewed 17 consecutive bone marrow failure patients who underwent unrelated umbilical cord blood transplantation in our center and received conditioning regimens of Total Body Irradiation (TBI) or Busulfan (BU) + Fludarabine (FLU) + Cyclophosphamide (CY). ResultsAmong the 17 BMF patients, 15 patients were treated with first cord blood transplantation and another 2 with secondary cord blood transplantation because of graft failure after first haploidentical stem cell transplantation at days +38 and +82.All patients engrafted with a median donor cell chimerism of 50 % at days +7 (range, 16 %–99.95 %) and finally rose to 100 % at days +30. Median time to neutrophil engraftment was 19 days (range, 12–30) and time to platelet engraftment was 32 days (range, 18–61). Pre-engraftment syndrome (PES) was found in 16 patients (94.11 %, 16/17). Cumulative incidence of grades II to IV acute GVHD was 58.8 % (95 % CI: 32.7–84.9 %), and 17.6 % (95 % CI: 2.6–37.9 %) of patients developed chronic GVHD. The 3-year overall survival (OS) and failure-free survival (FFS) rates were 92.86 ± 6.88 %. ConclusionUCBT is an effective alternative treatment for bone marrow failure pediatric patients. TBI/BU + FLU + CY regimen ensure a high engraftment rate for unrelated umbilical cord blood transplantation, which overcomes the difficulty of graft failure. Secondary salvage use of cord blood transplantation may still be useful for patients who have failed after other transplantation.

Human Multi-Chimeric Cell (HMCC) Therapy as a Novel Approach for Tolerance Induction in Transplantation

Cellular therapies are regarded as the most promising approach for inducing transplant tolerance without life-long immunosuppression in solid organ and vascularized composite allotransplantation (VCA). Currently, no therapies are achieving this goal. This study introduces a novel Human Multi-Chimeric Cell (HMCC) line created by fusion of umbilical cord blood (UCB) cells, from three unrelated donors as an alternative therapeutic approach to bone marrow transplantation and tolerance induction in solid organ and VCA transplants. We performed eighteen ex vivo polyethylene glycol mediated fusions of human UCB cells from three unrelated donors to create HMCC. Mononuclear cells labeled with PKH26, PKH67, and eFluor™ 670 fluorescent dyes were fused and sorted creating a new population of triple-labeled (PKH26/PKH67/eFluor™ 670) HMCC. The creation of HMCC from three unrelated human UCB donors was confirmed by flow cytometry and confocal microscopy. Genotyping analyses determined the tri-chimeric state of HMCC by presence of parent alleles and selected loci specific for each of three UCB donors. Phenotype characterization confirmed hematopoietic markers distribution, comparable to UCB donors. HMCC maintained viability and displayed a low apoptosis level. The COMET assay revealed absence of genotoxicity, confirming fusion safety. Colony forming units assay showed clonogenic properties of HMCC. This study confirmed the feasibility of HMCC creation from three unrelated human UCB donors and characterized tri-chimeric state, hematopoietic phenotype, viability, safety, and clonogenic properties of HMCC. The created HMCC line, representing genotype characteristics of three unrelated human UCB donors, introduces a novel therapeutic approach for bone marrow, solid organ, and VCA transplants.Graphical

Novel Human Umbilical Di-Chimeric (HUDC) cell therapy for transplantation without life-long immunosuppression.

Cell-based therapies are promising for tolerance induction in bone marrow (BM), solid organs, and vascularized composite allotransplantation (VCA). The toxicity of bone marrow transplantation (BMT) protocols precludes this approach from routine clinical applications. To address this problem, we developed a new therapy of Human Umbilical Di-Chimeric (HUDC) cells for tolerance induction in transplantation. This study established in vitro characterization of the created HUDC cells. We performed sixteen ex vivo polyethylene glycol (PEG)-mediated fusions of human umbilical cord blood (UCB) cells from two unrelated donors. Fusion feasibility was confirmed in vitro by flow cytometry (FC) and confocal microscopy (CM). The HUDC cells' genotype was assessed by lymphocytotoxicity test and short tandem repeat-polymerase chain reaction (STR-PCR) analysis, phenotype by FC, viability by LIVE/DEAD® assay, and apoptosis level by Annexin V staining. We used COMET assay to assess HUDC cells' genotoxicity after the fusion procedure. Clonogenic properties of HUDC cells were evaluated by colony forming unit (CFU) assay. Mixed lymphocyte reaction (MLR) assay assessed immunogenic and tolerogenic properties of HUDC cells. We confirmed the creation of HUDC cells from two unrelated human donors of UCB cells by FC and CM. Human leukocyte antigen (HLA) class I and II typing, and STR-PCR analysis of HUDC cells confirmed the presence of alleles and loci from both unrelated UCB donors (donor chimerism: 49%±8.3%, n=4). FC confirmed the hematopoietic phenotype of HUDC cells. We confirmed high HUDC cells' viability (0.47% of dead cells) and a low apoptosis level of fused HUDC cells (15.9%) compared to positive control of PKH-stained UCB cells (20.4%) before fusion. COMET assay of HUDC cells revealed a lack of DNA damage. CFU assay confirmed clonogenic properties of HUDC cells, and MLR assay revealed a low immunogenicity of HUDC cells. This study confirmed creation of a novel HUDC cell line by ex vivo PEG-mediated fusion of UCB cells from two unrelated donors. The unique concept of creating a HUDC cell line, representing the genotype and phenotype of both, transplant donor and the recipient, introduces a promising approach for tolerance induction in BM, solid organs, and VCA transplantation.

Side Effects After Use of Bedside Thaw Method for Umbilical Cord Blood Stem Cell Allogeneic Transplantations in a Pediatric Cohort: A Single-center Experience.

Several strategies and procedures have been described for thawing umbilical cord blood (UCB) products. The ideal method for each center depends on the resources, staff training, and access to each of these. We retrospectively evaluated the incidence of side effects using the bedside thaw method after unrelated UCB transplantation. For 34 children, patient, donor, graft characteristics, and side effects were identified. In addition, we attempted to identify the risk factors that could be associated with side effects. 68% of patients experienced any adverse reaction. All the reactions were mild and transient events. The most frequent side effects were vomiting, hypertension, hemolytic reactions, and fever. There were more gastrointestinal events with a faster infusion rate. The thawed at the bedside method is a practical, easy, and safe technique for cord blood transplantation in pediatric-patient settings.

Cost-Effectiveness of Unrelated Umbilical Cord Blood Transplantation versus HLA-Haploidentical Related Bone Marrow Transplantation: Evidence from BMT CTN 1101

BMT CTN 1101 was a Phase III randomized controlled trial comparing reduced-intensity conditioning followed by double unrelated umbilical cord blood transplantation (UCBT) versus HLA-haploidentical related donor bone marrow transplantation (haplo-BMT) for patients with high-risk hematologic malignancies. Here we report the results of a parallel cost-effectiveness analysis of these 2 hematopoietic stem cell transplantation (HCT) techniques. In this study, 368 patients were randomized to unrelated UCBT (n=186) or haplo-BMT (n=182). We estimated healthcare utilization and costs using propensity score-matched haplo-BMT recipients from the OptumLabs Data Warehouse for trial participants age <65 years and Medicare claims for participants age ≥65 years. Weibull models were used to estimate 20-year survival. EQ-5D surveys by trial participants were used to estimate quality-adjusted life-years (QALYs). At a 5-year follow-up, survival was 42% for haplo-BMT recipients versus 36% for UCBT recipients (P=.06). Over a 20-year time horizon, haplo-BMT is expected to be more effective (+.63 QALY) and more costly (+$118,953) for persons age <65 years. For those age ≥65 years, haplo-BMT is expected to be more effective and less costly. In one-way uncertainty analyses, for persons age <65, the cost per QALY result was most sensitive to life-years and health state utilities, whereas for those age ≥65, life- years were more influential than costs and health state utilities. Compared to UCBT, haplo-BMT was moderately more cost-effective for patients age <65 years and less costly and more effective for persons age ≥65 years. Haplo-BMT is a fair value choice for commercially insured patients with high-risk leukemia and lymphoma who require HCT. For Medicare enrollees, haplo-BMT is a preferred choice when considering costs and outcomes.

Umbilical Cord Blood Transplantation: Connecting Its Origin to Its Future.

Transplantation of umbilical cord blood (UCB) is an attractive alternative source of hematopoietic stem cells (HSCs). The unique properties of cord blood and its distinct immune tolerance and engraftment kinetics compared to bone marrow (BM) and peripheral blood progenitor cells, permit a wider disparity in human leukocyte antigen levels between a cord blood donor and recipient after an unrelated umbilical cord blood transplant (UCBT). In addition, it is readily available and has a lowered risk of graft-versus-host disease (GvHD), with similar long-term clinical outcomes, compared to BM transplants. However, the relatively low number of cells administered by UCB units, as well as the associated delayed engraftment and immune reconstitution, pose limitations to the wide application of UCBT. Research into several aspects of UCBT has been evaluated, including the ex vivo expansion of cord blood HSCs and the process of fucosylation to enhance engraftment. Additionally, UCB has also been used in the treatment of several neurodegenerative and cardiovascular disorders with varying degrees of success. In this article, we will discuss the biology, clinical indications, and benefits of UCBT in pediatric and adult populations. We will also discuss future directions for the use of cord blood.

Selection strategy for graft source in 2023

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) grafts have expanded from related human leukocyte antigens (HLA)-matched donors to unrelated HLA-matched donors and umbilical cord blood. Either one of these grafts is now available for almost all patients who need allo-HSCT. Furthermore, an allo-HSCT from an HLA one haplo-mismatched donor can be safely performed with cyclophosphamide administration after transplantation. Graft-versus-host disease (GVHD) and graft-versus-leukemia effects are inextricably linked in allo-HSCT, and a transplant with more GVHD-associated complications is not necessarily a worse transplant as a graft selection indicator. Transplants with severe GVHD have fewer relapses, which offset the negative effects. This study presents data to guide graft selection by comparing transplant outcomes from different donor sources. The current position of post-transplant cyclophosphamide haplo from HLA-one haplo mismatched donor is also discussed based on data presented to date.

Hematology 2022—what is complete HLA match in 2022?

Allogeneic hematopoietic cell transplantation (alloHCT) often represents the only curative treatment for various malignant and nonmalignant disorders. Initially, the only suitable donors were considered human leukocyte antigen (HLA)-matched or partially matched relatives. The founding of international unrelated donor and umbilical cord blood registries expanded unrelated donor options and access for patients. In the absence of a matched sibling donor (MSD) with 13% to 51% availability, the current consensus recommends use of a matched unrelated donor (MUD) at HLA-A, B, C, and DRB1 with consideration of matching at HLA-DPB1 and -DQB1. MUD donor availability (donor willing and available to donate) ranges from 29% to 78% with African American patients on the lower end and white non-Hispanic patients with the highest likelihood of a match. Recent studies comparing donor to no-donor treatment options in malignant disease consistently point to substantially better outcomes following alloHCT. In the absence of an MSD or MUD, alternative donor choices turn to haploidentical related (Haplo), mismatched unrelated donor (MMUD), and umbilical cord blood (UCB). Novel strategies for alloHCT, including the use of posttransplant cyclophosphamide-based graft vs host disease prophylaxis, have expanded the safety and effectiveness of transplant procedures across HLA barriers using Haplo and MMUD. The less restrictive matching requirements for UCB transplant are well documented and allow for transplant across multiply mismatched HLA alleles. When all donor options are considered, nearly all patients have an available donor. Here we discuss the likelihood of donor availability, complete HLA match by available donor type, and current controversies warranting future research.

Outcomes of blood and marrow transplantation in children less than 2-years of age

Allogeneic hematopoietic cell transplantation (Allo-HCT) is a curative option for children with various malignant and non-malignant diseases. Most reports studied all age groups amongst children. Herein we analyzed our data in children transplanted at or less than 2-years of age. We reviewed medical charts of 618 patients who underwent 666 transplantation at our center between 1993 and 2015. There were 340 boys and 278 girls. Median age was 0.7 years (range 0.04-2). Stem cell source was bone marrow (BM) in 492 (73.9%), unrelated umbilical cord blood (UCB) in 161 (24.2%) followed by peripheral blood stem cell (PBSC) in 13 (2%) patients. Matched siblings were the most common donors (n=356, 53.5%), followed by unrelated (n=161, 24.2%) with haploidentical family member donors in 29 (4.4%) transplants. Disease groups were categorized as benign hematology (Thalassemia, Fanconi, Aplastic anemia etc.), benign neoplasm (Langerhans cell histiocytosis, Hemophagocytic Lymphohistiocytosis etc.), non-neoplasms (metabolic disorders, immunodeficiency disorders etc.) and Leukemia/lymphomas (myeloid and lymphoid malignancies etc.). Cumulative incidence of acute GvHD (I-IV) was 31.5% (n=210) and grade III-IV GvHD was 8.7% (n=58). At median follow-up of 115.1 months, the cumulative probability of overall survival (OS) at 5 years was 70.0%±1.9%. Our mortality rate was 31.2% (n=193). The five-year OS was significantly better in patients transplanted for benign hematological disorders (P=.001). Patients transplanted using BM/PBSC as source of stem cells fared significantly better compared to those in which CB was used (P<.001). Post-transplant graft failure remains the leading cause requiring further transplants in this age group. In conclusion, the cumulative probability of OS at 5 years was about 70.0% for all with an OS of 61% in our haploidentical recipients. Analyzing our institutional data over time has enabled us to develop tentative strategies to minimize transplant related toxicities in very young children who are candidates for allo-HCT.

Impact of posttransplant cyclophosphamide on the outcome of patients undergoing unrelated single-unit umbilical cord blood transplantation for pediatric acute leukemia

BackgroundUmbilical cord blood transplantation (UCBT) from unrelated donors is one of the successful treatments for acute leukemia in childhood. The most frequent side effect of UCBT is peri-engraftment syndrome (PES), which is directly associated with the greater prevalence of acute and chronic graft-versus-host-disease (aGvHD and cGvHD). In haploidentical stem cell transplantation, posttransplant cyclophosphamide (PTCY) has been demonstrated to be an effective method against GvHD. However, the effects of PTCY as a GvHD prophylactic in UCBT had not been investigated. This study aimed to evaluate the effects of PTCY on the outcomes of UCBT for pediatric acute leukemia.MethodsThis retrospective study included 52 children with acute leukemia who underwent unrelated single-unit UCBT after myeloablative conditioning regimens. The results from the PTCY and non-PTCY groups were compared.ResultsThe incidence of transplantation-related mortality in non-PTCY and PTCY were 5% and 10% (p = 0.525), respectively. The incidence of relapse in non-PTCY and PTCY were 5% and 23% (p = 0.095), respectively. Second complete remission status (CR2) was an independent risk factor for relapse-free survival (hazard ratio = 9.782, p = 0.001). The odds ratio for sepsis or bacteremia incidence was significantly greater in the PTCY group (9.524, p = 0.017). PTCY group had increased rates of cytomegalovirus activity and fungal infection. The incidence of PES, aGvHD, cGvHD, and hemorrhagic cystitis in the PTCY group was lower than that in the non-PTCY group, although it was not significantly different. Additionally, higher doses of PTCY (29 mg/kg and 40 mg/kg) were associated with lower incidences of aGvHD and severe GvHD (65% and 29%, respectively) than lower doses (93% and 57%, respectively). Engraftment time and graft failure incidence were similar across groups.ConclusionThe results support the safety and efficiency of PTCY as part of PES controlling and GvHD prophylaxis in single-unit UCBT for children with acute leukemia. A PTCY dosage of 29 mg/kg to 40 mg/kg appears to be more effective in GvHD prophylaxis for UCBT patients.

Unrelated umbilical cord blood transplantation for children with hereditary leukodystrophy: A retrospective study.

ObjectiveTo analyze the efficiency of unrelated umbilical cord blood transplantation (UCBT) in the treatment of hereditary leukodystrophy following busulfan- and cyclophosphamide-based myeloablative chemotherapy.MethodsA retrospective study was performed in patients with hereditary leukodystrophy who underwent UCBT after myeloablative chemotherapy between April 2015 and March 2020.ResultsThe study cohort included 12 pediatric patients (ten males), nine with cerebral adrenoleukodystrophy (ALD) and three with juvenile globoid cell leukodystrophy (GLD). All received HLA-matched or partially mismatched unrelated UCBT. There were no cases of graft rejection. Median neutrophil engraftment time was 20 days [12–33 days] and median platelet engraftment time was 29 days [14–65 days]. Median follow-up was 36 months [1–86 months], and the overall survival rate for patients with cerebral ALD and juvenile GLD after UCBT was 77.8% (7/9) and 100% (3/3), respectively. In patients with ALD, although lipid profiles (serum very-long-chain fatty acid) were improved post-UCBT, six patients demonstrated worse neurologic function score and performance status post-UCBT, and six patients had higher Loes scores at last follow-up compared with baseline. In patients with juvenile GLD, all patients showed stable neurologic function score and performance status despite the Loes score of one patient increased slightly after transplantation.ConclusionIn patients with cerebral ALD, patients with no or mild neurological symptoms can benefit from UCBT, while UCBT cannot reverse advanced disease. In patients with juvenile GLD, UCBT is safe and contributes to stabilize neurological function.

Unrelated umbilical cord blood can improve the prognosis of haploidentical hematopoietic stem cell transplantation

BackgroundHaploidentical hematopoietic stem cell transplantation (haplo-HSCT) is widely used as a curative treatment strategy for most types of hematological diseases. However, strategies for enhancing the graft versus leukemia (GVL) effect without aggravating the graft versus host disease (GVHD) effect are still being pursued.MethodsA retrospective cohort study was performed to compare the outcomes between combined unrelated umbilical cord blood (UCB-haplo HSCT) and haplo HSCT.ResultsThe results showed that neither acute GVHD (aGVHD) nor chronic GVHD (cGVHD) was increased in the UCB-haplo HSCT group, and the engraftment and infection rates were similar between the two groups. However, overall survival and progression-free survival were significantly improved, while transplantation-related mortality and relapse were significantly decreased in the UCB-haplo HSCT group by both univariate and multivariate analyses.ConclusionOur results indicated that the addition of a UCB unit could improve the prognosis of haplo-HSCT and enhance the GVL effect without increasing the incidence of GVHD.Trial registrationThe cohort study was retrospectively registered at https://www.chictr.org.cn as ChiCTR2100046681.

Abstract 13 A Randomized, Placebo-Controlled, Phase II Trial of Intravenous Allogeneic Umbilical Cord Blood Infusion for Adults with Ischemic Stroke

IntroductionStroke is the fifth leading cause of death in the United States. Tissue plasminogen activator and mechanical thrombectomy are the only effective treatments, but many patients are ineligible for these treatments.ObjectiveThe objective of this study was to determine whether an intravenous infusion of a non-HLA matched, unrelated donor umbilical cord blood (UCB) would improve functional outcomes.MethodsWe conducted a phase II multicenter, randomized (2:1), placebo controlled, double-blinded trial of UCB in adults with acute ischemic stroke. Patients had to have adequate immune function. Cord blood units were selected from U.S. public cord banks based on blood type, race, and cell dose. Study product was infused 3-10 days post stroke. Participants were randomized within strata of National Institutes of Health Stroke Scale Score (NIHSS) (<12 vs ≥12), and study center. The primary endpoint was change in Modified Rankin Scale (mRS) (baseline minus day 90). The study was powered at 80% (odds ratio of 2). Key secondary outcomes included functional independence at day 90 (mRS <2), NIHSS, the Barthel Index, infusion reactions, and adverse events.ResultsSeventy-nine participants were enrolled at 6 centers when the trial was closed early due to slow accrual related to COVID19; 73 participants (47 randomized to UCB) were included in the safety and efficacy analyses. The median (range) of the change in mRS was 1 (–2, 3) in UCB and 1 (–1, 4) in placebo. A shift analysis based on the proportional odds model showed an odds ratio of 0.9 (95% CI: 0.4, 2.3) after adjustment for baseline mRS and randomization strata. No differences were observed on the key secondary outcomes. There were 17 mild infusion reactions (27.6% UCB; 15.4% placebo). The distribution of serious and non-serious adverse events was similar between arms.DiscussionThis study demonstrated the safety of infusing non-HLA matched UCB to adults with acute ischemic stroke. Feasibility and logistics were challenging. The primary efficacy endpoint did not demonstrate benefit in this underpowered sample size. In a secondary ad hoc analysis, a trend of improved functional outcomes at day 90 in recipients of UCB more than 5 days post stroke (Figure 1) could be explored in future trials.Figure 1.Cord blood versus placebo odds ratio by treatment latency (days).