Project description:The aim of this study is to assess the Fecal Microbiota Transplantation (FMT) efficacy in the prevention of allogeneic hematopoietic stem cell transplantation (allo-HSCT) complications and particularly Graft versus Host Disease (GvHD).
The hypothesis of this study is that allogeneic FMT may improve outcomes of these patients.
Project description:This is a data collection study that will examine the general diagnostic and treatment data associated with the reduced-intensity chemotherapy-based regimen paired with simple alemtuzumab dosing strata designed to prevented graft failure and to aid in immune reconstitution following hematopoietic stem cell transplantation.
Project description:<p><strong>BACKGROUND:</strong> Hematopoietic stem cell transplantation is a curative procedure for a variety of conditions. Despite major advances, a plethora of adverse clinical outcomes can develop post-transplantation including graft-versus-host disease and infections, which remain the major causes of morbidity and mortality. There is increasing evidence that the gastrointestinal microbiota is associated with clinical outcomes post-hematopoietic stem cell transplantation. Herein, we investigated the longitudinal dynamics of the gut microbiota and metabolome and potential associations to clinical outcomes in pediatric hematopoietic stem cell transplantation at a single centre.</p><p><strong>RESULTS:</strong> On admission (baseline), the majority of patients presented with a different gut microbial composition in comparison to healthy control children with a significantly lower alpha diversity. A further, marked decrease in alpha diversity was observed immediately post-transplantation and in most microbial diversity, and composition did not return to baseline status while hospitalized. Longitudinal trajectories identified continuous fluctuations in microbial composition, with the dominance of a single taxon in a significant proportion of patients. Using pam clustering, three clusters were observed in the dataset. Cluster 1 was common pre-transplantation, characterized by a higher abundance of <em>Clostridium XIVa</em>, <em>Bacteroides</em> and <em>Lachnospiraceae</em>; cluster 2 and cluster 3 were more common post-transplantation with higher abundance of <em>Streptococcus</em> and <em>Staphylococcus</em> in the former whilst <em>Enterococcus</em>, <em>Enterobacteriaceae</em> and <em>Escherichia</em> predominated in the latter. Cluster 3 was also associated with a higher risk of viraemia. Likewise, further multivariate analysis reveals <em>Enterobacteriaceae</em>, viraemia, use of total parenteral nutrition and various antimicrobials contributing towards cluster 3, <em>Streptococcaceae</em>, <em>Staphylococcaceae</em>, <em>Neisseriaceae</em>, vancomycin and metronidazole contributing towards cluster 2. <em>Lachnospiraceae</em>, <em>Ruminococcaceae</em>, <em>Bifidobacteriaceae</em> and not being on total parenteral nutrition contributed to cluster 1. Untargeted metabolomic analyses revealed changes that paralleled fluctuations in microbiota composition; importantly, low fecal butyrate was associated with higher risk of viraemia.</p><p><strong>CONCLUSIONS:</strong> These findings highlight the frequent shifts and dominations in the gut microbiota of pediatric patients undergoing hematopoietic stem cell transplantation. The study reveals associations between the fecal microbiota, metabolome and viraemia. To identify and explore the potential of microbial biomarkers that may predict risk of complications post-HSCT, larger multi-centre studies investigating longitudinal microbial profiling in pediatric hematopoietic stem cell transplantation are warranted.</p>
Project description:Comparing between plasma cytokine proteins on AML patients with or without aGVHD Comparing between plasma cytokine proteins on AML patients with or without aGVHD after allogeneic hematopoietic stem cell transplantation, Day+14
Project description:Long non-coding RNAs (lncRNAs) and miRNAs have emerged as crucial regulators of gene expression and cell fate decisions. Here we present an integrated analysis of the ncRNA-transcriptome of purified human hematopoietic stem cells (HSCs) and their differentiated progenies, including granulocytes, monocytes, T-cells, NK-cells, B-cells, megakaryocytes and erythroid precursors, which we correlated with the ncRNA expression profile of 48 pediatric AML samples to establish a core lncRNA stem cell signature in AML.Linear (PCA) and nonlinear (t-SNE) dimensionality reduction of 46 pediatric AML samples including Down syndrome AMKL, core-binding factor AMLs (inv[16] or t[8;21]) and MLL-rearranged leukemias mapped most samples to a space between HSCs and differentiated cells together with the myeloid progenitors. A subset of AML-samples mapped closely to healthy HSCs, including most of the DS-AMKLs and MLL-AMLs. Following the incorporation of acute myeloid leukemia (AML) samples into the landscape, we further uncover prognostically relevant ncRNA stem cell signatures shared between AML blasts and healthy hematopoietic stem cells.
Project description:Chromatin organization is a highly orchestrated process that influences gene expression, in part by modulating access of regulatory factors to DNA and nucleosomes. We found that the chromatin accessibility regulator HMGN1, a target of recurrent DNA copy gains in leukemia, controls myeloid differentiation. HMGN1 amplification was associated with increased accessibility, expression, and histone H3K27 acetylation of loci important for hematopoietic stem cell (HSC) function and AML, such as HoxA cluster genes. In vivo, HMGN1 overexpression was linked to decreased quiescence and increased HSC activity in bone marrow transplantation. HMGN1 overexpression also cooperated with the AML-ETO9a fusion oncoprotein to impair myeloid differentiation and enhance leukemia stem cell (LSC) activity. Inhibition of histone acetyltransferases CBP/p300 relieved the HMGN1-associated differentiation block. These data nominate factors that modulate chromatin accessibility as regulators of HSCs and LSCs and suggest that targeting HMGN1 or its downstream effects on histone acetylation could be therapeutically active in AML.
Project description:This study will determine the safety and applicability of experimental forms of umbilical cord blood (UCB) transplantation for patients with high risk hematologic malignancies who might benefit from a hematopoietic stem cell transplant (HSCT) but who do not have a standard donor option (no available HLA-matched related donor (MRD), HLA-matched unrelated donor (MUD)), or single UCB unit with adequate cell number and HLA-match).