Reconstitution of CD52-Negative CD4 T Cells after Alemtuzumab-Based T Cell Depleted Allogeneic Hematopoietic Stem Cell Transplantation

Abstract The human CD52 molecule is the target of the monoclonal antibody Alemtuzumab, which is used for treating patients with chemo-refractory chronic lymphocytic leukemia as well as for T cell depletion (TCD) in the context of allogeneic hematopoietic stem cell transplantation (HSCT). The molecule is expressed on the surface of lymphocytes, dendritic cells and to a lesser extent on blood-derived monocytes. Previously, investigators have demonstrated that the surface expression of CD52 on T cells is down-regulated after in vitro incubation with Alemtuzumab. By treating purified human CD4 T cells over 4 hours with 10 μg/mL Alemtuzumab in medium supplemented with 10% human AB serum in vitro…

P046 Deconstructing HLA-C mismatch in hematopoietic stem cell transplantation

Contrary to other HLA loci, allele vs antigen mismatches in HLA-C appear to differentially impact HSCT outcome. Aim of this study was to investigate the independent role of other factors characterizing a patient’s HLA-C non-shared allele, in HSCT outcome as well as their distribution in allele vs antigen mismatched cases. 288 9/10 HLA-C mismatched unrelated transplant pairs, were additionally genotyped by sequence based typing for rs9264942(C/T) and rs67384697(ins/del), which are considered surrogate markers of HLA-C expression levels. A proxy MFI model as previously described (Petersdorf et al., Blood 2014), was also implemented in the analysis. All patient non-shared alleles were characte…

Impact of Pre-Transplant Ruxolitinib in Myelofibrosis Patients on Outcome after Allogeneic Stem Cell Transplantation

Abstract Introduction Ruxolitinib is the first approved drug for treatment of myelofibrosis. Major effects are reduction in spleen size and improvement of constitutional symptoms. Because spleen size and constitutional symptoms may influence outcome after allogeneic stem cell transplantation (ASCT), ruxolitinib is recommended before stem cell transplantation in order to reduce therapy-related morbidity and mortality and improve outcome (EBMT/ELN recommendation, Leukemia 2015) The aim of this retrospective study was to evaluate the impact of pretreatment with ruxolitinib in comparison to transplantation of ruxolitinib-naïve MF patients with regard to outcome after ASCT. Patients and methods …

Donors with KIR-Bx Haplotypes Improve Outcome of Unrelated Hematopoietic Stem Cell Transplantation for Recipients with a Myeloid Malignant Disease and a C1 Ligand Phenotype

relapse, or transplant related mortality (TRM) (p1⁄40.2, p1⁄40.1, p1⁄40.08, respectively). To investigate why higher CPSS scores were associated with higher mortality, we performed analysis restricted to patients with relapse following HCT. Those with intermediate-2/high riskhadnearly two-fold increase in riskof death after relapse compared to thosewith low/intermediate1 CPSS scores. Corresponding rates for low/intermediate-1 risk groups,OSat1year, 3years, and5yearswere61%,48%, and44% respectivelyand for intermediate-2/high riskgroupswere 38%, 32%, and19%respectively.OSofpatientswho receivedpre-HCT treatment with hypomethylating agents, chemotherapy, or both was not different compared to th…

P043 HLA-DPB matching and donor cytomegalovirus positive (CMV+) status: An “unconventional alliance” associated with a decreased relapse incidence in unrelated hematopoietic stem cell transplantation (UHSCT)

Aim While the role of HLA-DPB1 (DP) compatibility in uHSCT regarding graft versus host disease (GVHD)- and graft versus leukaemia (GVL)-effects has been extensively discussed, its interaction with donor CMV status (dCMV), remains elusive. The aim of this study was, to investigate the impact of dCMV status in DP matched (DPM) and mismatched (DPMM) uHSCT. Methods 1749 HSCT transplant (Tx) pairs were DP genotyped with an exon 2 amplicon based NGS approach in order to assess their DP matching status. CMV sero-status as well as clinical data were retrieved from the German Stem Cell Registry. Overall survival (OS), relapse incidence (RI) and chronic GvHD (cGvHD) were defined as endpoints, while s…

Functionally Altered GPI-Anchor Negative Treg Following Alemtuzumab-Based T-Cell Depletion Are Associated with Acute Gvhd.

Abstract Abstract 3059 Introduction: The monoclonal anti-CD52antibody Alemtuzumab is frequently used for T-cell depletion (TCD) in the context of allogeneic hematopoietic stem cell transplantation (HSCT) to prevent graft versus host disease (GVHD). We previously demonstrated the long term persistence of functionally impaired glycosylphosphatidylinositol (GPI)-anchor negative effector T-cells in patients receiving high dose (100mg) Alemtuzumab in combination with a dose reduced conditioning regimen (Fludarabin + Melpahlan) (Meyer, Wagner et al. BMT 2010). Despite of Alemtuzumab-mediated TCD, half of our patients developed acute GVHD. Since regulatory T cells (Treg) play a major role for cont…

CD8-Depleted Donor Lymphocyte Infusions Convert Mixed into Complete Donor T-Cell Chimerism after T-Cell Depleted Allogeneic Stem Cell Transplantation.

Abstract Donor lymphocyte infusions (DLI) are increasingly used to treat minimal residual disease or mixed hematopoietic donor-recipient chimerism in T-cell depleted allogeneic stem cell transplantation (SCT). In addition, several clinical trials currently investigate the prophylactic application of DLI to promote donor T-cell reconstitution after transplantation. However, DLI carry a substantial risk of inducing graft-versus-host disease (GVHD). We investigate DLI heavily depleted of CD8 T cells using a clinical grade immunomagnetic in vitro procedure in an ongoing clinical study [Meyer et al., Blood2007, 109:374]. These DLI are administered in a prophylactic setting to patients with hemat…

The CD38-Positive and CD38-Negative Subsets of CD34(high)-Positive Primary Acute Myeloid Leukemia Blasts Differ Considerably in the Expression of Immune Recognition Molecules

Abstract Acute myeloid leukemia (AML) is thought to arise from a rare putative ‘leukemic stem cell’ that is capable of self-renewal and formation of leukemic blasts. Serial xenotransplantation studies in immunodeficient mice have shown that this leukemia-initiating cell resides at very low numbers within CD34(high)-positive CD38-negative AML cells. Thus, immunotherapeutic approaches successfully eradicating this cell compartment should result in cure from disease. The objective of our study was to characterize the immune phenotype of the CD38-negative and CD38-positive subsets of primary CD34(high)-positive AML blasts ex vivo. We obtained therapeutic leukapheresis products from 17 AML patie…

Impact of DLI after In Vivo T-Cell-Depletion: Prophylactic CD8 Depleted or Preemptive CD3pos DLI?

Abstract Introduction: The combination of reduced-intensity conditioning (RIC) with in vivo T-cell depletion by alemtuzumab prior to hematopoietic stem cell transplantation (HSCT) has demonstrated efficient engraftment and reduced graft-versus-host disease (GVHD). However, this regimen is associated with slow lymphocyte recovery leading to a delayed anti-infectious and anti-malignant immunity. DLI can be used to improve immune reconstitution. Here we investigate on the impact of different DLI: prophylactic CD8-depleted DLI vs preemptive non-depleted DLI. Methods: 256 patients with different hematologic malignancies were planned for treatment with DLI after allogeneic HSCT following reduced …

Late Non-Relapse Mortality (NRM) after Standard-of-Care (SOC) CAR-T Cell Therapy for Large B-Cell Lymphoma (LBCL): Frequency, Causes, and Risk Factors.a GLA/DRST Real World Analysis

Abstract Introduction Although the labeled CD19 targeting CAR-T cell constructs axi-cel and tisa-cel are generally associated with an acceptable safety profile, non-relapse deaths can occur. Little is known about timing, causes and predictors of NRM following SOC CAR-T cell therapy for LBCL. Here, we analyzed frequency, causes, and risk factors of non-relapse deaths with focus on late NRM (beyond 4 weeks after dosing) using registry data provided by the DRST, the national partner of the EBMT. Methods Patients were selected from 356 consecutive patients who received SOC CAR-T treatment of LBCL between November 2018 and April 2021 at 21 German centers and were registered with the DRST/EBMT. B…

Real-World Experience of CPX-351 As First-Line Treatment in 188 Patients with Acute Myeloid Leukemia

Abstract Background In a recent phase-III trial CPX-351 (Jazz Pharmaceuticals, Palo Alto, CA), a liposomal encapsulation of cytarabine and daunorubicin, has shown higher remission rates and longer overall survival (OS) in patients aged 60 to 75 years with AML with myelodysplasia-related changes (AML-MRC) or therapy-related AML (t-AML) in comparison to conventional 7+3 regimen. Based on this CPX-351 has been approved in the USA 2017 and in Europe 2018 for adult patients with newly-diagnosed AML-MRC or t-AML. Still, several issues such as age (<60 years), measurable residual disease (MRD), molecular subgroups and outcome after allo-HCT were not addressed in the phase-III trial. Aiming …

Impact of Donor-Recipient Histocompatibility and CMV-Mismatch on Outcome of Allogeneic Stem Cell Transplantation for AML and MDS: A Retrospective Registry Study of the German Stem Cell Transplant Registry (DRST) of the German Working Group for Blood and Marrow Transplantation (DAG-KBT)

Abstract Introduction Allogeneic stem cell transplantation (allo-SCT) is a curative treatment for several hematological diseases. Donor-recipient histo-incompatibility is associated with poorer outcome. Transplant outcome of CMV positive patients is reported to be poorer, if the unrelated donor is CMV negative (CMV-mismatch). Recent developments in transplant strategies including high resolution HLA-typing, toxicity-reduced conditioning regimens, CMV-monitoring, and improved supportive care have made transplants from HLA- as well as CMV- mismatched unrelated donors more feasible. We present a retrospective registry analysis from a large, and recent cohort of patients transplanted under thes…

Hematopoietic stem-cell transplantation for advanced systemic mastocytosis

Purpose Advanced systemic mastocytosis (SM), a fatal hematopoietic malignancy characterized by drug resistance, has no standard therapy. The effectiveness of allogeneic hematopoietic stem-cell transplantation (alloHCT) in SM remains unknown. Patients and Methods In a global effort to define the value of HCT in SM, 57 patients with the following subtypes of SM were evaluated: SM associated with clonal hematologic non–mast cell disorders (SM-AHNMD; n = 38), mast cell leukemia (MCL; n = 12), and aggressive SM (ASM; n = 7). Median age of patients was 46 years (range, 11 to 67 years). Donors were HLA-identical (n = 34), unrelated (n = 17), umbilical cord blood (n = 2), HLA-haploidentical (n = 1)…

Role of Donor Clonal Hematopoiesis in Allogeneic Hematopoietic Stem-Cell Transplantation

Purpose Clonal hematopoiesis of indeterminate potential (CHIP) occurs in the blood of approximately 20% of older persons. CHIP is linked to an increased risk of hematologic malignancies and of all-cause mortality; thus, the eligibility of stem-cell donors with CHIP is questionable. We comprehensively investigated how donor CHIP affects outcome of allogeneic hematopoietic stem-cell transplantation (HSCT). Methods We collected blood samples from 500 healthy, related HSCT donors (age ≥ 55 years) at the time of stem-cell donation for targeted sequencing with a 66-gene panel. The effect of donor CHIP was assessed on recipient outcomes, including graft-versus-host disease (GVHD), cumulative incid…

Transmission of angioimmunoblastic T-cell lymphoma by bone marrow transplant

Accidental transmission of lymphoma by bone marrow transplant is a rarely reported event [1–5], since candidates are only accepted for hematopoietic stem cell donation after a work-up that routinel...

Anti-CD20 immunotherapy as a bridge to tolerance, after allogeneic stem cell transplantation for patients with chronic lymphocytic leukaemia: results of the CLLX4 trial

Centre characteristics and procedure-related factors have an impact on outcomes of allogeneic transplantation for patients with CLL: a retrospective analysis from the European Society for Blood and Marrow Transplantation (EBMT)

Abstract Introduction:Even in the era of novel targeted therapies for the treatment of Chronic Lymphocytic Leukemia (CLL) patients, such as BTK, PI3K and BCL2 inhibitors, allogeneic hematopoietic stem cell transplantations (alloHCT) will remain an important treatment option for a subset of patients with very high risk CLL. The current study focused on the impact of center and procedure-related factors on outcomes after alloHCT, taking into account the impact of patient- and disease-related risk factors. Patients and Methods:Data of 684 CLL patients who received a first alloHCT between 2000 and 2011 were analyzed. Their data were collected as part of the EBMT CLL Data Quality Initiative. Out…

Vaccination with WT1 and PR3 Derived Peptides in Patients with AML/MDS and MUC1 Peptides in Patients with Multiple Myeloma - Preliminary Results.

Abstract Background: It has been demonstrated that the Wilms Tumor gene (WT1) is highly expressed in various types of leukaemia. WT1 expression level reflects the extent of minimal residual disease and significantly increases at relapse. Proteinase 3 (Pr3) is an aberrantly expressed myeloid leukaemia protein and T cells with specificity for both, Wt1 and Pr3 derived antigens, have been generated in vitro from healthy individuals and cancer patients and lysed myeloid leukaemic blasts. MUC1(CD227) is presented on a considerable amount of multiple myeloma cell lines and plasmocytoma cells. MUC1-derived HLA-class I/II epitopes represent universal tumor antigens, which are also expressed by mali…

Donor CD4 T cells convert mixed to full donor T-cell chimerism and replenish the CD52-positive T-cell pool after alemtuzumab-based T-cell-depleted allo-transplantation.

Donor lymphocyte infusions (DLI) are used to resolve mixed T-cell chimerism (TCC) after allo-SCT despite a substantial risk of GVHD. We analyzed the impact of prophylactic CD8-depleted (CD8(depl)) DLI in 20 recipients of anti-CD52 alemtuzumab in vivo T-cell-depleted allografts with declining donor TCC after day +60. A total of 13 patients received CD8(depl) DLI and 7 patients did not. All but one of the DLI patients converted to complete donor T-cell chimeras, whereas only one non-DLI patient converted spontaneously. DLI induced transient acute GVHD in five and extensive chronic GVHD in two patients. These data suggest the use of CD8(depl) DLI as an effective treatment for mixed TCC, partic…

Follow Up On CD8-Depleted Donor-Lymphocyte Infusions After T-Cell Depleted Allogeneic Hemopoietic Stem Cell Transplantation

We applied prophylactic CD8-depleted (CD8depl) donor lymphocyte infusions (DLI) in the setting of T-cell depleted reduced-intensity allogeneic hematopoietic stem cell transplantation (HSCT) in a phase I/II trial. T-cell depletion was carried out by the use of high-dose Alemtuzumab (100 mg or 60 mg for unrelated or sibling donor transplantation, respectively). We have demonstrated the feasibility of this approach after having treated 23 patients in this protocol (Meyer et al. Blood 2007). From 2004 to 2011, 134 patients with different hematologic diseases were included and followed for a median observation time of 1.5 years after transplantation (range, 1.5-9 years). Median age was 56 years …

Human Epidermal Langerhans Cells Replenish Skin Xenografts and Are Depleted by Alloreactive T Cells In Vivo

Abstract Epidermal Langerhans cells (LC) are potent APCs surveying the skin. They are crucial regulators of T cell activation in the context of inflammatory skin disease and graft-versus-host disease (GVHD). In contrast to other dendritic cell subtypes, murine LC are able to reconstitute after local depletion without the need of peripheral blood-derived precursors. In this study, we introduce an experimental model of human skin grafted to NOD-SCID IL2Rγnull mice. In this model, we demonstrate that xenografting leads to the transient loss of LC from the human skin grafts. Despite the lack of a human hematopoietic system, human LC repopulated the xenografts 6 to 9 wk after transplantation. By…

Clinical Validation of a Novel Elispot-Based Diagnostic Assay: Monitoring Cytomegalovirus-Specific Cell-Mediated Immunity and Risk Stratification in Hematopoietic Stem Cell Transplant Recipients

Increasing evidence suggests that impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of uncontrolled CMV reactivations and associated complications in hematopoietic stem cell transplantation (HSCT). No reliable test exists to predict patients at risk of primary and/or recurrent CMV reactivations following HSCT. Accurately assessing CMV-CMI might therefore improve the risk stratification of patients and allow optimizing and individualizing patient care. This study aimed to evaluate the suitability of a novel IFN-γ ELISpot assay (T-Track® CMV), based on the stimulation of peripheral blood mononuclear cells with T-activated® pp65 and IE-1 CMV proteins, to…

Evaluation of six different types of sequential conditioning regimens for allogeneic stem cell transplantation in relapsed/refractory acute myelogenous leukemia – a study of the Acute Leukemia Working Party of the EBMT

The Acute Leukemia Working Party (ALWP) of the EBMT assessed the outcome of allogeneic stem cell transplantation (alloSCT) in patients with relapsed/refractory AML (r/rAML) evaluating six sequential conditioning regimens (SR) groups. A total of 2132 patients were included. LFS at 2 years was 28.9%, 33.6%, 35.3%, 20.6%, 24.4%, and 27% for the FLAMSA-TBI4, FLAMSA-Chemo, Mel-Flu-TBI8, Mel-Treo-Flu, Thio-ETO-Cy-Bu2-Flu, and Clo-ARAC-(Bu2/TBI4)-Cy groups, respectively. In patients55 years of age Mel-Flu-TBI8 had the best LFS, which was statistically significant only in comparison to the Mel-Treo-Flu group, while in patients ≥55 years LFS was best with FLAMSA-Chemo without significant differences…

Biomarker Analysis in Patients (pts) with Steroid-Refractory Acute Graft-Vs-Host Disease (aGVHD) Treated with Ruxolitinib (RUX) or Best Available Therapy (BAT) in the Randomized, Phase 3 REACH2 Study

BACKGROUND aGVHD, a common complication of allogeneic stem cell transplant (alloSCT), is driven by proinflammatory cytokines and chemokines that activate the immune system, resulting in end-organ damage. Steroids are first-line treatment but up to 50% of pts are steroid refractory (SR), resulting in high mortality and morbidity. RUX, a JAK1/JAK2 inhibitor, inhibits cytokine-dependent activation of the JAK-STAT pathway and cell proliferation and differentiation, which prevents worsening of aGVHD and allows recovery. JAK pathway inhibition by RUX may also lead to modulation of proinflammatory cytokines and prognostic GVHD biomarkers. The phase 3 randomized REACH2 trial (NCT02913261) in SR aGV…

Recovery of Varicella-Zoster Virus–Specific T Cell Immunity after T Cell–Depleted Allogeneic Transplantation Requires Symptomatic Virus Reactivation

Abstract Reactivated varicella-zoster virus (VZV) infection causes herpes zoster and commonly occurs after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Because VZV-specific T cell immunity is essential to prevent virus reactivation, we developed an interferon-γ enzyme-linked immunosorbent spot (ELISPOT) assay for the sensitive detection of VZV-reactive T cells at the single-cell level ex vivo. We used this assay to monitor the frequency of VZV-reactive T cells in 17 seropositive patients during the first year after T cell–depleted allo-HSCT. The patients did not receive anti-herpesvirus prophylaxis after stem cell engraftment. Independent of the magnitude of transferred d…

Treatment with an Allogeneic Leukemia-Derived Dendritic Cell Vaccine in AML Patients Shows MRD Conversion and Improved Survival

Abstract Background. Persistence of measurable residual disease (MRD) is a poor prognostic factor and predicts relapse in acute myeloid leukemia (AML). In a phase I study, the allogeneic leukemia-derived dendritic cell vaccine, DCP-001, has shown safety and humoral and cellular immune responses (A.A. van de Loosdrecht, et al. Cancer Immunol. Immunother. 2018;67:1505). In the current phase II study, (Clintrials.gov: NCT03697707) we report on progress and evaluation of MRD conversion, as primary endpoint, relapse free and overall survival. Methods. AML-patients, ineligible at screening for HSCT, who are in first complete remission (CR1) but with MRD receive 4 biweekly doses of 25e6 or 50e6 ce…

OR26. Investigating the impact of patient’s non-shared HLA-C Allotype expression levels in A 9/10 Single HLA-C mismatched hematopoieticstem cell transplantationsetting using two different HLA-C Expression proxy models

Aim Petersdorf et al. reported in 2014 an association between patient high expressed HLA-C (C) allotypes and inferior HSCT outcome using an imputed C-expression model (Apps et al., 2013). This study aims at: a) examining the validity of Apps et al. model in Caucasians by using the same methodology in a sample of 400 healthy German blood donors. b) specifically investigating the effect of patient’s non-shared (PNS) C expression levels on outcome by applying C expression imputed data in a 9/10 HLA C-mismatched HSCT setting. Methods Buffy coats from 400 healthy German blood donors were tested by flow cytometry as previously described (Apps et al., 2013) in order to determine C expression on ly…

Impact of Prophylactic CD8-Depleted Donor-Lymphocyte Infusions After Allogeneic Hematopoietic Stem Cell Transplantation and Alemtuzumab Mediated T-Cell Depletion,

Abstract Abstract 4109 We have previously demonstrated that the application of CD8-depleted donor-lymphocyte infusions (DLI) is feasible after reduced-intensity conditioning and in vivo T-cell depletion by alemtuzumab. DLI overcome slow lymphocyte recovery associated with alemtuzumab-administration and improve anti-infectious immunity and reliably convert a decreasing T-cell chimerism (Meyer et al. Blood 2007 & BMT 2010). Here we provide clinical follow up data of 117 patients with different hematological diseases and a median observation time of 1 year (range, 1–86 months) post hematopoietic stem cell transplantation (HSCT). The majority of patients either suffered from an acute leukem…

Impact of Donor Activating KIR Genes on HSCT Outcome in C1-Ligand Negative Myeloid Disease Patients Transplanted with Unrelated Donors-A Retrospective Study.

Natural Killer cells (NK) are lymphocytes with the potential to recognize and lyse cells which escaped T-cell mediated lysis due to their aberrant HLA expression profiles. Killer cell immunoglobulin-like receptors (KIR) influence NK-cell activity by mediation of activating or inhibitory signals upon interaction with HLA-C (C1, C2) ligands. Therefore, absence of ligands for donor inhibitory KIRs following hematopoietic stem cell transplantation (HSCT) may have an influence on its outcome. Previous studies showed that C1 negative patients have a decreased HSCT outcome. Our study, based on a cohort of 200 C1-negative patients, confirmed these findings for the endpoints: overall survival (OS: H…

Immunohistochemical markers for histopathological diagnosis and differentiation of acute cutaneous graft‐versus‐host disease

Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to …

Increased age-associated mortality risk in HLA-mismatched hematopoietic stem cell transplantation.

We investigated a possible interaction between age-associated risk and HLA-mismatch associated risk on prognosis in different age categories of recipients of unrelated hematopoietic stem cell transplants (HSCT) (n=3019). Patients over 55 years of age transplanted with 8/10 donors showed a mortality risk of 2.27 (CI 1.70–3.03, P<0.001) and 3.48 (CI 2.49–4.86, P<0.001) when compared to 10/10 matched patients in the same age group and to 10/10 matched patients aged 18–35 years, respectively. Compared to 10/10 matched transplantations within each age category, the Hazards Ratio for 8/10 matched transplantation was 1.14, 1.40 and 2.27 in patients aged 18–35 years, 36–55 and above 55 years. Model…

Donor Genetic Determinant of Thymopoiesis rs2204985 Impacts Clinical Outcome after Single HLA Mismatched HSCT

Abstract Introduction: A common genetic variant within the TCRA-TCRD locus has been recently identified as a predictive factor of thymic function and T cell repertoire diversity (Clave et al., 2018). Specifically it was shown in a mouse model that transplantation of rs2204985 AA human hematopoietic stem cells (HSC) into immunodeficient mice led to lower thymocyte counts and poorer TCR diversity. T cell mediated pathways are known to play a significant role in immunological processes affecting HSCT outcome like GvL, GvH and infection. Aim of this study was to investigate the potential impact of donor rs2204985 genotype on patient's outcome after unrelated HSCT. Methods: The study included 2,…

Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation.

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n…

Human leukocyte antigen-E mismatch is associated with better hematopoietic stem cell transplantation outcome in acute leukemia patients

The immunomodulatory role of human leukocyte antigen (HLA)-E in hematopoietic stem cell transplantation (HSCT) has not been extensively investigated. To this end, we genotyped 509 10/10 HLA unrelated transplant pairs for HLA-E, in order to study the effect of HLA-E as a natural killer (NK)-alloreactivity mediator on HSCT outcome in an acute leukemia (AL) setting. Overall survival (OS), disease free survival (DFS), relapse incidence (RI) and non-relapse mortality (NRM) were set as endpoints. Analysis of our data revealed a significant correlation between HLA-E mismatch and improved HSCT outcome, as shown by both univariate (53% vs. 38%, P=0.002, 5-year OS) and multivariate (hazard ratio (HR)…

The Impact of NFAT Inhibition on Neutrophil Effector Functions in Patients after Allogeneic Hematopoietic Stem Cell Transplantation and on Neutrophil Antifungal Defense and Myelopoiesis in Cyclosporin Α Treated and NFATc1LysM Mice

Abstract Background and Aims: Immunosuppressive medication e.g. by calcineurin inhibitors substantially contributes to the risk for opportunistic fungal infections in patients after allogeneic transplantation (HSCT). It is well known that the nuclear factor of activated T cells (NFAT) is an important transcription factor downstream of calcineurin especially in T cells. Additionally, recent data in rodent models indicate that NFAT also seems to play a relevant role in innate antifungal immune responses by polymorphonuclear neutrophils (PMN), as well as in regulation of myelopoiesis and myeloid differentiation. Methods: Firstly, isolated PMN from healthy donors were analyzed in vitro in absen…

Treatment of Newly Diagnosed Moderate or Severe Chronic Graft-Versus-Host Disease with Prednisone and Everolimus (PredEver first): A Prospective Multicenter Phase IIa Study

Background Chronic graft-versus-host disease (cGVHD) is the major cause of treatment related morbidity and mortality after allogeneic stem cell transplantation (allo-HSCT). Recently Paul Martin et al. reported that treatment success at 1 year (defined as a patient being in partial (PR) or complete remission (CR) of cGVHD, in ongoing remission of underlying disease and not requiring any secondary treatment for cGVHD) was the only endpoint associated with clinical benefit. Strikingly this robust endpoint was only achieved in less than 20% of patients undergoing primary treatment for cGVHD. Therefore, although most patients show initial response to first-line therapy, long-term clinically mean…