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Der vorliegende 4. deutsche Konsensus zur immungenetischen Spenderauswahl fur die allogene Stammzelltransplantation wurde von der Deutschen Gesellschaft fur Immungenetik (DGI) und der Deutschen Arbeitsgemeinschaft fur Knochenmark- und Blutstammzelltransplantation (DAG-KBT) gemeinsam erarbeitet und verabschiedet. Er stellt den gemeinsamen Nenner von mehr als 60 Transplantationseinheiten und fast 20 immungenetischen Sucheinheiten dar, die mehr als 3000 deutsche Patienten jahrlich betreuen. Wahrend der 1. Konsensus im Jahre 1996 den Anfang der Ablosung von zellularen und serologischen Methoden der HLA-Testung durch molekulargenetische Verfahren darstellte, wird nun die hochaufgeloste Bestimmung der Antigenbindungsstelle der HLA-Molekule der 5 wichtigsten Genorte als Standard definiert. Das vorliegende Dokument behandelt die Suche nach verwandten und nicht-verwandten Spendern und alle infrage kommenden Stammzellquellen. Bei Sachverhalten, fur die eine eindeutig wissenschaftliche Evidenz vorliegt, gibt dieser Konsensus eine klare Richtschnur vor, wahrend es sonst, soweit moglich, die Handlungsoptionen beschreibt.

SummaryAtg16L1 mediates the cellular degradative process of autophagy and is considered a critical regulator of inflammation based on its genetic association with inflammatory bowel disease. Here we find that Atg16L1 deficiency leads to an exacerbated graft-versus-host disease (GVHD) in a mouse model of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Atg16L1-deficient allo-HSCT recipients with GVHD displayed increased T cell proliferation due to increased dendritic cell (DC) numbers and costimulatory molecule expression. Reduced autophagy within DCs was associated with lysosomal abnormalities and decreased amounts of A20, a negative regulator of DC activation. These results broaden the function of Atg16L1 and the autophagy pathway to include a role in limiting a DC-mediated response during inflammatory disease, such as GVHD.

A putative involvement of the vasculature seems to play a critical role in the pathophysiology of graft-versus-host disease (GVHD). We aimed to characterize alterations of mesenteric resistance arteries in GVHD in a fully MHC-mismatched model of BALB/c mice conditioned with total body irradiation that underwent transplantation with bone marrow cells and splenocytes from syngeneic (BALB/c) or allogeneic (C57BL/6) donors. After 4 weeks, animals were sacrificed and mesenteric resistance arteries were studied in a pressurized myograph. The expression of endothelial (eNOS) and inducible nitric oxide (NO)–synthase (iNOS) was quantified and vessel wall ultrastructure was investigated with electron microscopy. The myograph study revealed an endothelial dysfunction in allogeneic-transplant recipients, whereas endothelium-independent vasodilation was similar to syngeneic-transplant recipients or untreated controls. The expression of eNOS was decreased and iNOS increased, possibly contributing to endothelial dysfunction. Additionally, arteries of allogeneic transplant recipients exhibited a geometry-independent increase in vessels strain. For both findings, electron microscopy provided a structural correlate by showing severe damage of the whole vessel wall in allogeneic-transplant recipient animals. Our study provides further data to prove, and is the first to characterize, functional and structural vascular alterations in the early course after allogeneic transplantation directly in an ex vivo setting and, therefore, strongly supports the hypothesis of a vascular form of GVHD.

Next-generation sequencing of the hypervariable V3 region of the 16s rRNA gene isolated from serial stool specimens collected from 31 patients receiving allogeneic stem cell transplantation (SCT) was performed to elucidate variations in the composition of the intestinal microbiome in the course of allogeneic SCT. Metagenomic analysis was complemented by strain-specific enterococcal PCR and indirect assessment of bacterial load by liquid chromatography-tandem mass spectrometry of urinary indoxyl sulfate. At the time of admission, patients showed a predominance of commensal bacteria. After transplantation, a relative shift toward enterococci was observed, which was more pronounced under antibiotic prophylaxis and treatment of neutropenic infections. The shift was particularly prominent in patients that developed subsequently or suffered from active gastrointestinal (GI) graft-versus-host disease (GVHD). The mean proportion of enterococci in post-transplant stool specimens was 21% in patients who did not develop GI GVHD as compared with 46% in those that subsequently developed GI GVHD and 74% at the time of active GVHD. Enterococcal PCR confirmed predominance of Enterococcus faecium or both E. faecium and Enterococcus faecalis in these specimens. As a consequence of the loss of bacterial diversity, mean urinary indoxyl sulfate levels dropped from 42.5 ± 11 μmol/L to 11.8 ± 2.8 μmol/L in all post-transplant samples and to 3.5 ± 3 μmol/L in samples from patients with active GVHD. Our study reveals major microbiome shifts in the course of allogeneic SCT that occur in the period of antibiotic treatment but are more prominent in association with GI GVHD. Our data indicate early microbiome shifts and a loss of diversity of the intestinal microbiome that may affect intestinal inflammation in the setting of allogeneic SCT.

Introduction Myeloproliferative Neoplasm (MPN) unclassifiable (MPN-U), is a heterogeneous disease that presents with an MPN-type clinical/ histological phenotype yet fails to meet diagnostic criteria for other MPN entities. Incidence is Methods This registry-based analysis was approved by the Chronic Malignancies Working Party of the EBMT. Patient selection was performed by identifying adult patients who underwent first allo-HCT for MPN-U between 2000-2015, using either Reduced Intensity Conditioning (RIC) or Myeloablative conditioning (MAC) as defined by standard EBMT criteria. Further data collection requests (MED-C) forms were sent to centres to improve data completeness. Statistical analyses were performed with SPSS 22 (SPSS Inc./IBM, Armonk, NY) and R. Overall Survival (OS) was calculated from the date of transplant until death or last observation alive. Cumulative incidence functions were used to estimate Non-Relapse Mortality (NRM) and Relapse Incidence (RI) within a competing risk setting. Results A total of 70 patients, 48 (69%) male and 22 (31%) female, with a confirmed diagnosis of MPN-U were analysed. Median age was 57 years (range (r), 22-70 years). Of these patients, 37 (53%) underwent allo-HCT in the period 2001-2010 and 33 (47%) between 2011-2015. MAC regimens were utilised in 31 (44%) patients while 39 (56%) received RIC. Patients were most frequently transplanted within the first two years from diagnosis, with a median time to allo-HCT of 13 months (r, 3-244 months). Diagnostic karyotype was normal in 36 (51%) and abnormal in 23 (33%) patients, with data missing for 11 (16%) patients. A total of 45 (64%) patients had received prior treatment, 23 (33%) patients were untreated and data was incomplete in 2 (3%) patients. Regarding donor type, 27 (39%) patients had a Matched Sibling Donor (MSD) and 43 (61%) an Unrelated Donor (URD). Most frequent conditioning regimens were TBI-based in the MAC cohort and Fludarabine-Busulphan in the RIC cohort. A trend towards higher rates of delayed/failed engraftment was noted in the RIC compared to MAC cohort (p=0.09). Where successful, median time to neutrophil engraftment in both cohorts was similar (18 days for MAC and 17 for RIC) and both platforms demonstrated similar platelet engraftment times (17.5 days). Incidence of grade II-IV aGVHD at 3 months was higher in the MAC (37%) compared to RIC cohort (16%; p=0.05) and the 12-month cumulative incidence of cGVHD for MAC was 52% (95%CI: 32.4, 71.6) and for RIC 32.1% (95%CI: 14.8, 49.4; p=0.117)). Median follow-up was 87 months (minimum and maximum of censored cases: 31 and 196 months). The median OS estimates at 1, 3 and 5-year were 77%, 55% and 42% (MAC) and 59%, 44% and 41% (RIC), respectively (p=0.33). No significant difference existed in OS rates between those who had pre-transplant therapy versus not. Relapse remained significant: cumulative incidences of relapse at 1,3 and 5-years were 10%, 23% and 27% (MAC) and 28%, 36% and 36% (RIC), respectively (p=0.28). NRM probabilities at 1, 3 and 5-years post allo-HCT were also considerable: 19%, 29%, and 34% (MAC) and 28%, 28% and 28% (RIC), respectively (p=0.84). Main causes of NRM were infection and GVHD. Univariate analysis associated use of an URD with a significantly worse OS and NRM compared with MSD. Moreover, the presence of abnormal karyotype at time of allo-HCT was associated with a trend towards a higher risk of relapse (p=0.06). Conclusions This study highlights the potentially curative role of allo-HCT in MPN-U and provides clinicians with robust engraftment, GVHD and outcome data. Both engraftment and OS rates appear acceptable yet NRM and CIR rates in both settings remain high and need to be addressed. The impact of abnormal karyotype at the time of allo-HCT and a trend towards higher risks of relapse requires further elucidation. Disclosures McLornan: Novartis: Honoraria; Jazz Pharmaceuticals: Honoraria, Speakers Bureau. Robin:Novartis Neovii: Research Funding. Chalandon:Novartis: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Incyte Biosciences: Consultancy, Honoraria. Beelen:Medac GmbH Wedel Germany: Consultancy, Honoraria. Kröger:Sanofi-Aventis: Honoraria; Riemser: Research Funding; Novartis: Honoraria, Research Funding; Neovii: Honoraria, Research Funding; Medac: Honoraria; JAZZ: Honoraria; DKMS: Research Funding; Celgene: Honoraria, Research Funding. Milojkovic:Novartis: Honoraria, Speakers Bureau; Incyte: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau. Hernandez Boluda:Incyte: Other: Travel expenses paid.

7015 Background: Relationships between microbiota composition and clinical outcomes following allogeneic hematopoietic cell transplantation (allo-HCT) have been described in single-center studies. Geographic variations in human microbial communities and differences in clinical practices across institutions raise the question of whether these associations are generalizable. We report the first multi-center study of the intestinal microbiota in allo-HCT. Methods: Intestinal communities in 8,768 fecal samples from 1,362 allo-HCT patients at 4 centers on 3 continents were profiled by 16S sequencing. Associations between microbiota composition and clinical outcomes were analyzed with proportional-hazards analysis in an observational study. Results: We observed reproducible patterns of microbiota injury characterized by loss of diversity and domination by single taxa. Low diversity in the neutrophil engraftment period was reproducibly associated with increased risk of death (multivariate HR 0.48 [0.30-0.77] p = 0.002 in the largest cohort). These reductions in OS were in part due to an increased risk of transplant-related mortality and graft-vs-host disease. Baseline pre-HCT samples already bore evidence of microbiome disruption; low diversity prior to transplantation was associated with poor survival. A bacterial-composition risk score that was trained in one cohort predicted mortality in the other three cohorts (multivariate HR 1.42 [1.04-1.93] p = 0.03), indicating that not only a diversity metric but also a signature of specific bacterial abundances is informative about post-HCT mortality risk across independent institutions. Conclusions: We demonstrate a relationship between microbiota and survival after allo-HCT that is independent of transplant center and geographic location. The diversity of clinical practices across institutions imposed significant heterogeneity in the study, yet we observed reproducible microbiota injury patterns and associations with outcomes. This concordance suggests that approaches to manipulate the intestinal microbiota in allo-HCT may be generalizable.

Background Allogeneic hematopoietic stem cell transplantation (HCT) remains a challenge in elderly and comorbid AML and MDS patients. This patient population is at increased risk for non-relapse mortality (NRM) when treated with standard myeloablative conditioning and was selected to compare a newly developed treosulfan-based with a well-established reduced intensity busulfan-based preparative regimen in a prospective randomized clinical phase III trial. Methods Adult patients with AML in remission or MDS scheduled for HCT from matched related or unrelated donors, aged ≥50 years or with a comorbidity index (HCT-CI) of >2 were enrolled by a central stratified randomization procedure. Treatment arms consisted of intravenous (IV) treosulfan (10 g/m²/day [d-4 to d-2]) or IV busulfan (3.2 mg/kg/day [d-4 to d-3]), both combined with IV fludarabine (30 mg/m²/day [d-6 to d-2]). The primary objective was to compare event-free survival (EFS) at two years with relapse/progression of disease, graft failure, or death reported as events. Secondary endpoints were safety evaluation (according to CTCAE v4.03), engraftment, chimerism, overall survival (OS), relapse/progression incidence (RI), NRM and acute or chronic GvHD. After a previously conducted confirmatory interim analysis (based on 476 patients), which resulted in early termination of patient accrual due to significant non-inferiority of treosulfan treatment with improved EFS, NRM and OS (Beelen et al., ASH 2017), results of the final analysis of all 570 randomized patients including post surveillance data are provided here. Results Median age of the 551 patients (352 AML; 199 MDS) included in the full analysis set (268 treosulfan; 283 busulfan) was 60 years (range: 31, 70). Frequencies of early adverse events (d-6 to d+28) and incidences of acute and chronic GvHD were largely comparable between the two regimens, while extensive chronic GvHD was numerically in favor of treosulfan (19.7% vs. 26.7%; p=0.0750). Primary neutrophil recovery at day +28 was comparable, while the rate of complete donor-type chimerism (day +28) was higher after treosulfan (93.2% vs. 83.3%; p Conclusions Final evaluation of this phase III trial substantiates the previous confirmatory analysis resulting in significantly improved survival after treosulfan-based conditioning. Due to the reduction of NRM a major clinical benefit of the new treosulfan conditioning regimen was demonstrated in the selected AML/MDS patient population.

Intestinal microbiota composition is associated with important allo-HCT outcomes including relapse, GVHD, immune reconstitution, and infections. Intestinal diversity assessed peri-neutrophil-engraftment is predictive of TRM and overall survival. These observations were made in single-center studies of post-HCT stool samples. We hypothesized that the pre-HCT microbiota is also a determinant of post-HCT outcomes. 1,922 stool samples were collected ∼weekly from 991 allo-HCT pts at 4 centers (Cohorts 1 and 2 in the US; cohort 3 in Europe; cohort 4 in Japan). The patients varied in diagnosis, graft sources, and conditioning intensity. All samples were 16S sequenced and analyzed at a central lab. Pre-HCT a-diversity (inverse Simpson) values in 4 cohorts were 1.7-to-2.5-fold lower than those of healthy volunteers (A, p We next asked how similar these pre-HCT communities are across geography. Bray-Curtis distances between cohorts were much smaller than the changes observed over time during transplantation (C, p To better characterize these low-diversity phenotypes, we defined domination as a microbiota injury in which any taxon comprised >30% of bacterial abundance. The dominating taxa belonged to multiple genera, most commonly Enterococcus (E). In all 4 cohorts, the cumulative incidence of monodomination was >50% by d+0 and >87% by d+28 (Fig F). In the largest cohort, low-diversity states were associated with exposure to broad-spectrum antibiotics, conditioning intensity, and low calorie intake. In conclusion, we demonstrate that allo-HCT pts from 4 institutions on 3 continents presented with pre-HCT microbiota configurations that were similar to one another and distinct from those of healthy individuals. Severe microbiota injury as revealed by domination is a common event that begins before allograft infusion, and pre-HCT microbiota injury predicts poor overall survival. These observations suggest the pre-HCT period as a window of opportunity to (a) assess microbiota injury as part of comorbidity evaluation, (b) inform selection of antibiotic prophylaxis, gut-decontamination, GVHD-prophylaxis, or conditioning regimens, and (c) intervene with microbiota injury-remediation or prevention strategies.

Item does not contain fulltext GVHD remains the major impediment to broader application of allogeneic haematopoietic SCT. It can be prevented completely, but at the expense of other complications, rejection, relapse or delayed immune reconstitution. No optimal prevention or treatment method has been defined. This is reflected by enormous heterogeneity in approaches in Europe. Retrospective comparisons between different policies, although warranted, do not give definite answers. In order to improve the present situation, an European Group for Blood and Marrow Transplantation and the European LeukemiaNet working group has developed in a Delphi-like approach recommendations for prophylaxis and treatment of GVHD in the most common allogeneic transplant setting, transplantation from an HLA-identical sibling or unrelated donor for standard risk malignant disease. The working group proposes these guidelines to be adopted as routine standard in transplantation centres and to be used as comparator in systematic studies evaluating the advantages and disadvantages of practices differing from these recommendations.

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Single nucleotide polymorphisms (SNPs) have been associated with an increased incidence of invasive aspergillosis (IA) after allogeneic stem cell transplantation (allo-SCT). We analyzed 41 patients with proven/probable IA after allo-SCT for an association of SNPs, within the TLR2, TLR4, TLR5, TLR9, and NOD2/CARD15 genes, with susceptibility to IA. The control group consisted of 130 patients who had allo-SCT but did not develop IA. While no association was found for donor SNPs and the recipients’ risk of IA, analysis of recipient SNPs showed a significant association between the presence of recipient TLR5-Stop SNP (1174C> T) and the incidence of IA (P = 0.004). Multivariate analysis demonstrated that the recipient TLR5-Stop SNP appeared as an independent risk factor for IA after allo-SCT. Our study suggests that TLR5 is involved in host defense against Aspergillus fumigatus, and that the recipient TLR5-Stop SNP represents a risk factor for the development of IA after allo-SCT.

Eosinophilia after allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been associated with the development of acute and chronic graft-versus-host disease (cGVHD). However, a limited number of studies have investigated the course of eosinophil counts in relation to the onset of cGVHD. In this study, the course of relative eosinophil counts (RECs) was retrospectively analyzed in 64 patients who developed cGVHD following allogeneic HSCT in relation to overall survival (OS), relapse rate and clinical course of cGVHD. At onset of cGVHD, eosinophilia was observed in 45% of the patients and developed one week prior to cGVHD diagnosis. Furthermore, a trend towards improved OS in patients with eosinophilia was observed. Beneficial effects were most evident in patients who exhibited decreasing eosinophil counts one week after diagnosis of cGVHD. By contrast, an increase in or stable eosinophil counts one week after diagnosis were associated with significantly impaired OS and a significantly higher rate of later aggravation of cGVHD. Findings of this study suggested that the course of eosinophil counts may provide a useful parameter in the assessment of cGVHD development and activity allowing the potential identification of patient subpopulations with a good outcome and reduced cGVHD-related mortality.

Allogeneic hematopoietic stem cell transplantation is one curative treatment for hematological malignancies, but is compromised by life-threatening complications, such as severe acute graft-versus-host disease (aGvHD). Prediction of severe aGvHD as early as possible is crucial to allow timely initiation of treatment. Here we report on a multicentre validation of an aGvHD-specific urinary proteomic classifier (aGvHD_MS17) in 423 patients. Samples (n=1106) were collected prospectively between day +7 and day +130 and analyzed using capillary electrophoresis coupled on-line to mass spectrometry. Integration of aGvHD_MS17 analysis with demographic and clinical variables using a logistic regression model led to correct classification of patients developing severe aGvHD 14 days before any clinical signs with 82.4% sensitivity and 77.3% specificity. Multivariate regression analysis showed that aGvHD_MS17 positivity was the only strong predictor for aGvHD grade III or IV (P

Background Primary refractory acute myeloid leukemia (PRF-AML) is associated with a dismal prognosis. Allogeneic stem cell transplantation (HSCT) in active disease is an alternative therapeutic strategy. The increased availability of unrelated donors together with the significant reduction in transplant-related mortality in recent years have opened the possibility for transplantation to a larger number of patients with PRF-AML. Moreover, transplant from unrelated donors may be associated with stronger graft-mediated anti-leukemic effect in comparison to transplantations from HLA-matched sibling donor, which may be of importance in the setting of PRF-AML. Methods The current study aimed to address the issue of HSCT for PRF-AML and to compare the outcomes of HSCT from matched sibling donors (n = 660) versus unrelated donors (n = 381), for patients with PRF-AML between 2000 and 2013. The Kaplan-Meier estimator, the cumulative incidence function, and Cox proportional hazards regression models were used where appropriate. Results HSCT provide patients with PRF-AML a 2-year leukemia-free survival and overall survival of about 25 and 30%, respectively. In multivariate analysis, two predictive factors, cytogenetics and time from diagnosis to transplant, were associated with lower leukemia-free survival, whereas Karnofsky performance status at transplant ≥90% was associated with better leukemia-free survival (LFS). Concerning relapse incidence, cytogenetics and time from diagnosis to transplant were associated with increased relapse. Reduced intensity conditioning regimen was the only factor associated with lower non-relapse mortality. Conclusions HSCT was able to rescue about one quarter of the patients with PRF-AML. The donor type did not have any impact on PRF patients’ outcomes. In contrast, time to transplant was a major prognostic factor for LFS. For patients with PRF-AML who do not have a matched sibling donor, HSCT from an unrelated donor is a suitable option, and therefore, initiation of an early search for allocating a suitable donor is indicated. Electronic supplementary material The online version of this article (doi:10.1186/s13045-017-0498-8) contains supplementary material, which is available to authorized users.

One of the major challenges of allogeneic stem cell transplantation (allo-SCT) is to reduce the risk of graft-versus-host disease (GVHD) while boosting the graft-versus-leukemia (GVL) effect. The reconstitution of natural killer (NK) cells following allo-SCT is of notable interest due to their known capability to induce GVL without GVHD. Here, in this study, we investigate the association between the incidence and severity of acute graft-versus-host disease (aGVHD) and the early reconstitution of NK cell subsets following allo-SCT. We analyzed 342 samples from 107 patients using flow cytometry, with a focus on immature CD56high and mature cytotoxic CD56dim NK cells. Longitudinal analysis of immune reconstitution after allo-SCT showed that the incidence of aGVHD was associated with a delayed expansion of the entire NK cell population, in particular the CD56high subset. Notably, the disturbed reconstitution of the CD56high NK cells also correlated with the severity of aGVHD.

Antithymocyte globulin (ATG) is used in the prevention of graft-versus-host disease during allogeneic hematopoietic stem cell transplantation. It is generally accepted that ATG mediates its immunosuppressive effect primarily via depletion of T cells. Here, we analyzed the impact of ATG-Fresenius (now Grafalon (R)) on human monocyte-derived dendritic cells (DC). ATG induced a semi-mature phenotype in DC with significantly reduced expression of CD14, increased expression of HLA-DR, and intermediate expression of CD54, CD80, CD83, and CD86. ATG-DC showed an increase in IL-10 secretion but no IL-12 production. In line with this tolerogenic phenotype, ATG caused a significant induction of indoleamine 2,3-dioxygenase expression and a concomitant increase in levels of tryptophan metabolites in the supernatants of DC. Further, ATG-DC did not induce the proliferation of allogeneic T cells in a mixed lymphocyte reaction but actively suppressed the T cell proliferation induced by mature DC. These data suggest that besides its well-known effect on T cells, ATG modulates the phenotype of DC in a tolerogenic way, which might constitute an essential part of its immunosuppressive action in vivo.

In allogeneic stem cell transplantation (ASCT), systemic broad-spectrum antibiotics are frequently used for treatment of infectious complications, but their effect on microbiota composition is still poorly understood. This retrospective analysis of 621 patients who underwent ASCT at the University Medical Center of Regensburg and Memorial Sloan Kettering Cancer Center in New York assessed the impact of timing of peritransplant antibiotic treatment on intestinal microbiota composition as well as transplant-related mortality (TRM) and overall survival. Early exposure to antibiotics was associated with lower urinary 3-indoxyl sulfate levels (P .001) and a decrease in fecal abundance of commensal Clostridiales (P = .03) compared with late antibiotic treatment, which was particularly significant (P = .005) for Clostridium cluster XIVa in the Regensburg group. Earlier antibiotic treatment before ASCT was further associated with a higher TRM (34%, 79/236) compared with post-ASCT (21%, 62/297, P = .001) or no antibiotics (7%, 6/88, P .001). Timing of antibiotic treatment was the dominant independent risk factor for TRM (HR, 2.0; P ≤ .001) in multivariate analysis besides increase age (HR, 2.15; P = .004), reduced Karnofsky performance status (HR, 1.47; P = .03), and female donor-male recipient sex combination (HR, 1.56; P = .02) A competing risk analysis revealed the independent effect of early initiation of antibiotics on graft-versus-host disease-related TRM (P = .004) in contrast to infection-related TRM and relapse (not significant). The poor outcome associated with early administration of antibiotic therapy that is active against commensal organisms, and specifically the possibly protective Clostridiales, calls for the use of Clostridiales-sparing antibiotics and rapid restoration of microbiota diversity after cessation of antibiotic treatment.

ABO blood group antigen incompatibility (ABO mismatch) is not an obstacle to allogeneic stem cell transplantation (allo-SCT). However, the impact on clinical outcome after allo-SCT remains controversial. We analyzed 512 patients after allogeneic peripheral blood SCT (allo-PBSCT) for an association of ABO mismatch with transfusion requirements, myeloid and platelet engraftment, the incidence of GvHD, relapse, transplant-related mortality (TRM), and overall survival (OS). A total of 260 patients underwent ABO-mismatched transplantation and the control group consisted of 252 patients with ABO-matched allo-PBSCT. We found a significant association between major-0 ABO mismatch (group 0 recipient/group A, B, or AB donor) and increased red blood cell (RBC) and platelet transfusion requirements (both P

For over 60 years, hematopoietic stem cell transplantation has been the major curative therapy for several hematological and genetic disorders, but its efficacy is limited by the secondary disease called graft versus host disease (GvHD). Huge advances have been made in successful transplantation in order to improve patient quality of life, and yet, complete success is hard to achieve. This review assimilates recent updates on pathophysiology of GvHD, prophylaxis and treatment of GvHD-related complications, and advances in the potential treatment of GvHD.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the main curative therapy for hematological malignancy such as leukemias, lymphomas, or multiple myelomas and some other hematological disorders. In this therapy, cure of hematological diseases relies on graft-versus-malignancy effects by allogenic immune cells. However, severe posttransplant treatment-associated complications such as acute graft-versus-host disease (aGvHD) and chronic graft-versus-host disease (cGvHD) limit this approach. Most research into GvHD has concentrated on the aGvHD, while the more complex and multifaceted chronic form has been largely poorly investigated. cGvHD is a multi-organ autoimmune disorder and is the major cause of non-relapse morbidity and mortality following allo-HSCT, occurring in about 50% of patients, or 13,000–15,000 patients per year worldwide. Therefore, there is a high medical need for an early prediction of these therapy-associated toxicities. Biomarkers have gained importance over the last decade in diagnosis, in prognosis, and in prediction of pending diseases or side effects. Biomarkers can be cells, factors isolated from target tissues, or soluble factors that can be detected in body fluids. In this review, we aim to summarize some of the recent developments of biomarkers in the field of allo-HSCT. We will focus on cell-based biomarkers (B-cell subsets) for cGvHD and soluble factors including microRNA (miRNA), which are excreted into serum/plasma and urine. We also discuss the potential role of cytosolic and extracellular 70 kDa heat shock proteins (HSP70) as potential biomarkers for aGvHD and their role in preclinical models. Proteomic biomarkers in the blood have been used as predictors of treatment responses in patients with aGvHD for many years. More recently, miRNAs have been found to serve as a biomarker to diagnose aGvHD in the plasma. Another development relates to urine-based biomarkers that are usually detected by capillary electrophoresis and mass spectrometry. These biomarkers have the potential to predict the development of severe aGvHD (grades III–IV), overall mortality, and the pending development of cGvHD in patients posttransplant.

The integrity of the vasculature plays an important role in the success ofallogeneic organ and haematopoietic stem cell transplantation. Endothelial cells(EC) have previously been shown to be the target of activated cytotoxic Tlymphocytes (CTL) resulting in extensive cell lysis. Mesenchymal stromal cells(MSC) are multipotent cells which can be isolated from multiple sites, eachdemonstrating immunomodul atory capabilities. They are explored herein fortheir potential to protect EC from CTL-targeted lys is. CD8+T cells isolated fromhuman PBMC were stimulated with mitotically inactive cells of a humanmicrovascular endothelial cell line (CDC/EU.HMEC-1, further referred to asHMEC) for 7 days. Target HMEC were cultured in the presence or absence ofMSC for 24 h before exposure to activated allogeneic CTL for 4 h. EC were thenanalysed for cytotoxic lysis by flow cytometry. Culture of HMEC with MSC inthe efferent immune phase (24 h before the assay) led to a decrease in HMEClysis. This lysis was determined to be MHC Class I restricted linked and furtheranalysis suggested that MSC contact is important in abrogation of lysis, asprotection is reduced where MSC are separated in transwell experiments. Theefficacy of multiple sources of MSC was also confirmed, and the collaborativeeffect of MSC and the endothelium protective drug defibrotide were determined,with defibrotide enhancing the protection provided by MSC. These resultssupport the use of MSC as an adjuvant cellular therapeutic in transplantmedicine, alone or in conjunction with EC protective agents such as defibrotide. Science Foundation Ireland Bayerische Forschungsstiftung (Bavarian Research Foundation) Wilhelm Sander Foundation Servier Laboratories

Motivation In biomedicine, every molecular measurement is relative to a reference point, like a fixed aliquot of RNA extracted from a tissue, a defined number of blood cells, or a defined volume of biofluid. Reference points are often chosen for practical reasons. For example, we might want to assess the metabolome of a diseased organ but can only measure metabolites in blood or urine. In this case, the observable data only indirectly reflects the disease state. The statistical implications of these discrepancies in reference points have not yet been discussed. Results Here, we show that reference point discrepancies compromise the performance of regression models like the LASSO. As an alternative, we suggest zero-sum regression for a reference point insensitive analysis. We show that zero-sum regression is superior to the LASSO in case of a poor choice of reference point both in simulations and in an application that integrates intestinal microbiome analysis with metabolomics. Moreover, we describe a novel coordinate descent based algorithm to fit zero-sum elastic nets. Availability and Implementation The R-package “zeroSum” can be downloaded at https://github.com/rehbergT/zeroSum. Moreover, we provide all R-scripts and data used to produce the results of this manuscript as Supplementary Material. Supplementary information Supplementary material is available at Bioinformatics online.

Summary The EBMT risk score is an established tool successfully used in the prognosis of survival post-HSCT and is applicable for a range of haematological disorders. One of its main advantages is that score generation involves summation of clinical parameters that are available pretransplant. However, the EBMT risk score is recognized as not being optimal. Previous analyses, involving patients with various diagnoses, have shown that non-HLA gene polymorphisms influence outcome after allogeneic HSCT. This study is novel as it focuses only on patients having acute leukaemia (N = 458) and attempts to demonstrate how non-HLA gene polymorphisms can be added to the EBMT risk score in a Cox regression model to improve prognostic ability for overall survival. The results of the study found that three genetic factors improved EBMT risk score. The presence of MAL (rs8177374) allele T in the patient, absence of glucocorticoid receptor haplotype (consisting of rs6198, rs33389 and rs33388) ACT in the patient and absence of heat-shock protein 70-hom (+2437) (rs2227956) allele C in the patient were associated with decreased survival time. When compared to the EBMT risk score, the scores combining EBMT risk score with the genetic factors had an improved correlation with clinical outcome and better separation of risk groups. A bootstrapping technique, involving repeated testing of a model using multiple validation sets, also revealed that the newly proposed model had improved predictive value when compared to the EBMT risk score alone. Results support the view that non-HLA polymorphisms could be useful for pretransplant clinical assessment and provide evidence that polymorphisms in the recipient genotype may influence incoming donor cells, suppressing the initiation of the graft versus leukaemia effect and reducing survival.

We analyzed lymphocyte subpopulations and cytokines 3 months after allogeneic hematopoietic stem cell transplantation aiming to identify predictive cellular and serum markers for chronic graft-versus-host disease (cGVHD). Samples of 49 patients (pts) (no cGVHD (n = 14), subsequent quiescent onset (n = 16), de novo onset of cGVHD (n = 19)) were analyzed in the absence of active GVHD by flow cytometry and enzyme-linked immunosorbent assay. All mean absolute cell counts are presented as cells per microliter; relative cell counts are presented as percentage of lymphocytes. Pts with subsequent de novo cGVHD had significantly higher relative and absolute counts of CD4+ T cells including higher absolute counts of CD4+ memory T cells (22.36%; 206.55/μl; 136/μl, respectively) compared to pts with subsequent quiescent onset of cGVHD (12.41%; 83.42/μl; 54.3/μl) and pts without cGVHD (10.55%) with regard to relative counts of CD4+ T cells. Similarly, significantly more relative and absolute regulatory T cell numbers (CD4+FOXP3+) were detected in pts with de novo onset of cGVHD (3.08% and 24.63/μl) compared to those in pts without (1.25% and 9.06/μl) or with quiescent onset of cGVHD (1.15% and 6.91/μl). Finally, relative B cell counts, including naive and memory B cells, were also significantly decreased in pts developing quiescent cGVHD (0.85, 0.73, 0.12% resp.) when compared to pts with de novo onset (5.61, 5.24, 0.38%). The results demonstrate that alterations in immune reconstitution are already present before onset of clinical symptoms and differ between de novo and quiescent onset of disease.

Extracorporeal photopheresis (ECP) is a therapeutic technique that combines leukapheresis and ultraviolet (UV)A irradiation of the leukapheresate after 8-methoxypsoralen treatment with subsequent retransfusion. It can be achieved with a single device (online) or by combining an apheresis machine with a separate UVA light source (offline). The comparability of both established methods is unknown.In a prospective setting, four ECP systems were evaluated: one with integrated UVA irradiation for online ECP (Therakos) and three with external UVA irradiation for offline ECP (Amicus, Optia, and Cobe Spectra). Apheresis variables and cell counts were determined by methods including flow cytometry.The duration of apheresis ranged from 120 minutes (Amicus, Optia) to 275 minutes (Therakos). Mononuclear cell (MNC) counts in the treatment bags were comparable between offline ECP methods (median, 57 × 10All offline ECP systems studied yielded comparable cellular compositions and highly enriched populations of MNCs. In contrast, white blood cells from online ECP displayed enrichment of nonclassical monocytes. The relevance of these findings is unknown as there is no established biomarker to predict the therapeutic efficacy of these procedures.

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a potentially life-threatening complication of chemotherapeutic conditioning used in preparation for hematopoietic stem-cell transplantation (SCT). Defibrotide (DF) has been shown in Phase II and III trials to improve complete response in patients with severe VOD (sVOD). None of the articles, to date, provide a comprehensive review of the safety of DF in VOD and/or a range of other conditions.This article reviews current clinical findings on DF, primarily in terms of safety for use in treatment and prophylaxis of VOD, and relevant safety data for its use in other diseases. The literature review was conducted using a PubMed search with the fixed term 'defibrotide' in combination with ≥ 1 of 'safety', 'veno-occlusive disease' (with and without 'treatment', 'prevention'), 'oncology', 'myeloma', 'microangiopathy', 'anti-thrombotic' and 'peripheral vascular disorder'. Related articles from the EBMT and ASH conference websites were also included.DF was well tolerated in majority of the studies. The safety profile of DF is largely favourable with toxicities comparable to control populations in the setting of SCT complicated by sVOD.

Risk stratification criteria for patients with Ewing's sarcoma family of tumors (ESFT) are still limited. We hypothesized divergent human leukocyte antigen (HLA) patterns in ESFT patients and compared HLA-A, -B and -DR phenotype frequencies of patients with advanced ESFT with those of healthy controls.HLA types of all German Caucasian patients with advanced ESFT and available HLA-A, -B and -DR data registered in the European Group for Blood and Marrow Transplantation, Paediatric Registry for Stem Cell Transplantation and the MetaEICESS data bases (study group, n=30) were retrospectively compared with HLA types of healthy German stem cell donors (control group, n=8 862 for single HLA frequencies and n=8 839 for allele combinations). Study group patients had been immuno-typed due to eligibility for allogeneic stem cell transplantation for high risk of treatment failure, and thus constituted a selected subgroup of ESFT patients.After Bonferroni correction for multiple testing (PC), phenotype frequencies of HLA-A24 remained significantly higher in the study group compared to controls (PC

The influence of personality on health related quality of life (QoL) and physical functioning in the setting of allogeneic hematopoietic SCT (alloHSCT) is unknown. We conducted a joint evaluation within two independent cohorts of alloHSCT recipients to investigate the impact of personality on reported QoL and physical functioning. Two-hundred-eight patients (median age 44 years, range 18–72) of cohort 1 and 93 patients (median age 55 years, range 19–79) of cohort 2 after alloHSCT were evaluated. Personality was assessed using the 24-adjective measure (AM), which measures the Big-Five personality domains and the Life Orientation Test—Revised (LOT-R), measuring optimism and pessimism. QoL was measured using the Functional Assessment of Cancer Therapy with bone marrow transplantation subscale (FACT-BMT), Short Form 36 (SF-36), the human activity profile (HAP), as well as the NIH criteria-based cGVHD activity assessment form and the Lee cGVHD symptom scale. Neuroticism was significantly associated with worse function measured by the HAP and FACT-BMT. Optimism significantly improved QoL captured by the FACT-BMT. Pessimism significantly impaired physical function captured by the HAP and SF-36. Extraversion was significantly associated with reduced depression and lower severity of cGVHD symptoms reported by the patient and the physician. The results suggest that personality traits and pre-treatment QoL assessments should be measured in clinical trials to facilitate the interpretation of QoL data.

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome, is a potentially life-threatening complication of chemotherapeutic conditioning used in preparation for hematopoietic stem-cell transplantation (SCT). VOD may occur in up to 62% of patients undergoing SCT, with onset generally within the first month after SCT. In severe cases, 100-day mortality is in excess of 80%. Current management consists of best supportive care, with no agents to date approved for treatment in the USA or the EU. Defibrotide, a polydisperse oligonucleotide, has been shown in phase II and III trials to improve complete response and survival in patients undergoing SCT with severe VOD. This article reviews our current understanding of VOD, and examines recent clinical findings on defibrotide for the treatment and prophylaxis of VOD.

Summary To define a prognostic model for predicting outcome of reduced-intensity allogeneic stem cell transplantation (RIC-ASCT) for myelofibrosis we evaluated 150 homogenously treated patients and developed a new risk score for overall survival (OS). In a multivariate Cox model for OS, only JAK2 V617F wild-type, age ‡57 years and constitutional symptoms were independently predictive for OS (Hazard Ratio: 2AE02; 2AE43 and 2AE80 respectively). Depending on the presence of one, two or all of these factors, HR of death was 3AE08; 4AE70 and 16AE61 respectively (P

Purpose Limited data are available on immunologic responses to primary pandemic H1N1 (2009) vaccination in recipients of allogeneic hematopoietic stem cell transplantation (HSCT) recipients. In 2009 serologic responses to either pandemic H1N1 (2009) vaccine (n = 36) or pandemic H1N1 (2009) infection (n = 2) were studied in 38 HSCT recipients. Methods Responses were measured with a standard hemagglutination-inhibition assay. Fourteen patients had active chronic graft-versus-host disease (cGvHD) at the time of vaccination/infection and seven patients had cGvHD in remission; 11 patients had no immunosuppressive therapy, and 27 patients were on immunosuppressive therapy. Nineteen patients (53%) responded to pandemic H1N1 (2009) vaccination. Two patients had pandemic H1N1 (2009) infection without prior vaccination, and one patient had severe pandemic H1N1 (2009) infection with acute respiratory distress syndrome despite prior single vaccination. Results Non-responders to pandemic H1N1 (2009) vaccination more often had cGvHD (65 vs. 53%) and received second- or third-line therapy (53 vs. 11%), while responders mostly had first-line therapy for cGvHD. While vaccine responders had no or single agent immunosuppressive therapy, non-responders frequently received moderate or intense immunosuppressive therapy. All vaccine recipients previously treated with rituximab were non-responders. Conclusions In summary, the overall response to pandemic H1N1 (2009) vaccination in HSCT recipients was modest. Patients receiving combined immunosuppressive therapy for steroid-refractory cGvHD barely responded to pandemic H1N1 (2009) vaccination.

To the editor: Distinct polymorphisms of NOD2/CARD15 (rs2066844 [SNP08], rs2066845 [SNP12], and rs2066847 [SNP13]) have influence on the incidence of Crohn disease (CD), a chronic inflammatory disorder of the gastrointestinal tract. Similar symptoms of CD and GVHD after allogeneic stem cell

With improved outcome of allogeneic stem cell transplantation (allo-SCT) for hematologic malignancies, long-term complications gain greater importance. Skeletal complications such as osteoporosis or avascular necrosis (AVN) occur frequently in allogeneic recipients with a cumulative incidence of diminished bone mineral density of 24-50% between 2 and 12 months after allo-SCT and a cumulative incidence of AVN in as many as 19% of patients 3 years after allo-SCT. Here, we present a review as part of the German, Austrian, and Swiss Consensus Conference on clinical practice in chronic graft-versus-host disease, held 2009 in Regensburg. The Consensus Conference aimed to achieve a consensus on the current evidence of diagnosis, prevention, and therapeutic options of late complications after allo-SCT summarizing and discussing the literature on these topics. In this report, we provide recommendations for metabolic bone diseases agreed upon by the working party. This includes guidelines for diagnosis, prevention, and therapeutic options in patients with low bone mass or AVN.

Background Allogeneic hematopoietic cell transplantation is considered the preferred post-remission therapy in patients with acute myeloid leukemia cytogenetically defined as being at high risk. To substantiate evidence for allogeneic hematopoietic cell transplantation in first complete remission in these high-risk patients we performed a landmark analysis within a single prospective multicenter treatment trial.By the time of analysis, 2,347 patients had been accrued into the AMLCG 99 trial between 1999 - 2007. Out of this population, 243 patients under 60 years old fulfilled the criteria for high-risk cytogenetics. Landmark analyses were performed with a control cohort, who remained in first complete remission at least the median time from complete remission to transplantation in the intervention group.After standardized induction therapy, 111 patients under 60 years old achieved complete remission. A matched allogeneic donor was identified for 59 patients (30 sibling donors, 29 unrelated donors). Fifty-five patients received an allogeneic hematopoietic cell transplant after a median time of 88 days in first complete remission. Of the remaining 56 patients, 21 relapsed within 90 days after achieving first complete remission and for 7 patients with relevant comorbidities no donors search was initiated, leaving 28 patients given conventional post-remission therapy as the control cohort. The median follow-up of surviving patients was 60.4 months. Patients with an allogeneic donor had substantially better 5-year overall and relapse-free survival rates than the control group (48% versus 18%, P=0.004 and 39% versus 10%, P0.001, respectively). A survival benefit from transplantation was evident regardless of donor type, age and monosomal karyotype. Conclusions Beyond evidence available for subgroups of high-risk patients, the findings of this study establish in a broader manner that allogeneic hematopoietic cell transplantation is a preferable consolidation treatment for patients with acute myeloid leukemia and high-risk cytogenetics. The study was registered at Clinicaltrials.gov as NCT00266136.

We present the case of a 49-year-old male patient with Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disorder (PTLD) limited to the brain that occurred 6 months after allogeneic hematopoietic stem cell transplantation (HSCT). Clinical symptoms included mental confusion, ataxia, and diplopia. Magnetic resonance imaging (MRI) revealed cerebellar and periventricular lesions consistent with an inflammatory process. Cerebrospinal fluid (CSF) analysis, but not peripheral blood, was positive for EBV-DNA, but no malignant cells were found. Brain biopsy was not feasible because of low platelet counts. As we considered a diagnosis of either EBV-associated encephalitis or PTLD, the patient was treated with rituximab combined with antiviral therapy. However, the cerebral lesions progressed and follow-up CSF testing revealed immunoglobulin H clonality as evidence of a malignant process. Subsequent treatment attempts included 2 donor lymphocyte infusions (DLI). Despite treatment, the patient died from autopsy-proven PTLD within 8 weeks of the onset of symptoms. This case demonstrates the clinical and diagnostic challenges of primary cerebral PTLD in a patient following allogeneic HSCT.

Trotz neuartiger Transplantationstechniken im Bereich der allogenen Stammzelltransplantation (SCT) wie optimierte Konditionierungsregime ist die Graft-versus-Host-Disease (GvHD) mit einer signifikanten Morbiditat und Mortalitat assoziiert. Wahrend die Inzidenz der akuten GvHD in den letzten Jahren weitgehend unverandert blieb, nahm die Inzidenz der chronischen GvHD in den letzten 10 Jahren zu. Die traditionelle Einteilung der GvHD nach dem Zeitpunkt der klinischen Manifestation gilt heute als uberholt. Akute GvHD-Bilder treten auch nach 100 Tagen auf, umgekehrt werden primar chronische Bilder auch schon ab dem 2. Monat nach SCT beobachtet. Die aktuell gultige Klassifikation des National Institutes of Health umfasst die klassische akute GvHD bis Tag 100, eine „late-onset“ akute GvHD (nach 100 Tagen) sowie ein Overlap-Syndrom mit Charakteristika einer akuten und chronischen GvHD sowie die klassische chronische GvHD ohne Zeitlimit. Nach wie vor bereitet die Diagnose einer GvHD der Haut haufig differenzialdiagnostische Schwierigkeiten, da Arzneimittelreaktionen und Virusexantheme klinische und histologische Ahnlichkeiten aufweisen konnen. Im folgenden Weiterbildungsbeitrag sollen in einem ersten Teil zunachst die pathophysiologischen Mechanismen, die Stadieneinteilung, die unterschiedlichen Hautmanifestationen der akuten und chronischen GvHD sowie das histopathologische Bild besprochen werden. In einem zweiten Teil werden die Prognose sowie die Prophylaxe und Therapie der GvHD anhand der aktuellen Literatur diskutiert.

Based on expert opinion and retrospective data the National Institutes of Health (NIH) Consensus Development Project proposed criteria for diagnosis and staging of both overall severity as well as organ severity of chronic graft-versus-host disease (cGVHD) for use in clinical trials. In 2008, representatives of German and Austrian allogeneic hematopoietic stem cell transplant (HSCT) centers established a study group on cGVHD during the annual meeting of the German Working Group on Bone Marrow and Blood Stem Cell Transplantation (DAG-KBT) to intensify a dialog among HSCT physicians, pathologists, and medical consultants focusing on the usefulness of the NIH consensus criteria for patient care in clinical practice and to promote collaborations between HSCT centers as well as different medical specialities involved in HSCT. We first conducted a survey of current practices of diagnosis, staging, and overall grading of cGVHD in daily clinical routine by sending an electronic questionnaire to the heads of the HSCT centers. During 3 meetings in 2009, more representatives of allogeneic HSCT centers were included into the discussion process, resulting in 81% participation representing 88% of all allogeneic HSCT activities in Germany, Austria, and Switzerland. During the third consensus meeting held in Regensburg, Germany, from November 6 to November 7, 2009, important agreements were achieved among participant having a strong impact on care of patients with cGVHD. Areas of disagreement such as distinction between classical NIH cGVHD and overlap syndrome or assignment of liver GVHD after day 100 to acute or chronic category will be further assessed in prospective observational studies among participants in the near future.

GvHD remains associated with significant morbidity and mortality despite new techniques for allogeneic stem cell transplantation (SCT), such as optimized conditioning regimens. Within the past ten years, the incidence of acute GvHD has remained unchanged and the incidence of chronic GvHD has even increased. The traditional classification of GvHD according to the time of clinical manifestation is now out-dated. Acute GvHD symptoms may even occur after 100 days; vice versa, primary chronic GvHD may already be observed one month after stem cell transplantation. The current classification introduced by the National Institutes of Health includes classic acute GvHD (up to 100 days), late-onset acute GvHD (after 100 days), as well as an overlap syndrome showing features of acute and chronic GvHD and classic chronic GvHD without any time limit. Diagnosis of GvHD of the skin remains difficult because of histological similarities to drug eruptions and viral exanthems. In this first part of the article the pathophysiology, classification, skin manifestations of acute and chronic GvHD and the histopathology will be presented. In a second part the prognosis, prophylaxis and therapy of GvHD will be discussed.

Steroid refractory chronic graft-versus-host disease (cGVHD) is associated with a significant morbidity and mortality. Although first-line treatment of cGVHD is based on controlled trials, second-line treatment is almost solely based on phase II trials or retrospective analyses. The consensus conference on clinical practice in cGVHD held in Regensburg aimed to achieve a consensus on the current evidence of treatment options as well as to provide guidelines for daily clinical practice. Treatment modalities are the use of steroids and calcineurin inhibitors as well as immunomodulating modalities (photopheresis, mTOR-inhibitors, thalidomide, hydroxychloroquine, vitamin A analogs, clofazimine), and cytostatic agents (mycophenolate mofetil, methotrexate, cyclophosphamide, pentostatin). Recent reports showed some efficacy of rituximab, alemtuzumab, and etanercept in selected patients. Moreover, tyrosine kinase inihibitors such as imatinib came into the field because of their ability to interfere with the platelet-derived growth factor (PDGF-R) pathway involved in fibrosis. An other treatment option is low-dose thoracoabdominal irradiation. Although different treatment options are available, the “trial-and-error system” remains the only way to identify the drug effective in the individual patient, and valid biomarkers are eagerly needed to identify the likelihood of response to a drug in advance. Moreover, the sparse evidence for most treatment entities indicates the urgent need for systematic evaluation of second-line treatment options in cGVHD.

Introduction: Sickle cell disease (SCD) is one of the most prevalent monogenic hematological disorders leading to progressive multi-organ damage and reduced life expectancy despite a significant improvement of conventional and supportive care. Allogeneic hematopoietic stem cell transplantation (HSCT) with a matched sibling donor (MSD) represents currently the only curative treatment option, limited by a donor availability Neurotoxicity (NT) contributes significantly to HSCT-associated morbidity and mortality. Calcineurin inhibitor (CNI) related NT after HSCT is mostly caused by cyclosporine A (CsA) and tacrolimus (FK506) with an overall frequency between 4.2% - 28.8%, and severe NT in 4% - 11%, such as posterior reversible encephalopathy syndrome (PRES), seizures, visual disturbance, cortical blindness, aphasia or ataxia. Particularly in hemoglobinopathies (thalassemia, SCD) the reported incidence is around 30%, possibly also due to impaired hepatic metabolization of CsA and FK506 based on iron overload. However, also infusion modalities might impact on NT, since it was more frequently reported after 4-hours bolus injections (10.3%) than continuous infusion (3.3%). However, the excessive NT observed in SCD might be also related to the systemic vasculopathy, increasing with age and pro-inflammatory triggers after allo-HSCT. Methods: A total of 30 pts aged 3 to 31 years with homozygous SCD or HbS 0/+ ß-Thal were treated between 2012 and 2018. Nine pts received a MSD bone marrow (BM) graft, 21 pts received T-haplo-HSCT from a relative (1 second T-haplo-HSCT due to graft rejection) with a α/β CD19 or CD3/CD19 depleted graft. Post-HSCT immunosuppression consisted of either CsA in 6 MSD and 16 T-haplo-HSCT pts or FK506 in 3 MSD and 6 T-haplo-HSCT pts, both mostly in combination with mycophenolate mofetil (MMF). FK506 was administered as a 20-hours continuous infusion, while CsA was given as 4-hours bolus injections. Dosage was adjusted according to usual target levels (CsA: 120ng/ml; FK506: 7ng/ml). Duration of immunosuppression was >6 months in T-haplo-SCT and Results: Overall CNI-related NT was observed in 32.3% of our HSCT pts. Severe NT such as PRES and visual disturbance combined with aphasia was present in 16.1% (Table 1). Overall, NT was more prevalent in MSD (n=5, 55.5%) than in T-haplo-HSCT pts (n=5, 22.7%). The majority of NT events was observed under CsA prophylaxis (8/10; 80%) and in only 22% (2/9) pts with FK506. All 5 cases of severe NT, particularly all PRES, occurred on CsA. Complete recovery of neurologic symptoms was achieved in all pts spontaneously or after switching CsA to FK506 or everolimus (Table 1). Moreover, 60% of pts with NT was >18 years, and 90% >12 years suggesting an increasing risk with age while a third of patients with pre-existing NT experienced no post-HSCT NT. Of note, 4 of 5 pts with severe NT also experienced a mild acute GvHD (Table 1). The overall (OS) and disease-free survival (DFS) with a median follow-up of 17 months in T-haplo-HSCT pts and 22 months in 9 MSD HSCT pts was 90% vs. 100%, respectively. Conclusions: Our data confirm an elevated risk for NT in SCD pts following allo-HSCT. Importantly, the incidence of NT events seems to be related to age (90% of pts with NT were >12years), donor source (MSD vs. T-Haplo; 55.5% vs 22.7%) and CsA rather than FK506 (CSA 80% vs. FK506 20%). All severe NT (particularly all PRES) were observed in pts with CsA prophylaxis, while the continuous infusion of FK506 might have levelled concentration peaks. Nevertheless, the NT observed with CsA post-HSCT could be the consequence of predominantly CsA-related vascular complications inflicting systemically pre-damaged vessels of SCD pts. The mechanism of action could be similar to other systemic endotheliopathies such as sinusoidal obstruction syndrome (VOD/SOS), transplant-associated microangiopathy (TAM) and acute GvHD which was observed in 4/5 pts with severe NT, compared to an overall GvHD rate of 29%. Disclosures Corbacioglu: Gentium: Consultancy, Honoraria; Jazz Pharmaceuticals: Consultancy, Honoraria.

Introduction: Increasing evidence suggests that the intestinal microbiota is involved in the development of acute graft-vs.-host disease (GVHD) after allogeneic hematopoietic cell transplantation (allo-HCT). We previously reported in single center studies that Enterococcus a) is associated with GVHD (Holler et al., BBMT 2014) and b) can dominate the post-transplant gut microbiota in up to 50% of allo-HCT patients resulting in a 9-fold increased risk of bacteremia (Taur et al, CID 2012). To further investigate the hypothesis that Enterococcus can trigger the development of GVHD, we studied both allo-HCT patients and pre-clinical mouse transplant models. Methods and Results: Stool samples from 1240 allo-HCT patients at 4 different transplant centers in the U.S., Germany and Japan were collected approximately weekly during inpatient hospitalization. The V4-V5 region of the bacterial 16S rRNA genes from 6718 samples was sequenced at one central site on the Illumina platform. We observed Enterococcus mono-domination (relative abundance > 30%) in post-transplant samples ranging from 20 to 60% of patients at different centers (Fig. A, left). This mono-domination was primarily attributable to E. faecium, and was associated with a significantly increased risk for grade 2-4 acute GVHD (Fig. A, right). In three different mouse models we found a transient bloom of E. faecalis around 7 days after transplant in allo-HCT recipients with GVHD (Fig. B; C57BL/6 -> 129SV model). This bloom did not occur in allo-HCT recipients of a T cell depleted allograft without GVHD. To further investigate this Enterococcus bloom, we treated mice with an experimental E. faecalis-strain on days 4 to 6 after transplant and found significantly increased lethal GVHD. Colonizing germ-free mice with a minimal gut flora also lead to increased lethal GVHD when enterococci were added to the gnotobiotic flora (Fig. C). The allo-HCT recipients with Enterococcus-containing flora had also increased serum IFNg levels. Short chain fatty acids (SCFA) can be protective against GVHD and gut inflammation through maintenance of epithelial homeostasis and increases in anti-inflammatory regulatory T cells in the gut. In BMT mouse models, we found that Enterococcus-dominated allo-HCT recipients with GVHD have significantly less cecal butyrate, a major SCFA. Similarly, Enterococcus domination after allo-HCT also leads to a decrease in fecal SCFAs in patients (Fig. D). Next, we hypothesized that intestinal IgA might have a protective role against this pathogen in mice. 16S sequencing of flow sorted IgA-coated vs. non-coated bacteria from fecal samples of allo-HCT patients and transplanted mice revealed no specific IgA-coating pattern of enterococci both before or after transplant rather excluding the hypothesis that IgA might have a protective role against Enterococci. E. faecalis and E. faecium use the disaccharide lactose as a major carbohydrate source for growth and expansion as observed by analyses of the Enterococcus genome and in vitro growth experiments. In mice, we observed that a lactose-free diet significantly decreases the Enterococcus bloom after transplant in allo-T cell recipients and in first survival experiments attenuates lethal GVHD (Fig. E). Conclusion: Our studies in mouse and man demonstrate that the abundance of Enterococcus in the intestinal flora plays a role in the development of GVHD and the prevention of Enterococcus growth with a lactose-free diet can ameliorate GVHD. Disclosures Peled: Seres Therapeutics: Research Funding.

Introduction Despite substantial progress in the treatment of newly diagnosed AML, 20% to 40% of patients do not achieve remission with conventional induction chemotherapy. In addition, 50% to 70% of patients with CR1 are expected to relapse within 3 years. Currently, allogeneic HSCT is thought to be the most reliable curative option for patients with relapsed and/or refractory (r/r) disease. Compared to HSCT in CR1 allogeneic HSCT beyond CR1 is associated with lower survival rates. So far, different predictive factors influencing survival in r/r AML have been identified. However, pretransplantation variables delineating prognostic subgroups after allogeneic HSCT beyond CR1 are less well known and the total number of patients in trials addressing this issue has been limited. Methods We analyzed the outcome after allogeneic HSCT in non-APL-AML patients transplanted with either subsequent 2nd complete remission (CR2), r/r AML or with persisting cytopenia (PC, including patients with hematologic complete remission with incomplete hematologic recovery and patients with persisting bone marrow hypoplasia) after induction or salvage therapy. Of 3989 patients who enrolled into a multicenter clinical trial (AMLCG1999; NCT00266136) of the German Acute Myeloid leukemia Cooperative Group (AMLCG) we identified 498 subjects aged 17 to 74 years who underwent allogeneic HSCT beyond first CR. Before transplantation, all patients received first line treatment either with 6-Thioguanine, cyararabine, daunorubicin (TAD) and high-dose cytarabine, mitoxantrone (HAM) or HAM/HAM. After induction failure (n=97) or relapse (n=401) patients either received salvage chemotherapy (n=299) or directly underwent allogeneic HSCT (n=199). Overall survival (OS) and relapse free survival (RFS) after allogeneic HSCT were the main endpoints for this analysis. Kaplan-Meier analysis was performed to estimate survival probabilities in subgroups. Log-rank tests were used to compare survival groups. Relative hazard rates and differences in subgroups were calculated using cox regression analysis. Results At a median follow-up of 6.5 years for surviving patients, OS and RFS rates were 32% (95% CI 28-36%) and 30% (95% CI 26-34%), respectively. Subgroup analysis revealed an OS of 49% in 128 patients with allogeneic HSCT in CR2. In comparison, 73 patients who underwent allogeneic HSCT with PC after induction (n = 42) / salvage treatment (n = 31) and 297 patients with refractory disease (RD) exhibited an OS of 39% and 23%, respectively (Figure 1). The corresponding cumulative incidences (CI) at 1/6.5 years for death in remission after allogeneic HSCT were 25%/31% for patients transplanted in CR2, 29%/41% for patients transplanted with PC and 30%/46% for patients transplanted with RD, respectively. The cumulative incidence of relapse (CIR) after 6.5 years was 58% for patients transplanted with RD compared to 34% for patients transplanted in CR2 and 31% for patients with PC. Main prognostic factors for survival outcome were remission status prior to allogeneic HSCT and cytogenetic risk category at diagnosis. By contrast, patient age, donor, graft source, remission status after induction therapy and CMV status had no significant impact on survival outcome. Conclusions Long-term OS rates after allogeneic HSCT for patients with r/r AML are considered to range between 20 and 40%. Our analysis indicates that a substantial fraction of patients who received similar first line treatment within one prospective trial is able to achieve long term survival when transplanted beyond CR1. In addition, remission upon salvage therapy prior to allogeneic HSCT might be a relevant prognostic factor for patients with r/r AML. However, whether remission induction prior to HSCT can provide an overall survival benefit in patients with r/r disease is still elusive and is currently being evaluated in a prospective randomized clinical trial (ETAL3-ASAP; NCT02461537). Disclosures Beelen: Medac: Consultancy, Other: Travel Support. Scheid:Novartis: Honoraria, Research Funding; Janssen: Honoraria; Celgene: Honoraria; Takeda: Honoraria, Research Funding; BMS: Honoraria; Amgen: Honoraria. Lenz:Celgene Corp.: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding, Speakers Bureau; Novartis: Research Funding; Roche: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding; Bayer: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Other: Travel, Accomodations, Expenses, Research Funding, Speakers Bureau; Gilead: Consultancy, Honoraria. Hiddemann:Bayer: Consultancy, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; F. Hoffman-La Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Stelljes:MSD: Consultancy; JAZZ: Honoraria; Amgen: Honoraria; Novartis: Honoraria; Pfizer: Consultancy, Honoraria, Research Funding.

Introduction. Recurrent disease is the major cause of treatment failure after allogeneic stem cell transplantation (SCT) in patients with AML. Second SCT (SCT2) is a valid treatment option in this setting but outcome is relatively poor. Haplo-identical (haplo) SCT is increasingly used over the last decade due to the introduction of non T-depleted methods. Prior studies have shown similar outcome when using the same or different HLA-matched donor for SCT2. However, there is relatively limited data on the use of haplo-donors. Methods and Results. The study included 556 patients with AML relapsing after a first allogeneic SCT (SCT1) given in CR1 from an HLA-matched sibling (sib, n= 294) or a matched unrelated donor (MUD, n=262) and given SCT2 during the years 2006-2016. The median age at SCT2 was 46 years (20-73). 247 patients were in CR2 (44%) and 309 had active leukemia (55%) at the time of SCT2. The conditioning regimen was myeloablative (MAC, 66%) or reduced-intensity (RIC, 34%) for SCT1, and 41% and 59%, respectively for SCT2. 19% of all patients had acute GVHD grade II-IV and 20% had chronic GVHD after SCT1 and before relapse. Patients were divided into 3 groups based on the donor selected for SCT2; 1) same donor (n=163, sib/sib-112, MUD/MUD-51), 2) different HLA-matched donor (n=305, sib/different sib-44, sib/MUD-93, MUD/ different MUD- 168), 3) haplo-donor (n=88, sib/haplo-45, MUD/haplo-43). All haploSCT were non T-depleted. There were some differences between the 3 groups in the timing of relapse and SCT2. The median time from SCT1 to relapse was similar; 10.6, 12.5 and 9.3 months, respectively (P=0.14). However, the median time from relapse to SCT2 was shorter for the same donor group; 2.8, 3.7 and 3.5 months, respectively (P Conclusions. Second SCT with the same donor or different matched donor is associated with similar outcomes in patients with relapsed AML after a first SCT. However, SCT2 with a haplo-donor is associated with higher NRM and lower LFS, mostly in patients given MAC in SCT1. Prior chronic GVHD after SCT1 is associated with lower relapse rate after SCT2. The role of prior chronic GVHD in donor selection should be further investigated. Disclosures Finke: Medac: Consultancy, Honoraria, Other: travel grants, Research Funding; Neovii: Consultancy, Honoraria, Other: travel grants, Research Funding; Novartis: Consultancy, Honoraria, Other: travel grants, Research Funding; Riemser: Consultancy, Honoraria, Research Funding. Gramatzki:Affimed: Research Funding. Stelljes:Novartis: Honoraria; Amgen: Honoraria; JAZZ: Honoraria; MSD: Consultancy; Pfizer: Consultancy, Honoraria, Research Funding. Stoelzel:Neovii: Speakers Bureau. Mohty:MaaT Pharma: Consultancy, Honoraria.

Intestinal microbiota composition is associated with important outcomes after allo-HCT including survival, relapse, GVHD, and infections. These observations have been made almost exclusively by characterizing the microbiota in the first weeks after transplantation, and in single-center studies. We previously reported that intestinal diversity measured peri-neutrophil engraftment is predictive of overall survival in a multicenter cohort. Here, we hypothesized that pre-HCT microbiota configuration may also be an important determinant of post-transplantation outcomes. We report a multicenter analysis conducted at 4 independent international institutions to test this hypothesis. We collected 1922 stool samples ~weekly from 991 unique allo-HCT patients at four international transplant centers: Cohorts 1 and 2 in the US, cohort 3 in Europe, and cohort 4 in Japan. The patients-all adult recipients of allo-HCT-varied in underlying diagnosis, donor-graft sources, conditioning intensity, and GVHD prophylaxis. Samples from all 4 centers were sequenced and analyzed at a central laboratory using the V4-V5 region of 16S rRNA. For patients with multiple samples within the pre-HCT sampling period, which we defined as day -20 to 0, median values were used. On average, patients from all 4 transplantation centers had reduced microbiota diversity pre-HCT, as measured by median α-diversity (inverse Simpson) values that were 1.7-to-2.5-fold lower than those of healthy volunteers. This comparison was made both in volunteers whose samples we sequenced ourselves and in a publicly available dataset (Fig A, p We next asked how similar these pre-HCT communities are across geography. We found that Bray-Curtis distances between institutions were reproducibly much smaller in magnitude than the changes observed over time during transplantation (Fig C, p In order to characterize these clinically relevant low-diversity phenotypes, we defined domination as a microbiota injury in which any operational taxonomic unit comprises >30% of bacterial abundance. The dominating taxa belonged to multiple genera, the most common being Enterococcus, Streptococcus, Lactobacillus, Escherichia, and Klebsiella (Fig E) as annotated by Greengenes and NCBI databases. At all four institutions, the cumulative incidence of intestinal domination by any organism was >50% by day 0 and was >87% by day +28 (Fig F). We performed additional analyses in the largest cohort and found that the low-diversity state is associated with exposure to broad-spectrum antibiotics, conditioning intensity, and low calorie intake. We demonstrate that HCT patients at 4 institutions on 3 continents presented with microbiota configurations that were similar to one another and distinct from those of healthy individuals. Severe microbiota injury as revealed by domination is a common event whose development begins before allograft infusion, and pre-HCT microbiota injury predicts poor overall survival. These observations suggest the pre-HCT period as a window of opportunity to (a) assess microbiota injury as part of comorbidity evaluation, (b) inform selection of antibiotic prophylaxis, gut-decontamination, GVHD-prophylaxis, or conditioning regimens, and (c) intervene with microbiota injury-remediation or prevention strategies. Figure. Figure. Disclosures Peled: Seres Therapeutics: Research Funding. Perales:Merck: Other: Personal fees; Takeda: Other: Personal fees; Abbvie: Other: Personal fees; Novartis: Other: Personal fees; Incyte: Membership on an entity's Board of Directors or advisory committees, Other: Personal fees and Clinical trial support. Jenq:MicrobiomeDx: Consultancy; Ziopharm Oncology: Consultancy; Seres Therapeutics, Inc.: Membership on an entity's Board of Directors or advisory committees; Seres Therapeutics, Inc.: Patents & Royalties.

Background: Sickle cell disease (SCD) is an inherited disorder with an estimate of 300,000 affected newborns per year worldwide. Despite improvements in preventive measures and conventional therapy, substantial morbidity and mortality, resulting in a reduced life expectancy persist. Allogeneic hematopoietic stem cell transplantation (HSCT) with a matched sibling donor (MSD) is currently the curative standard of care. However, matched donor availability is Methods: We report the results of 29 pts with advanced stage SCD transplanted with either a T-cell depleted haploidentical regimen (20 pts, median age 13 years, range 3-31 years) or with bone marrow from a matched family donor (MSD, 9 pts, median age 14, range 9-25 years). Indication for HSCT was advanced stage SCD related complications. Pts with a MSD received a bone marrow (BM) graft. Pts requiring an alternative donor were transplanted with an αß/CD19 (n=5) or CD3/CD19 (n=15) depleted graft from a haploidentical family donor. The conditioning regimen for both groups was identical except that antithymoglobulin (ATG-Neovii®) was given upfront on day -10 to -8 in T-haplo-HSCT and on day -3 to -1 in MSD. Chemotherapy consisted of thiotepa 2 x 5 mg/kg, fludarabine 4 x 40 mg/m2 and treosulfan 3 x 14 g/m2, given between days -10 and -2. Post-HSCT immunosuppression consisted of mofetil mycophenolate and tacrolimus or cyclosporine A for a duration >6 months in T-haplo-HSCT and Results: The conditioning regimen was well tolerated in all pts with no high-grade transplant related toxicity. The overall (OS) and disease-free survival (DFS) with a median follow-up of 17 months in 20 advanced stage mostly adolescent and adult T-haplo-HSCT pts and 22 months in 9 MSD HSCT pts was 90% vs. 100%, respectively. Engraftment was achieved in most pts with stable chimerism over 90%, except for 4 pts with a stable MC in the T-haplo SCT group and 1 patient in the MSD group off immunosuppression. All pts presented a complete BM engraftment of red cell precursors. Only one patient in the T-haplo-HSCT group with a mixed chimerism is still under immunosuppression. The post-HSCT bacterial infectious complications were comparable in both groups and the most common observed viral infections were systemic cytomegaly virus (CMV), adenovirus (ADV), polyomavirus (BKV) and Epstein Barr virus (EBV) reactivations which were successfully treated with intravenous antiviral drugs or virus specific T-cells. Two patients in the T-haplo-HSCT group achieved a DFS off immunosuppression but succumbed to post-HSCT complications. One developed a rotavirus gastroenteritis and an uncontrolled CMV pneumonitis. The other a late graft failure and succumbed to a macrophage activation syndrome. None of our pts developed a Glucksberg Grade III-IV acute GvHD and in the T-haplo SCT group 4 pts (20%) and in the MSD group 2 pts (22%) developed a steroid sensitive mild to moderate cGvHD (fasciitis/oral as well as mild cutaneous GvHD). No extensive cGvHD was observed. To our knowledge this is the largest group of advanced stage SCD pts transplanted with either a T-haplo-HSCT or a MSD approach, according to donor availability, with an almost identical regimen in a direct comparative design. These preliminary results demonstrate increasing evidence for the feasibility, safety and efficacy of a T-haplo-HSCT using CD3/CD19 or αβ/CD19 depleted grafts, in order to offer a curative option to the majority of pts with SCD. A prospective, stratified non-inferiority trial is in preparation (EudraCT number 2018-002652-33) in order to confirm these preliminary results in a large prospective cohort. Disclosures Corbacioglu: Gentium: Consultancy, Honoraria; Jazz Pharmaceuticals: Consultancy, Honoraria.

Invasive fungal infections (IFI) are major causes of death in high-risk haematological patients receiving induction therapy for acute leukaemia or intensified immunosuppression due to acute or chronic graft-vs.-host disease (GvHD) following allogeneic stem cell transplantation (SCT). Recently, two randomised studies showed the efficacy of a posaconazole prophylaxis (PP) in these patients to prevent IFI. This prompted the strong recommendation for the use of PP in national and international guidelines. As we started PP in our leukaemia and transplantation unit in summer 2007, we retrospectively analysed the impact of PP on the incidence of possible, probable or proven IFI in this group of patients. Incidence of IFI according to the revised EORTC criteria, published in 2008, was reviewed retrospectively in a group of high-risk patients treated in our unit 1 year before the start of PP compared with the same group in the following year with PP. First analysis was performed on an intention-to-treat basis comparing patients during 1 year of PP with the same group of patients in the year before the start of PP. In a second, deeper analysis, patients were grouped for fluconazole or posaconazole irrespective of the time period the prophylaxis was given. In a first intent-to-treat analysis, 56 patients were analysed in the period without PP (noPP) compared with 34 patients in the period with PP. Overall IFI rates (possible, probable and proven IFI) were reduced from 47% (noPP group) to 35% (PP group). In a second analysis, only patients receiving either fluconazole or PP were analysed, resulting in 29 patients in the noPP group and 36 patients in the PP group. There was a reduction in overall IFI in the PP group especially in the acute myeloid leukaemia (AML) induction patients, but this does not reach statistical significance because of low patient numbers. However, initiation of antifungal therapy was significantly less frequent in AML induction patients in the PP group compared with the noPP group. Unfortunately, this does not result in reduced mortality rates, as mortality in the PP group is higher (15% vs. 7%) than in noPP patients because of double the number of patients with severe GvHD in the PP group. Both breakthrough infections were documented in this subgroup of patients. Our data, collected in every day clinical practice, add further evidence to the advantage of a PP strategy in this group of high-risk patients. However, more data are urgently needed to assess the impact of PP on the incidence and pattern of fungal infections and the strategies to be used in patients with persisting fever and pulmonary infiltrates receiving PP, especially in the setting of SCT and GvHD.