Sibling Hematopoietic Stem Cell Transplantation Research Articles

The effect of killer cell immunoglobulin-like receptor genotype on outcome of hematopoietic stem cell transplantation from matched sibling

The alloreactivity of natural killer (NK) cell after allogeneic hematopoietic stem cell transplantation (AHSCT) is regulated by the interaction between donor killer immunoglobulin-like receptors (KIRs) and recipient human leukocyte antigen (HLA)-class I molecules. The aim was to identify KIR genes, haplotypes and their HLA-class I ligands and to investigate their association with transplantation outcome. The study included 65 patient/donor pairs who received AHSCT from HLA-matched identical siblings. KIR genotyping was done for donors using reverse sequence specific oligonucleotide probes (rSSO) coupled with luminex technology, while HLA-C genotyping was performed in patients using rSSO strip assay. In multivariate analysis, KIR2DS4 was associated with significant reduced incidence of relapse (p = .002). A trend towards reduced incidence of relapse was also observed with more than two KIR B motifs (p = .09), whereas a significant increased relapse was associated with homozygous HLA-C2 ligand compared to combined C1/C2 and C1/C1 (p = .04). Activating KIR2DS3 was associated with rapid leukocyte engraftment (p = .02). While, KIR 2DL5 was associated with decreased CMV infection (p = .03) and better platelets engraftment (p = .05). KIR genes, haplotypes and HLA-C alleles have an impact on HSCT outcome. Better selection of donors with favorable KIR genotype can improve HLA-matched sibling HSCT outcome especially for AML patients.

Young Female Donors Do Not Increase the Risk of Graft-versus-Host Disease or Impact Overall Outcomes in Pediatric HLA-Matched Sibling Hematopoietic Stem Cell Transplantation

Optimal donor selection is critical in hematopoietic stem cell transplantation (HSCT). Donor–recipient sex mismatch, donor age, and female donor–donor parity are known to impact graft-versus-host disease (GVHD) and outcomes in adults. Minor histocompatibility antigens encoded by the human Y chromosome can result in specific antibody formation in some female donors, may increase in frequency with increasing donor age, and may be contributory to the increased incidence of GVHD. To better understand the role of donor age/sex and sex matching in HSCT outcomes, we conducted a retrospective study of pediatric patients receiving their first myeloablative sibling donor HSCT (n = 244) from 1998 to 2012. Observed rates of GVHD were low: 17% of patients surviving past engraftment (n = 243) developed grades II to IV acute GVHD (aGVHD) and 14% surviving ≥ 100 days (n = 229) developed chronic GVHD (cGVHD). On multivariate analysis the risk of aGVHD, cGVHD, and death increased with patient age as expected. Female donor sex and sex mismatch (female donor–male recipient) had no impact on the development of aGVHD. cGVHD was increased with female donors only if the donor was ≥12 years old. No cGVHD was observed among 109 patients aged < 10 years who received a 6/6 HLA-matched marrow HSCT, regardless of donor age or sex. Survival was mostly driven by diagnosis. Results suggest that in pediatric HSCT, young HLA-matched siblings are equivalently good donors regardless of sex or donor–recipient sex mismatch.

OR8 Killer cell immunoglobulin-like receptor genotype BX1 and centromeric gene-content motifs influences survival after 3-models of allogeneic hematopoietic stem cell transplantation

Aim To investigate the role of donor killer cell immunoglobulin-like receptor (KIR) in allogeneic hematopoietic stem cell transplantation (allo-HSCT) and to develop a donor selection strategy for Chinese population. Methods In this 5-year retrospective study, we performed KIR genotyping on a total of 626 donor and recipient pairs by PCR-SSP. All patients underwent HSCT, comprising 219 HLA-identical sibling HSCT, 210 HLA-identical unrelated donor (URD) HSCT, and 197 HLA haplo-identical HSCT, for treatment of myeloid and lymphoid leukemia. Results Donor KIR genotypes and KIR gene motifs influenced transplantation outcomes for AML/MDS but not ALL/NHL patients in 3 models of transplants. In sibling HSCT for AML/MDS patients (n = 128), KIR mismatch between patient and donor had a better overall survival (OS; 87.3% versus 69.3%; P = 0.027) and reduced grade III to IV acute graft-versus-host disease (aGVHD; 4.6% versus 13.6%; P = 0.029). However, the effect was not observed in URD (n = 122) and haplo-identical HSCT (n = 108) for AML/MDS patients. Multivariate analysis indicated that centromeric B motifs contributed to improved survival in all models of transplants: (1) In sibling HSCT, donors’ haplotype cB-tA/tB were associated with improved OS compared with cA-tB (96.6% versus 71.2%; P = 0.021) or cA-tA (96.6% versus 72.1%; P = 0.017); (2) In URD-HSCT, donors with Cen -B were associated with a significantly improved OS (HR = 0.256; 95% CI, 0.084 to 0.774; P = 0.016) and RFS (HR = 0.252; 95% CI, 0.084 to 0.758; P = 0.014); (3) In haplo-identical HSCT, the same effect of Cen -B was observed on OS (HR, 0.335; 95% CI, 0.164 to 0.667; P = 0.002), RFS (HR, 0.331; 95% CI, 0.167 to 0.657; P = 0.002), and NRM (HR, 0.286; 95% CI, 0.120 to 0.683; P = 0.005). Regarding the KIR genotypes, compared with other donor KIR B/x genotypes: (1) In sibling HSCT, genotype Bx1 was a risk factor for lower OS (HR, 8.667; 95% CI, 2.321 to 32.37; P = 0.001) and RFS (HR, 9.207; 95% CI, 2.631 to 32.22; P = 0.001); (2) The same negative effect of Bx1 was also found in URD-HSCT (OS: P = 0.047; RFS: P = 0.041) and haplo-identical HSCT (OS: P = 0.002; RFS: P = 0.002). Conclusions Avoiding the selection of Bx1 donors is strongly advisable for AML/MDS patients undergoing both related and unrelated HSCT whereas the presence of the Cen -B motifs was rather recommended in donor selection.

Allogeneic stem cell transplantation in patients with atypical chronic myeloid leukaemia: a retrospective study from the Chronic Malignancies Working Party of the European Society for Blood and Marrow Transplantation.

Atypical chronic myeloid leukaemia (aCML) is an aggressive malignancy for which allogeneic haematopoietic stem cell transplantation (allo-HSCT) represents the only curative option. We describe transplant outcomes in 42 patients reported to the European Society for Blood and Marrow Transplantation (EBMT) registry who underwent allo-HSCT for aCML between 1997 and 2006. Median age was 46years. Median time from diagnosis to transplant was 7months. Disease status was first chronic phase in 69%. Donors were human leucocyte antigen (HLA)-identical siblings in 64% and matched unrelated (MUD) in 36%. A reduced intensity conditioning was employed in 24% of patients. T-cell depletion was applied in 87% and 26% of transplants from MUD and HLA-identical siblings, respectively. According to the EBMT risk-score, 45% of patients were 'low-risk', 31% 'intermediate-risk' and 24% 'high-risk'. Following allo-HSCT, 87% of patients achieved complete remission. At 5years, relapse-free survival was 36% and non-relapse mortality (NRM) was 24%, while relapse occurred in 40%. Patient age and the EBMT score had an impact on overall survival. Relapse-free survival was higher in MUD than in HLA-identical sibling HSCT, with no difference in NRM. In conclusion, this study confirmed that allo-HSCT represents a valid strategy to achieve cure in a reasonable proportion of patients with aCML, with young patients with low EBMT risk score being the best candidates.

Sickle cell disease: an international survey of results of HLA-identical sibling hematopoietic stem cell transplantation

AbstractDespite advances in supportive therapy to prevent complications of sickle cell disease (SCD), access to care is not universal. Hematopoietic cell transplantation is, to date, the only curative therapy for SCD, but its application is limited by availability of a suitable HLA-matched donor and lack of awareness of the benefits of transplant. Included in this study are 1000 recipients of HLA-identical sibling transplants performed between 1986 and 2013 and reported to the European Society for Blood and Marrow Transplantation, Eurocord, and the Center for International Blood and Marrow Transplant Research. The primary endpoint was event-free survival, defined as being alive without graft failure; risk factors were studied using a Cox regression models. The median age at transplantation was 9 years, and the median follow-up was longer than 5 years. Most patients received a myeloablative conditioning regimen (n = 873; 87%); the remainder received reduced-intensity conditioning regimens (n = 125; 13%). Bone marrow was the predominant stem cell source (n = 839; 84%); peripheral blood and cord blood progenitors were used in 73 (7%) and 88 (9%) patients, respectively. The 5-year event-free survival and overall survival were 91.4% (95% confidence interval, 89.6%-93.3%) and 92.9% (95% confidence interval, 91.1%-94.6%), respectively. Event-free survival was lower with increasing age at transplantation (hazard ratio [HR], 1.09; P < .001) and higher for transplantations performed after 2006 (HR, 0.95; P = .013). Twenty-three patients experienced graft failure, and 70 patients (7%) died, with the most common cause of death being infection. The excellent outcome of a cohort transplanted over the course of 3 decades confirms the role of HLA-identical sibling transplantation for children and adults with SCD.

In patients with chronic aplastic anemia, bone marrow\u2013derived MSCs regulate the Treg/Th17 balance by influencing the Notch/RBP-J/FOXP3/ROR\u03b3t pathway

The standard treatment for aplastic anemia (AA) in young patients is a matched sibling hematopoietic stem cell transplant. Transfusion of a chronic AA patient with allogeneic bone marrow–derived mesenchymal stromal cells (BMMSCs) is currently being developed as a cell-based therapy, and the safety and efficacy of such transfusions are being continuously improved. Nevertheless, the mechanisms by which BMMSCs exert their therapeutic effects remain to be elucidated. In this study, mesenchymal stromal cells (MSCs) obtained from bone marrow donors were concentrated and intravenously injected into 15 chronic AA patients who had been refractory to prior immunosuppressive therapy. We showed that BMMSCs modulate the levels of Th1, Th2, Th17 and Treg cells, as well as their related cytokines in chronic AA patients. Furthermore, the percentages of Th1 and Th17 cells among the H-MSCs decreased significantly, while the percentage Treg cells increased. The Notch/RBP-J/FOXP3/RORγt pathway was involved in modulating the Treg/Th17 balance after MSCs were transfused in vitro. Additionally, the role played by transfused MSCs in regulating the Treg/Th17 balance via the Notch/RBP-J/FOXP3/RORγt pathway was further confirmed in an AA mouse model. In summary, in humans with chronic AA, BMMSCs regulate the Treg/Th17 balance by affecting the Notch/RBP-J/FOXP3/RORγt pathway.

FLAG-IDA, Possible Breakthrough in Treatment of Refractory Acute Myeloid Leukemia in the Context of Hematopoietic Stem Cell Transplantation: Single Center Experience

Abstract Introduction. Acute myeloid leukemia (AML) represents an entity well defined among the hematological malignnant diseases from diagnostic and therapeutic point of view. Still, big concern remains for those patients where the induction therapy fails. Classified in the group of refractory AML these patients are with poor prognosis. There are numerous attempts in providing the best surviving results by administration of appropriate therapy. Our center presents its experience in treating patients with refractory AML by administration of FLAG-Ida regimen, followed by hematopoietic stem cell transplanttation, autologous or allogeneic, depending on the availability of HLA matched sibling donor of hematopoietic stem cells. Methods. In patients with refractory AML, administering FLAG-Ida chemotherapy we have achieved complete remission in 22 patients (47%). Average age of the treated group of patients was 36.6 years (17-53). All of them proceeded to high-dose chemotherapy and underwent hematopoietic stem cell transplantation (HSCT). We performed autologous HSCT in 13 patients, and allogeneic HSCT in 9 patients. Median time to HSCT was 6.6 months (4-10), and in most of the patients we used myeloablative conditioning (MAC). Results. The disease-free survival in our group of patients is 74 months (22-148). The longest overall survival was 148 months and was registered in a patient with allogeneic sibling HSCT. We can conclude that FLAG-Ida regimen is an appropriate and suitable salvage chemotherapy protocol for patients with refractory AML especially when it is used in the context of preparation for HSCT.

Prophylactic Danshen Injection Combined with Prostaglandin E1 and Low-dose Heparin may prevent Hepatic Veno-occlusive Disease after Hematopoietic Stem Cell Transplantation: A Single-center Study in China

Objective: To investigate the effect of Danshen injection combined with prostaglandin E1 and low-dose heparinon prevention of hepatic veno-occlusive disease (HVOD) after hematopoietic stem cell transplantation (HSCT). Methods: A total of 126 patients undergoing HSCT between January 2008 and June 2015, received a combined prophylactic regimen of intravenous Danshen 20-30 ml/day, prostaglandin E 120-30 μg/d, and subcutaneous injection of low-dose heparin (100 U/kg/day) for prevention of HVOD. The incidence of HVOD and adverse events associated with this prophylactic regimen were observed. Results: Among 126 patients, 65 received autologous peripheral blood stem cell transplant, 34 received HLAidentical sibling HSCT, six received HLA mismatched siblingHSCT, seven received HLA-matched unrelated HSCT, and 14 received HLA-mismatched unrelated HSCT. No adverse reaction or coagulation disorder associated with this prophylactic regimen was observed. Only one case with acute myeloid leukemia (CR2) developed HVOD seven days after receiving myeloablative chemotherapy with oral busulfan and cyclophosphamide followed by HLAmismatched unrelated peripheral blood stem cell transplantation. This patient died of HVOD. Conclusion: Danshen injection combined with prostaglandin E1 and low-dose heparin is a safe and effective regimen for the prevention of HVOD after HSCT.

Matched unrelated donor hematopoietic stem cell transplantation - our results

Introduction. Allogeneic stem-cell transplantation is only potentially curative therapy for variety of hematology malignancies, such as acute and chronic leukemia, myelodisplastic syndrome and aplastic anemia, but also promising treatment option for other disorders. If we know that only 25% of patients have an human leukocyte antigen identical sibling donor, it is obvious that matched unrelated donor hematopoietic stem cell transplantation is an alternative for the rest of the patients. Material and Methods. Since 2013, matched unrelated donor hematopoietic stem cell transplantation has been performed routinely in the Military Medical Academy. Results. We hereby present the outcome after 77 procedures in 75 patients. Considering primary diseases, 35 patients had acute myeloid leukemia, 25 patients had acute lymphoid leukemia, 5 patients had chronic myeloid leukemia, 9 patients had myelodisplastic syndrome and we performed the transplant on 1 patient with chronic lymphocyte leukemia, 1 patient with aplastic anemia and 1 patient with T lymphoblastic lymphoma. Conclusion. It is difficult to make clear conclusions based on this heterogeneous group of patients, but it seems that these results are encouraging. Future research will be performed to evaluate matched unrelated donor and identical sibling hematopoietic stem cell transplantation in the homogenous groups with respect to primary diseases.

At Least 20% Donor Myeloid Chimerism Is Necessary to Reverse the Sickle Phenotype after Allogeneic Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is the only curative option for patients with sickle cell disease (SCD). HLA-matched sibling HSCT has become increasingly successful, and haploidentical approaches are being explored to increase the donor pool. Advances have also been made in gene therapy such that clinical trials are now underway for the first time in patients with SCD. The question of what percentage of donor chimerism is necessary to cure SCD is critical in identifying the target percentage of the transferred globin gene needed to reverse SCD. One study showed that a whole blood donor chimerism level as low as 11% was sufficient to render patients free of SCD1; however, lineage specific chimerism was not performed. We have previously demonstrated that peripheral blood myeloid chimerism reflects the HSC compartment. We sought to determine the percentage of donor myeloid chimerism (DMC) necessary to reverse the sickle phenotype in our patients who underwent HSCT.In protocols testing both HLA-matched and haploidentical nonmyeloablative HSCT in over 70 patients with SCD, we identified 3 who despite robust initial engraftment experienced declining DMC levels over prolonged follow up eventually associated with return of SCD. All 3 patients’ donors had sickle cell trait with HbS ranging from 36-40%. Percentages of DMC and HbS were monitored at day 100 and at least every 6-12 months post-transplant thereafter. The 3 patients initially achieved nearly 100% DMC; however, their chimerism levels slowly decreased over time (see Figure 1). As long as mean DMC was >20%, mean %HbS remained less than 50% (similar to their sickle cell trait donors) and the patients stayed free of SCD-related symptoms. However, mean DMC at 2, 3, 4, and 5 years post-transplant fell below 20%, were 18, 12, 11, and 10%, and were associated with mean %HbS levels of 52.5, 51.6, 57.8, and 64.2%. Further, 2 of the patients had return of their recurrent painful crises, and the third patient with moyamoya syndrome developed severe anemia requiring re-initiation of chronic transfusion therapy.We subsequently developed a mathematical model to test the hypothesis that the percentage of necessary DMC is determined solely by the differences between donor and recipient red blood cell (RBC) half-lives. The model incorporates donor and recipient stem cell kinetics (self renewal and differentiation), which are assumed to be identical, as well as donor and recipient RBC survival times, which are known to be different. The model assumes first order kinetics for erythropoiesis and RBC senescence/destruction. It predicts the fraction of donor RBC as a function of DMC and donor/recipient RBC lifetimes. Although we did not directly measure RBC lifetimes, we identified 4 patients with SCD in the literature where reticulocyte percentages ranged from 9.0 to 21.0% and corresponding RBC half-lives determined by radioactive sodium chromate were 1 to 11 days2. We assumed that in erythropoietic homeostasis, RBC lifetime must be proportional to the inverse of the reticulocyte fraction; and we confirmed this relationship using data from these 4 patients with a good coefficient of determination (R2= 0.91). Therefore we reasoned that (at stable hemoglobin concentration) the reticulocyte fraction is a good proxy for RBC lifetime. Figure 1 depicts a comparison between the measured and our model predicted HbS fractions in our 3 patients transplanted with sickle cell trait donors using a mean sickle RBC lifetime of 7 days. As observed in our 3 patients, our model predicts that DMC of at least 20% is necessary to reverse the sickle phenotype.Therefore, our model predicts that genetic strategies aimed at SCD must achieve correction levels of at least 20% to reverse the sickle phenotype. Further, the mechanism explaining why a minority of donor myeloid cells is adequate is due soley to the vast differences in RBC survival between donor and recipient cells. Lastly, recipient RBC survival is lowest in patients with the highest reticulocyte counts suggesting that gene therapy may be most efficacious in subjects with high reticulocyte percentages as our model predicts that lower levels of correction would be sufficient in this setting. Further studies are indicated to validate our findings.1. Walters MC et al. Biol Blood Marrow Transplant. 2001;7(12):665-673.2. Weinstein IM et al. Blood. 1954;9(12):1155-1164. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Reduced Non Relapse Mortality (NRM) and Survivable Acute Graft Versus Host Disease (GVHD) in the Current Era of Myeloablative Ex Vivo T-Cell Depleted (TCD) Transplantation

Introduction:Little is known about the lethality of acute GVHD (aGVHD) in T -cell depleted (TCD) allogeneic hematopoietic stem cell transplantation (HSCT). We examined the incidence of aGVHD and its relative contribution to non relapse mortality (NRM) in a cohort of consecutive TCD HSCT at a single institute.Methods:We report 132 consecutive subjects who had undergone TCD HLA-identical sibling HSCT between 2006 and 2016 for hematologic malignancies. All subjects received conditioning with Fludarabine 125mg/m2, Cytoxan 120 mg/kg and 1200 cGy total body irradiation (TBI) (<age 55 years) or 400-600 cGy (³age 55) followed by either a CD34+ selected (n=112) or CD3/19 depleted (n=20) peripheral blood stem cell graft with a T cell addback of 5-50x10e4CD3+/kg (Miltenyi CliniMACS, resulting in 3.5 to 4-log TCD). Low dose cyclosporine was used until day 21 for GVHD prophylaxis.Thirty-six subjects were over the age of 55 years, 66 were females and 66 were males. Transplant indications were acute leukemia (92), myelodysplastic / myeloproliferative syndromes (26), lymphoid malignancies (7) and chronic myelogenous or myelomonocytic leukemia (7). Fifty-three percent of subjects were at a high risk of relapse. The median follow-up post HSCT was 4.3 years.Results:The incidence of Grade 1-2 and 3-4 aGVHD were 51.6% and 19%, respectively. Of these, 15% of aGVHD was steroid refractory and was treated with infliximab/basiliximab or with mesenchymal stromal cells. Extensive or limited chronic GvHD was observed in 30% and 24% of subjects. 74% of those at risk developed cytomegalovirus (CMV) reactivation. The Kaplan-Meier (KM) estimate for overall survival (OS), NRM and cumulative incidence of relapse (CIR) for the entire cohort was 71%, 14.6% and 24% respectively at one year, and 52%, 32.5% and 39% at 5 years. We considered the impact of CMV reactivation, slow donor lymphoid chimerism and steroid refractory aGVHD on NRM. However there was no significant impact from CMV reactivation or slow (> 31 days) achievement of complete donor lymphoid chimerism. Significantly improved outcomes were noted for those transplanted beyond 2012: OS, NRM and CIR being 82%,6.2% and 20% at one year, and 68%, 6.2% and 41% at 3 years. Cox proportionate hazard modeling identified steroid refractory aGVHD (HR 4.0, P=0.007) and transplant prior to 2012 (HR 6.7, P=0.001) as significant factors impacting NRM.Conclusions:T cell addback after ex vivo TCD HSCT was associated with a significant burden of aGVHD. Steroid refractory aGVHD impacted NRM, but slow lymphoid engraftment, disease risk, CMV reactivation and age did not. Significant improvements in NRM in the current era suggest greatly improved salvage of steroid refractory aGVHD. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Neurocognitive Functioning in Adults Who Underwent Nonmyeloablative HLA-Matched Sibling Hematopoietic Stem Cell Transplant (SCT) for Sickle Cell Disease (SCD)

Individuals with SCD are at risk for neurocognitive impairments. While potentially curative, SCTs come with their own risk of neurotoxicities, particularly from radiation and high-dose ablative chemotherapies. Newer, nonmyeloablative regimens may prevent some of these toxicities. This study examines the long-term cognitive impact of nonmyeloablative transplants in adults with SCD. Seventeen adults (11 males; mean age = 32.2 years, SD=9.0, range 17–52) participated in neuropsychological evaluations before transplant and 12 months post-transplant, as part of a research protocol at the National Heart Lung and Blood Institute. Donors were HLA-matched siblings; the conditioning regimen consisted of alemtuzumab and 300cGy total body irradiation, and they received sirolimus for graft-versus-host disease prophylaxis. Evaluations assessed global cognition, processing speed, memory, attention, and executive functions. Patients completed the PROMIS Physical Functioning questionnaire. Global cognition was within normal limits. Mean Verbal and Performance IQ scores were average at baseline and follow-up, with no significant changes noted. Mean processing speed scores were average, and increased significantly from baseline (M=92.1, SD=10.1) to 12 months (M=99.2, SD=11.6, t=2.1, p=.013). Mean scores on memory, attention and executive tests were average and stable across time points. No group declines in mean cognitive scores were noted. Mean t-scores on the physical functioning questionnaire increased from 41.6 (SD=4.7) to 49.0 (SD=10.0; t=3.4, p=.01), indicating significant improvement from baseline to 12 months post-transplant. Hemoglobin levels increased significantly from pre-transplant (M=9.1, SD=0.9) to post-transplant (M=13.1, SD=2.2; t=8.9, p<.0001). In this small sample, a comparison of neurocognitive scores from baseline to 12 months post-nonmyeloablative SCT does not indicate any deleterious effects from transplant. In fact, a significant improvement emerged in mental processing speed. Physical functioning also improved per patient questionnaires. As suggested by some prior research, the significant increase in hemoglobin levels may underlie improvements in processing speed.

Low Radiation Dose and Low Cell Dose Increase the Risk of Graft Rejection in a Canine Hematopoietic Stem Cell Transplantation Model

The canine hematopoietic stem cell transplantation (HSCT) model has become accepted in recent decades as a good preclinical model for the development of new transplantation strategies. Information on factors associated with outcome after allogeneic HSCT are a prerequisite for designing new risk-adapted transplantation protocols. Here we report a retrospective analysis aimed at identifying risk factors for allograft rejection in the canine HSCT model. A total of 75 dog leukocyte antigen–identical sibling HSCTs were performed since 2003 on 10 different protocols. Conditioning consisted of total body irradiation at 1.0 Gy (n = 20), 2.0 Gy (n = 40), or 4.5 Gy (n = 15). Bone marrow was infused either intravenously (n = 54) or intraosseously (n = 21). Cyclosporin A alone or different combinations of cyclosporine A, mycophenolate mofetil, and everolimus were used for immunosuppression. A median cell dose of 3.5 (range, 1.0 to 11.8) total nucleated cells (TNCs)/kg was infused. Cox analyses were used to assess the influence of age, weight, radiation dose, donor/recipient sex, type of immunosuppression, and cell dose (TNCs, CD34+ cells) on allograft rejection. Initial engraftment occurred in all dogs. Forty-two dogs (56%) experienced graft rejection at median of 11 weeks (range, 6 to 56 weeks) after HSCT. Univariate analyses revealed radiation dose, type of immunosuppression, TNC dose, recipient weight, and recipient age as factors influencing long-term engraftment. In multivariate analysis, low radiation dose (P < .001) and low TNC cell count (P = .044) were identified as significant independent risk factors for graft rejection. Peripheral blood mononuclear cell chimerism ≥30% (P = .008) and granulocyte chimerism ≥70% (P = .023) at 4 weeks after HSCT were independent predictors of stable engraftment. In summary, these data indicate that even in low-dose total body irradiation–based regimens, the irradiation dose is important for engraftment. The level of blood chimerism at 4 weeks post-HSCT was predictive of long-term engraftment in the canine HSCT model.

Comparing Outcomes with Bone Marrow or Peripheral Blood Stem Cells as Graft Source for Matched Sibling Transplants in Severe Aplastic Anemia across Different Economic Regions

Bone marrow (BM) is the preferred graft source for hematopoietic stem cell transplantation (HSCT) in severe aplastic anemia (SAA) compared with mobilized peripheral blood stem cells (PBSCs). We hypothesized that this recommendation may not apply to those regions where patients present later in their disease course, with heavier transfusion load and with higher graft failure rates. Patients with SAA who received HSCT from an HLA-matched sibling donor from 1995 to 2009 and reported to the Center for International Blood and Marrow Transplant Research or the Japan Society for Hematopoietic Cell Transplantation were analyzed. The study population was categorized by gross national income per capita and region/countries into 4 groups. Groups analyzed were high-income countries (HIC), which were further divided into United States–Canada (n = 486) and other HIC (n = 1264); upper middle income (UMIC) (n = 482); and combined lower-middle, low-income countries (LM-LIC) (n = 142). In multivariate analysis, overall survival (OS) was highest with BM as graft source in HIC compared with PBSCs in all countries or BM in UMIC or LM-LIC (P < .001). There was no significant difference in OS between BM and PBSCs in UMIC (P = .32) or LM-LIC (P = .23). In LM-LIC the 28-day neutrophil engraftment was higher with PBSCs compared with BM (97% versus 77%, P = .002). Chronic graft-versus-host disease was significantly higher with PBSCs in all groups. Whereas BM should definitely be the preferred graft source for HLA-matched sibling HSCT in SAA, PBSCs may be an acceptable alternative in countries with limited resources when treating patients at high risk of graft failure and infective complications.

Hematopoietic Stem Cell Transplantation from HLA Identical Sibling Forsickle Cell Disease an International Survey on Behalf of Eurocord-Monacord, EBMT Paediatric Disease Working Party and CIBMTR

Introduction:Hematopoietic stem cell transplantation (HSCT) is, to date, the only curative therapy for sickle cell disease (SCD). However, HSCT is offered to relatively few patients with SCD for a number of reasons including lack of a suitable HLA-matched donor, lack of consensus on indications for HSCT, the potential for trading one chronic condition (i.e., SCD) for another, such as chronic graft-versus-host disease (GVHD), and the mortality associated with the procedure. To-date, most HSCTs for SCD have utilized matched siblings as donors and are performed in children and adolescents. We report outcomes after HLA-matched sibling HSCT of patients reported to the Eurocord-Monacord/European Group for Blood and Marrow Transplantation (EBMT) and Center for International Blood and Marrow Transplant Research (CIBMTR).Material and methods:One thousandpatients with SCD received HLA identical sibling HSCT between 1991 and 2013; n=439 from CIBMTR and n=561 from EBMT centers. HSCTs were performed in 90 centers in 23 countries.Results:Median age at HSCT was 9 years (range 1-54y); 85% of patients were aged <16 years. Approximately half of patients were female and 53% of HSCTs were performed after 2007. Most patients (94%) were homozygotes for hemoglobin S (HBS). The most common indication for HSCT was stroke. Other indications included: central nervous system event lasting longer than 24 hours, elevated cerebral arterial velocity, acute chest syndrome or vaso-occlusive crisis requiring hospitalization. Red blood cell transfusions were given before HSCT to 93% and hydroxyurea to 56% of the evaluable patients (N=510). Most HSCTs (n=872; 87%) used myeloablative-conditioning regimens, mainly based on the combination of busulfan with cyclophosphamide (n=719; 82%) or fludarabine (n=82; 9%). One hundred and twenty six patients (13%) received reduced intensity conditioning regimens; fludarabine with cyclophosphamide was the predominant regimen (n=48; 38%). Most regimens included in vivo T-cell depletion (71%) with anti-thymocyte globulin (n=630) or alemtuzumab (n=76). The predominant GVHD prophylaxis regimens were cyclosporine alone (19%), or combined with methotrexate (56%). The predominant stem cell source was bone marrow (84%); peripheral blood and cord blood were employed in 7% and 9% of patients, respectively. The median follow-up was 45 (1.1-324.6) months.The cumulative incidence (CI) of neutrophil engraftment at day+60 was 98% (96.6% for CB, 98.3% for BM and 95.2% for PB) with a median time to recovery of 19 days, while that for platelet engraftment was 98 % (96±2% for CB, 99±1% for BM and 98±9% for PBSC) with a median time to recovery of 25 days. Twenty-six patients experienced primary and 47 patients secondary graft failure; 67 patients died mainly due to GVH or infection. The 3-year probabilities of overall (OS) and event-free survival (EFS, alive with engraftment) were 94% (95% CI 92-95) and 90% (95% CI 68-82), respectively. According to stem cell source, 3-year OS was 99% after CB, 94% after BM and 80% after PBS (p<0.0001). In multivariate analysis, every year in age increment (HR 1.1, 95% CI 1.07-1.14, p<0.001) and use of peripheral blood (HR 3.43, 95% CI 1.49-7.88, p=0.004) were associated with higher mortality. In univariate analysis, EFS was better in patients receiving myeloablative compared to reduced intensity conditioning (91±1% vs 82 ±1%, respectively; p<0.001). In multivariate analysis, EFS was lower with every year in age increment (HR 1.05, 95% CI 1.02-1.07, p<0.001), peripheral blood grafts (HR 1.83, 95% CI 1.07-3.15, p=0.03) and HSCTs prior to 2000 (HR 0.77, 95% CI 0.64-0.92, p=0.005). CI of acute GVHD grade 2-4 was 14.4% (12.2-16.7) of chronic GVH 13.3 (11-15.8). Risks of acute GVHD were higher with increasing age (HR1.04 95% CI 1.01-1.07, p=0.008). None of the variables tested were associated with chronic GVHD.Conclusion:This large registry based international study shows that HLA identical sibling transplant is successful more than 90% of the patients with severe SCD with limited transplant related complications (rejection, GVHD). Strategies aimed at lowering graft failure and GVHD are desirable to further optimize the observed 3-year event-free survival. Importantly, these data should increase awareness to early referral to HSCT of patients with severe SCD. DisclosuresWalters:ViaCord and AllCells, Inc: Other: Medical director. Bertrand:ERYTECH Pharma: Consultancy. Peters:Medac: Research Funding; Fresenius: Research Funding; Amgen: Research Funding; Jazz: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Sanovi: Research Funding; Pierre-Fabre: Research Funding.

TGFB1 Functional Polymorphisms in Sibling HSCT. "Tto be or Not Tto be"

Allogeneic hematopoietic stem cell transplantation (HSCT) using sibling donors is a life-saving intervention for patients with hematological malignancies. It is recognized that numerous genetic factors in both patient and donor play a role in the outcome of the procedure. TGF beta 1 is a member of a highly pleiotrophic family of growth factors involved in the regulation of numerous immunomodulatory processes. Several functional polymorphisms have been identified in TGF-B1 gene, such as a single nucleotide polymorphism (SNP) at codon 10 of exon 1. We have previously published significant impact of this SNP on unrelated donor (UD) transplant outcome, predominantly on Non Relapse Mortality (NRM) and acute Graft-vs.-Host-Disease (aGVHD). To date there are no published data in large sibling donor HSCT cohorts looking at survival outcomes. We have hypothesized that TGF-B1 SNP may influence the outcome of sibling donor HSCT similarly to UD. Preliminary data were presented at ASH meeting 2014. Two hundred and seventeen patient/donor pairs who underwent a sibling donor HSCT in our centers were genotyped for the presence of a SNP at codon 10 (rs1982073) by an allele-specific PCR. Transplants took place between January 2000 and January 2015 and the median follow up time was 4.4 years. Median age was 33 years and 58% were male. The prevalent diagnoses were acute myeloid leukemia 64 (29%), acute lymphoid leukemia 49 (23%), lymphoproliferative disorders 28 (13%), myelodysplastic syndrome 26 (12%) and myeloproliferative neoplasm 20 (9%). Early stage of the disease was determined in 42%. Myeloablative conditioning regimens were used in 58% of transplants; the source was PBSC in 90% of the patients. The patients' observed SNP frequencies were TT 23%, TC 55% and CC 22%, and for the donors were 26%, 53% and 21% respectively. No significant impacts were observed in the full cohort analysis. When we analyzed the myeloablative cohort, significant differences were founded. Similarly to what we observed in UD, codon 10 CC patients had a significant increase in 1 year treatment related mortality (32% vs. 9%, p=0.01) and Non Relapse Mortality (NRM) (1-3 years CC 31-31% vs. TC/TT 8-13%, Gray's test p=0.04) (figure 1). A very interesting finding was in donor's genotype. Codon 10 TT donor's receptors experienced a significant increase in aGVHD (72% vs. 49%, p=0.03), with 56% of this grades 2-4. Interestingly this group had no protection in terms of relapse, but the opposite, although not significant (1-3 years TT 36-40% vs. TC 17-34% vs. CC 9-13%, Gray's test p=0.1). Finally TT donors had a significant decrease in Overall Survival (OS) compared to other genotypes (1-3 years TT 69-50% vs. TC/CC 77-69%, log-rank p=0.04) (figure 2). No differences were observed in donor genotype in terms of NRM. Besides confirming that as in UD, patient codon 10 CC had an increase in NRM, we conclude that in sibling donor-myeloablative HSCT codon 10 TT donors might be associated with an increase in aGVHD with no protection in relapse and a significant decrease in OS. These results should be confirmed in larger series. Identification of these SNPs pre-transplant will allow for transplant conditioning and immunosuppression regimens to be tailored to the individual patient, as well as assisting in the most appropriate choice of donor. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Association of KIR2DS4 and its variant KIR1D with the outcome after HLA- identical sibling hematopoietic stem cell transplantation

Association of KIR2DS4 and its variant KIR1D with the outcome after HLA- identical sibling hematopoietic stem cell transplantation

Current attitudes of parents and patients toward hematopoietic stem cell transplantation for sickle cell anemia.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only available cure for sickle cell anemia (SCA). HSCT-associated risks are one of many barriers to its widespread use for SCA. The study objective was to assess parent and patient perceptions of HSCT in the era of more widespread knowledge about HSCT for SCA. We surveyed parents of children with SCA and adolescents with SCA using the standard reference gamble paradigm. Survey responses between Africans (A) and African Americans (AA) and between parents and adolescents were compared. Seventy-two percent (64/89) of the respondents were willing to accept ≥ 5% risk of mortality, while 57% said they would accept a risk of ≥ 10% of graft versus host disease (GVHD). Twenty-two percent were unwilling to accept any risk of mortality or GVHD. Risk averseness did not differ between A or AA respondents. Fifty-six percent of respondents were willing to accept infertility post-HSCT. These data suggest that the majority of parents and adolescents are willing to accept the current risks associated with matched sibling HSCT for SCA. However, there continue to be significant numbers of parents and adolescents who are unwilling to accept any risk of HSCT-associated mortality or GVHD.

Children after Allogeneic Hematopoietic Cell Transplantation Can Develop BK Virus Nephropathy: Pilot Data Using Urinary Polyomavirus-Haufen Testing

s / Biol Blood Marrow Transplant 21 (2015) S206eS239 S230 Results: Five patients with PIDD who underwent HSCT were recruited to date, and two have been infused with VSTs at 5x10E6 cells/m2/dose. The manufactured VSTs had a CD4+ Tcell predominance with detectable antiviral activity against CMV pp65/IE1, EBV-LMP2/EBNA1, and Adv-Hexon/Penton epitopes based on IFN-g ELISpot assays. All VSTs were nonalloreactive in chromium release assays utilizing allogeneic PHA blasts as targets ( 1,000,000 to<1000 copies/ml. The second patient was treated for CMV viremia after matched sibling HSCT for MHC-II deficiency, and had viral clearance of CMV within 1-month post-VST infusion. One patient developed Grade I skin GVHD post VSTs which resolved within 1 week and was associated with the tapering of immune suppression. Conclusions: VSTs are safe and effective for control of viral infections in patients with PIDD following HSCT. We plan further evaluation of virus-specific CTL for patients with PIDD both before and after HSCT.

Hemophilic donor used for sibling HSCT in aplastic anemia

We report a case of 19 year old female (carrier of hemophilia) with severe aplastic anemia who underwent Hematopoetic stem cell transplantation. Sibling donor was 13 year male suffering from hemophilia A, with factor VIII levels of 3 units per liter. Recipient's factor VIII level was maintained after HSCT. She is transfusion independent and without symptoms of hemophilia after a follow up of 24 months.