Search results for "Stem Cell"
showing 10 items of 2354 documents
Clinical virology of cytomegalovirus infection following hematopoietic transplantation
2010
Cytomegalovirus (CMV) causes significant morbidity and mortality in allogeneic stem cell transplant recipients. The incidence of early CMV disease has been dramatically reduced by use of preemptive therapeutic strategies. Nevertheless, a trend toward a later appearance of CMV disease is being increasingly recognized. Currently, quantitative real-time PCR assays are the first-line choice for monitoring active CMV infection. However, no threshold DNAemia levels for triggering the initiation of preemptive therapy have been clinically validated in large studies. Although more time limited than universal prophylaxis, preemptive therapy strategies may also result in over treatment. Combined viro…
P046 Deconstructing HLA-C mismatch in hematopoietic stem cell transplantation
2016
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…
Induced Pluripotent Mesenchymal Stromal Cell Clones Retain Donor-derived Differences in DNA Methylation Profiles
2012
Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) is an epigenetic phenomenon. It has been suggested that iPSC retain some tissue-specific memory whereas little is known about interindividual epigenetic variation. We have reprogrammed mesenchymal stromal cells from human bone marrow (iP-MSC) and compared their DNA methylation profiles with initial MSC and embryonic stem cells (ESCs) using high-density DNA methylation arrays covering more than 450,000 CpG sites. Overall, DNA methylation patterns of iP-MSC and ESC were similar whereas some CpG sites revealed highly significant differences, which were not related to parental MSC. Furthermore, hypermethylation in iP-MSC…
IL-4-mediated drug resistance in colon cancer stem cells
2008
Cancer stem cells are defined as cells able to both extensively self-renew and differentiate into progenitors. Cancer stem cells are thus likely to be responsible for maintaining or spreading a cancer, and may be the most relevant targets for cancer therapy. The CD133 glycoprotein was recently described as a reliable cancer stem-like cell marker in colon carcinoma. CD133+ cells are both necessary and sufficient to initiate tumour growth in animal models. The CD133+ cell population and spheroid cultures contain cells expressing the stem cell marker Musashi-1 which is involved in maintenance of stem cell fate in several tissues and importantly, this expression is maintained in stem-like cells…
The art of forging neurons: direct reprogramming of somatic cells into induced neuronal cells
2013
Abstract Cellular reprogramming has shed new light on the plasticity of terminally differentiated cells and unearthed novel strategies for cell-based therapies to treat neurological disorders. With accumulating knowledge of the programs underlying the genesis of the distinct neural cell types, particularly the identification of crucial transcription factors and microRNAs, reprogramming of somatic cells of different origins into induced neuronal cells or neural stem cells has been successfully achieved. Starting with the general concept of reprogramming, we discuss three different paradigms: (1) direct conversion of central nervous system (CNS) foreign cells such as skin fibroblasts in…
XPO1 (Exportin-1) Is a Major Regulator of Human Erythroid Differentiation. Potential Clinical Applications to Decrease Ineffective Erythropoiesis of …
2015
Abstract Background We and others have shown that normal human erythroid cell maturation requires a transient activation of caspase-3 at late stages of maturation (Zermati et al, J Exp Med 2001). We further documented that, in human erythroblasts, the chaperone HSP70 is constitutively expressed and, at late stages of maturation, translocates into the nucleus and protects GATA-1, the master transcriptional factor critical for erythropoiesis, from caspase-3 cleavage (Ribeil et al, Nature 2007). During the maturation of human β-TM erythroblasts, HSP70 is sequestrated by excess of α-globin chains in the cytoplasm and as a consequence, GATA-1 is no longer protected from caspase-3 cleavage result…
Alteration of HSC Functions in Thalassemia
2015
Abstract Beta-thalassemia represents one of the most globally widespread monogenic disorders and is characterized by significantly reduced or absent synthesis of hemoglobin beta-chains. In its severe form the insufficient production of adult hemoglobin results in altered erythropoiesis, hemolytic anemia, bone marrow (BM) hematopoietic hyperplasia and splenomegaly often associated with extramedullary hematopoiesis, requiring regular blood transfusions and iron chelation treatment. Over the last two decades many progresses were made in the field of allogeneic bone marrow (BM) transplantation to definitively cure beta-thalassemia. In parallel, experimental autologous transplantation protocols …
Host-directed therapies for COVID-19
2021
Purpose of review Severe acute respiratory syndrome coronavirus-2-induced hyperinflammation is a major cause of death or end-organ dysfunction in COVID-19 patients. We review adjunct host-directed therapies (HDTs) for COVID-19 management. Recent findings The use of umbilical cord-derived mesenchymal stem cells as HDT for COVID-19 has been shown to be safe in phase 1 and 2 trials. Trials of anti-interleukin-6 receptor antibodies show promising mortality benefit in hospitalized COVID-19 patients. Repurposed drugs and monoclonal antibodies targeting specific cytokines acting on different aspects of the pro- and anti-inflammatory cascades are under evaluation. Summary A range of HDTs shows prom…
Interferon-α as an Antagonist to Proinflammatory and Hematopoietic Cytokines
1994
TLRs control hematopoiesis during infection
2013
Recent research has shown that (i) Toll-like receptor (TLR) agonists drive hematopoietic stem and progenitor cells (HSPCs) to proliferate and differentiate along the myeloid lineage in vitro, and (ii) direct TLR-mediated stimulation of HSPCs also promotes macrophage differentiation in vivo following infection. These new insights demonstrate that TLR signaling in HSPCs, in addition to other TLR-dependent mechanisms, can contribute to HSPC expansion and myeloid differentiation after infection. Evidence is, therefore, mounting that direct TLR-induced programming of hematopoiesis plays a key role in host defense by rapidly replenishing the innate immune system with the cells needed to deal with…