Human Leukocyte Antigen-matched Related Donor Research Articles

New cost-effective human leukocyte antigen testing algorithm for screening of human leukocyte antigen-matched related donor in thalassemia major patient pretransplant workup

Introduction: India has a huge disease burden of thalassemia major with an estimated 40 million carriers and over a million thalassemia major patients. Very few patients are optimally treated, and the standard of care “hematopoietic stem cell transplant” (HSCT) is out of reach for most patients and their families. The cost of HSCT is significant, and a substantial proportion of it goes to human leukocyte antigen (HLA) testing of family members (HLA screening) in hope of getting a matched related donor (MRD) for HSCT. The aim of this study was to establish that a new proposed testing algorithm of HLA typing would be more cost-effective as compared to the conventional HLA screening within MRD families for possible HSCT. Material and Methods: Buccal swab samples of 177 thalassemia patients and their prospective family donors (232) were collected. Using a new HLA testing algorithm, samples were tested for HLA typing in a sequential manner (first HLA-B, then HLA-A, and finally HLA-DR) using the sequence-specific oligonucleotide probe method on the Luminex platform. Results: The new sequential HLA-A, HLA-B, and HLA-DRB1 testing algorithm showed a 49.1% reduction in cost compared to the conventional HLA testing algorithm. Furthermore, 40 patients (22.59%) were found to have HLA-MRD within the family among other samples that were tested. Conclusion: The new HLA testing algorithm proposed in the present study for identifying MRD for HSCT resulted in a substantial reduction in the cost of HSCT workup.

Successful treatment of eltrombopag following immunosuppressive therapy in pediatric aplastic anemia

Immunosuppressive therapy (IST) is the first-line treatment for patients with aplastic anemia (AA) who require blood transfusion when a human leukocyte antigen-matched related donor is unavailable. However, the proportion of patients with AA who are refractory to IST remains high (30%). IST in combination with eltrombopag has been studied in adults, but its efficacy and safety in children have not been established. We present three cases of AA that were initially refractory to IST but improved with additional eltrombopag administration. These patients were successfully managed using this strategy without the use of hematopoietic cell transplantation (HCT). The first patient achieved a complete response within one month after receiving eltrombopag. When the second and third patients were given eltrombopag, they were able to safely reduce the amount of cyclosporin they were given. They avoided blood transfusions, but no measurable response was obtained. The conjunctival icterus was detected and treated using a dose reduction of eltrombopag. Eltrombopag may be effective in children with AA who are refractory to IST, allowing them to avoid blood transfusions and HCT. More cases treated with this strategy are needed to confirm its efficacy and safety for children with AA.

Propensity score matching/reweighting analysis comparing autologous and allogeneic stem cell transplantation for B-lineage acute lymphoblastic leukemia

We compared the outcomes of autologous stem cell transplantation (auto-SCT) with those of allogeneic stem cell transplantation (allo-SCT) from a human leukocyte antigen-matched related donor in patients with Philadelphia chromosome-negative B-lineage acute lymphoblastic leukemia (ALL). Newly diagnosed patients who underwent allo-SCT (n = 486) or auto-SCT (n = 99) after achieving first complete remission (CR) were included. Propensity score matching (PS) and an inverse probability of the treatment weighting (IPTW) analysis were applied to compensate for imbalances in baseline characteristics. The 5years rates of overall survival (OS) among those in the PS-matched cohorts were 57% [95% confidence interval (CI) 46-67%] for those who received allo-SCT and 44% (95% CI 33-54%) for those who received auto-SCT. Multivariable, propensity score-matched, and IPTW analyses all revealed no statistically significant differences in OS between the two groups [hazard ratios (HR) 0.81, 95% CI 0.53-1.27, p = 0.36; HR 0.84, 95% CI 0.40-1.78, p = 0.65; HR 0.71, 95% CI 0.25-2.02, p = 0.53, respectively]. Prospective trials that include autologous transplantation as a treatment option are needed to examine the potential of autologous transplantation.

Comparing cord blood transplantation and matched related donor transplantation in non-remission acute myeloid leukemia.

Cord blood transplantation (CBT) is an alternative donor transplantation method and has the advantages of rapid availability and the possibility of inducing a more potent graft-versus-leukemia effect, leading to a lower relapse rate for patients with non-remission relapse and refractory acute myeloid leukemia (R/R AML). This study aimed to investigate the impact of CBT, compared to human leukocyte antigen-matched related donor transplantation (MRDT). This study included 2451 adult patients with non-remission R/R AML who received CBT (1738 patients) or MRDT (713 patients) between January 2009 and December 2018. Five-year progression-free survival (PFS) and the prognostic impact of CBT were evaluated using a propensity score (PS) matching analysis. After PS matching, the patient characteristics were well balanced between the groups. The five-year PFS was 25.2% (95% confidence interval [CI]: 21.2-29.5%) in the CBT group and 18.1% (95% CI: 14.5-22.0%) in the MRDT group (P = 0.009). The adjusted hazard ratio (HR) was 0.83 (95% CI: 0.69-1.00, P = 0.045); this was due to a more pronounced decrease in the relapse rate (HR: 0.78, 95% CI: 0.69-0.89, P < 0.001) than an increase in the NRM (1.42, 1.15-1.76, P = 0.001). In this population, CBT was associated with a better 5-year PFS than MRDT after allogeneic HSCT.

The role of early natural killer cell adoptive infusion before engraftment in protecting against human herpesvirus-6B encephalitis after naïve T-cell-depleted allogeneic stem cell transplantation.

Naïve T-cell-depleted grafts have been employed as an ex vivo T-cell depletion (TCD) platform to prevent graft-versus-host disease (GvHD) and improve immune reconstitution by providing rapid donor memory T-cell reconstitution after allogenic hematopoietic stem cell transplantation (allo-HSCT). CD45RA- memory T cells confer protection against viruses such as cytomegalovirus, Epstein-Barr virus, and adenovirus; however, reports have shown an unexpectedly high incidence of human herpesvirus (HHV)-6B encephalitis among pediatric allo-HSCT patients. We report the first 18 consecutive allo-HSCT, 16 haplo-HSCT, and two human leukocyte antigen-matched related donors implanted with naïve TCD grafts. All donors were administered three cell products: first, a CD34+ stem cell product; second, a CD45RA+ TCD graft, followed by an adoptive natural killer (NK) cell infusion within 10 days after HSCT. The study's primary endpoint was the incidence of HHV-6B encephalitis. Engraftment was achieved in 94.5% of cases; 2-year overall survival, event-free survival, and GvHD/relapse-free survival were 87.2% (95% CI 78.6-95.8), 67.3% (95% CI 53.1-81.5), and 64% (95% CI 50.5-78.1), respectively. HHV-6B reactivation occurred in 7 of the haplo-HSCT patients, six of who received a cell infusion with an NK/CD4 ratio <2. None of the patients developed encephalitis. In this clinical study, we show that early adoptive NK cell infusion after a 45RA+ TCD allo-HSCT graft is safe and can prevent HHV-6B encephalitis. We recommend infusing adoptive NK cells after allo-HSCT using CD45RA+ TCD grafts.

Combination of Low-Dose, Short-Course Mycophenolate Mofetil With Cyclosporine and Methotrexate for Graft-Versus-Host Disease Prophylaxis in Allogeneic Stem Cell Transplant.

With the standard regimen for graft-versushost disease prophylaxis in allogeneic stem cell transplant with human leukocyte antigen-matched donor, grade II-IV acute graft-versus-host disease occurs in 30% to 50% of sibling and up to 80% of unrelated recipients. Studies with limited patient numbers have shown efficacy and safety of mycophenolate mofetil for graft-versus-host disease prophylaxis. We investigated the effect of low-dose mycophenolate mofetil added to a standardized prophylaxis regimen for graft-versus-host disease in related human leukocyte antigen-matched allogeneic stem cell transplant. In this prospective randomized clinical trial, we compared cyclosporine and methotrexate versus the combination of cyclosporine, methotrexate, and mycophenolate mofetil in all patients who underwent human leukocyte antigencompatible related donor allogeneic stem cell transplant for acute leukemia during 3 years at the Bone Marrow Transplant Unit at Namazi Hospital, Shiraz University of Medical Sciences (Shiraz, Iran). All 134 patients in both groups underwent successful engraftment. Recovery times for neutrophils and platelets were not significantly different between groups (P < .05). Incidence of acute graft-versus-host disease in the cyclosporine, methotrexate, and mycophenolate mofetil group was less than in the cyclosporine and methotrexate group (21.6% vs 40.9%; P = .041). Incidence of grade II-IV acute graftversus-host disease in the mycophenolate mofetil group was 15.2% versus the control group at 33% (P = .045). Our single-center study suggests the combination of mycophenolate mofetil, cyclosporine, and methotrexate is superior to the standard regimen of cyclosporine and methotrexate for graft-versushost disease prophylaxis after human leukocyte antigen-matched related donor allogeneic stem cell transplant.

Relapse and survival after transplantation for complex karyotype acute myeloid leukemia: A report from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation and the University of Texas MD Anderson Cancer Center.

Despite recent advances in allogeneic hematopoietic stem cell transplantation (AHSCT), the outcome of patients who have acute myeloid leukemia (AML) with a complex karyotype (CK) remains poor. The objective of this study was to identify prognostic factors associated with post-transplantation survival in a large cohort of patients with CK AML. In total, data on 1342 consecutively patients who underwent transplantation for CK (≥3 chromosomal abnormalities) AML were provided by the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation and from the University of Texas MD Anderson Cancer Center database were included in the analysis. The median patient age was 52 years. The donors were human leukocyte antigen-matched related donors (N = 749), matched unrelated donors (N = 513), and mismatched unrelated donors (N = 80). Relapse was the main cause of treatment failure. Overall, 51% of patients relapsed, 17.6% died of treatment-related mortality, and 31.3% survived leukemia-free. In multivariate analysis, the factors associated with an increased risk of relapse were age (>40 years; hazard ratio [HR], 1.1 per 10 years; P = .02), secondary AML (HR, 1.35; P = .01), active disease at transplantation (HR, 1.98; P < .001), and deletion/monosomy 5 (HR, 1.5; P < .001); whereas age (HR, 1.15 per 10 years; P < .001), secondary AML (HR, 1.36; P = .001), active disease at transplantation (HR, 1.99; P < .001), deletion/monosomy 5 (HR, 1.24; P = .008), and deletion/monosomy 7 (HR, 1.44; P < .001) predicted for leukemia-free survival. Disease relapse remains the most common cause of treatment failure for patients with CK AML after transplantation. Novel approaches to decrease the relapse rate and improve survival are needed in these patients. Cancer 2018;124:2134-41. © 2018 American Cancer Society.

Twenty-Five Years of Gene Therapy for ADA-SCID: FromBubble Babiesto an Approved Drug

Twenty-five years have passed since first attempts of gene therapy (GT) in children affected by severe combined immunodeficiency (SCID) due to adenosine deaminase (ADA) defect, also known by the general public as bubble babies. ADA-SCID is fatal early in life if untreated. Unconditioned hematopoietic stem cell (HSC) transplant from matched sibling donor represents a curative treatment but is available for few patients. Enzyme replacement therapy can be life-saving, but its chronic use has many drawbacks. This review summarizes the history of ADA-SCID GT over the last 25 years, starting from first pioneering studies in the early 1990s using gamma-retroviral vectors, based on multiple infusions of genetically corrected autologous peripheral blood lymphocytes. HSC represented the ideal target for gene correction to guarantee production of engineered multi-lineage progeny, but it required a decade to achieve therapeutic benefit with this approach. Introduction of low-intensity conditioning represented a crucial step in achieving stable gene-corrected HSC engraftment and therapeutic levels of ADA-expressing cells. Recent clinical trials demonstrated that gamma-retroviral GT for ADA-SCID has a favorable safety profile and is effective in restoring normal purine metabolism and immune functions in patients >13 years after treatment. No abnormal clonal proliferation or leukemia development have been observed in >40 patients treated experimentally in five different centers worldwide. In 2016, the medicinal product Strimvelis™ received marketing approval in Europe for patients affected by ADA-SCID without a suitable human leukocyte antigen-matched related donor. Positive safety and efficacy results have been obtained in GT clinical trials using lentiviral vectors encoding ADA. The results obtained in last 25 years in ADA-SCID GT development fundamentally contributed to improve patients' prognosis, together with earlier diagnosis thanks to newborn screening. These advances open the way to further clinical development of GT as treatment for broader applications, from inherited diseases to cancer.

Good Laboratory Practice Preclinical Safety Studies for GSK2696273 (MLV Vector-Based Ex Vivo Gene Therapy for Adenosine Deaminase Deficiency Severe Combined Immunodeficiency) in NSG Mice.

GSK2696273 (autologous CD34+ cells transduced with retroviral vector that encodes for the human adenosine deaminase [ADA] enzyme) is a gamma-retroviral ex vivo gene therapy of bone marrow-derived CD34+ cells for the treatment of adenosine deaminase deficiency severe combined immunodeficiency (ADA-SCID). ADA-SCID is a severe monogenic disease characterized by immunologic and nonimmunologic symptoms. Bone-marrow transplant from a matched related donor is the treatment of choice, but it is available for only a small proportion of patients. Ex vivo gene therapy of patient bone-marrow CD34+ cells is an alternative treatment. In order to prepare for a marketing authorization application in the European Union, preclinical safety studies in mice were requested by the European Medicines Agency (EMA). A pilot study and a main biodistribution study were performed according to Good Laboratory Practice (GLP) at the San Raffaele Telethon Institute for Gene Therapy test facility. In the main study, human umbilical cord blood (UCB)-derived CD34+ cells were transduced with gamma-retroviral vector used in the production of GSK2696273. Groups of 10 male and 10 female NOD-SCID gamma (NSG) mice were injected intravenously with a single dose of transduced- or mock-transduced UCB CD34+ cells, and they were observed for 4 months. Engraftment and multilineage differentiation of blood cells was observed in the majority of animals in both groups. There was no significant difference in the level of chimerism between the two groups. In the gene therapy group, vector was detectable in lymphohemopoietic and nonlymphohemopoietic tissues, consistent with the presence of gene-modified human hematopoietic donor cells. Given the absence of relevant safety concerns in the data, the nonclinical studies and the clinical experience with GSK2696273 supported a successful application for market authorization in the European Union for the treatment of ADA-SCID patients, for whom no suitable human leukocyte antigen-matched related donor is available.

Costs of allogeneic hematopoietic cell transplantation using reduced intensity conditioning regimens.

Reduced intensity conditioning (RIC) regimens have allowed older patients and those with comorbidities to receive hematopoietic cell transplantation (HCT). We analyzed medical costs from the beginning of conditioning to 100 days after HCT for 484 patients and up to 2 years for 311 patients who underwent a RIC HCT at two institutions from January 2008 to December 2010. Multiple linear regression was used to analyze the association between clinical variables, center effect, and costs. Patient and transplant characteristics were comparable between the sites, although differences were seen in pretransplant performance scores. Significant predictors for lower costs for the first 100 days included a diagnosis of lymphoma/myeloma and use of human leukocyte antigen-matched related donors. Grade II-IV acute graft-versus-host disease (GVHD) was associated with higher costs. The overall short-term costs between the two institutions were comparable when adjusted for clinical variables (p = .43). Late costs between 100 days and 2 years after HCT were available for one cohort (n = 311); median costs during this period were $39,000 and accounted for 39% of costs during the first 2 years. Late costs were not associated with any pretransplant variables, but were higher with extensive chronic GVHD and death. After adjustment for clinical characteristics, the overall costs of the RIC transplants were similar between the two institutions despite different management approaches (inpatient vs. outpatient conditioning) and accounting methodologies. Use of unrelated/alternative donors, transplant for diseases other than lymphoma or myeloma, and acute GVHD were predictors for higher early costs, and extensive chronic GVHD and death were associated with higher late costs.

Isolated Myeloid Sarcoma of the Vulva

Myeloid sarcoma can involve any anatomic site, but involvement of the gynecologic tract is uncommon. In particular, vulvar myeloid sarcoma is extremely rare, with only 1 case report in the English-language medical literature. A 21-year-old, normally developed Japanese woman presented with a hard, gradually growing mass that involved the patient's right labia majora and whole right vulva. The mass was resected and histologically diagnosed as vulvar myeloid sarcoma, poorly differentiated type on the basis of the immunohistochemical studies. She had no history or simultaneous involvement of any other myeloid neoplasm. The patient had a complete remission (CR) after induction chemotherapy with cytarabine and daunorubicin, and she received another course of the same combination chemotherapy as a consolidation therapy and an allogeneic hematopoietic stem cell transplantation from an human leukocyte antigen-matched related donor. But a first medullar relapse of acute myeloid leukemia (AML) developed, and she needed salvage chemotherapy with daunomycin and cytarabine. She achieved a second CR after the salvage therapy and received a second allogeneic hematopoietic stem cell transplantation from the same donor. However, AML relapsed again and she received reinduction chemotherapy, which consisted of behenoyl cytarabine and aclarubicin, which resulted in a third remission of AML. Three years after the initial resection, the patient is alive, without any evidence of recurrent extramedullary disease. To the best of our knowledge, this is the second report of the vulvar myeloid sarcoma in the English-language medical literature. The correct diagnosis of myeloid sarcoma particularly on an isolated mass is important so that appropriate therapy can be instituted.

Reduced-intensity conditioning with Fludarabin, oral Busulfan, and thymoglobulin allows long-term disease control and low transplant-related mortality in patients with hematological malignancies

The development of reduced-intensity conditioning regimens rather than myeloablative regimens for allogeneic stem cell transplantation has led to decreased treatment-related mortality and increased use of this treatment modality, especially in older patients with hematological malignancies. No randomized controlled trials have been performed resulting in determining effectiveness on phase II studies, which rarely report on long-term survival. In an attempt to address this limitation, we analyzed a single-center cohort of 100 consecutive patients with hematological malignancies undergoing allogeneic stem cell transplantation from a human leukocyte antigen-matched related donor with median follow-up of 60 months. The reduced-intensity conditioning regimen consisted of oral Busulfan, rabbit anti-thymocyte globulin, and Fludarabin. Median age was 50 years (range, 18-64 years). The incidences of acute and chronic graft-vs.-host disease were 43% and 81%, respectively. The probability of nonrelapse mortality at 1 and 5 years was 15% and 25%, respectively. Nonrelapse mortality was adversely associated with acute graft-vs.-host disease (hazard ratio = 6; p = 0.0002). Of the 52 patients with measurable disease, 37 (71%) achieved a response. Relapse/progression occurred at a median of 11 months (range 1-52 months) in 21 patients, for a cumulative incidence of 22%. The probability of overall survival and progression-free survival at 5 years were 60% and 54%, respectively. Overall survival and progression-free survival were favorably influenced by having had previous autologous stem cell transplantation and a low CD34(+) cell dose. Overall survival, progression-free survival, and nonrelapse mortality improved over time in this cohort of patients. These results are encouraging for populations different in term of age, diagnosis, and disease status.

Bone marrow transplantation in children with severe aplastic anemia using a conditioning regimen containing 3 Gy of total body irradiation, cyclophosphamide with or without antithymocyte globulin

We have employed the 3 Gy total body irradiation (TBI) containing conditioning regimen to bone marrow transplantation (BMT) for severe aplastic anemia (SAA) in pediatric patients irrespective of donor type since March 1986. The outcome of BMT for 17 SAA patients is favorable. Eight patients received BMT from human leukocyte antigen matched-related donors (MRD) and nine received BMT from alternative donors. The conditioning regimen consisted of 3-Gy TBI and cyclophosphamide of 200 mg/kg in the BMT from MRD. In the case of BMT from alternative donor, antithymocyte globulin 10 mg/kg was added to the regimen. Fifteen of 17 patients (88%) engrafted on median of day 18 (range, 11-26) and all 13 evaluable patients showed complete donor chimerism by median 30 (range, 13-47) days after BMT. Fourteen patients have survived with a median follow-up of 67 (range, 2-228) months and the probability of survival was 81.9% (95% CI, 63.3-100%). No late complications including second malignancies caused by TBI have been observed and all three female patients have regular menstruation. In conclusion, TBI of 3 Gy appears to be an appropriate dose regarding to ensure engraftment and avoid the risk of late adverse event for SAA patients.

Allogeneic Bone Marrow Transplantation at Wilford Hall U.S. Air Force Medical Center: 1987–1999

Wilford Hall Medical Center (WHMC), at Lackland Air Force Base in San Antonio, Texas, is the only center within the U.S. Department of Defense at which allogeneic bone marrow transplantation (BMT) is performed. From the inception of the BMT program in 1987 through February 1999, 286 military health care beneficiaries have undergone human leukocyte antigen-matched related donor allogeneic bone marrow transplantation for hematologic disorders. We conducted a retrospective chart review to analyze the outcomes of all allogeneic BMT procedures performed at WHMC through February 1999. Our analysis revealed that allogeneic BMT outcomes compared favorably with those reported by the International Bone Marrow Transplant Registry. The results of this study support the continued designation of the Fisher Bone Marrow Transplant Center at WHMC as a specialty treatment service within the Department of Defense.

Controlled trial of filgrastim for acceleration of neutrophil recovery after allogeneic blood stem cell transplantation from human leukocyte antigen–matched related donors

The rapid recovery of hematopoiesis after allogeneic blood stem cell transplantation has been attributed to the quality and quantity of hematopoietic progenitors in the blood stem cell grafts from filgrastim-stimulated donors. To determine whether further stimulation with filgrastim after transplantation would affect hematopoietic recovery, a prospective, randomized, controlled study was performed. Forty-two adult recipients of allogeneic blood stem cells from human leukocyte antigen-matched related donors were randomized to receive 10 microg/kg per day filgrastim subcutaneously from day 1 through neutrophil recovery or no growth factor support after transplantation. There was no significant difference between the 2 groups in the number of CD34(+) cells infused (median, 4.8 vs 4.3 x 10(6)/kg). Graft-versus-host (GVHD) disease prophylaxis consisted of tacrolimus and steroids for 9 patients and tacrolimus and minimethotrexate for 33 patients. The group receiving filgrastim had a shorter time to neutrophil levels greater than 0.5 x 10(9)/L (day 12 vs day 15, P =.002) and to neutrophil levels greater than 1.0 x 10(9)/L (day 12 vs day 16, P =.01). The filgrastim group also had a trend for earlier discharge (day 16 vs 20, P =.05). There was no significant difference between the groups in time to platelet recovery, number of transfusions, regimen-related toxicity, infection, incidence of GVHD, relapse, survival, or hospital charges. It can be concluded that the administration of filgrastim after allogeneic blood stem cell transplantation shortens the time to neutrophil recovery. (Blood. 2001;97:3405-3410)