Hematopoietic stem cells (HSCs) are generated via a natural transdifferentiation process known as endothelial-to-hematopoietic cell transition (EHT). Due to small numbers of embryonal arterial cells undergoing EHT and the paucity of markers to enrich for hemogenic endothelial cells, the genetic program driving HSC emergence is largely unknown. Here, we use a highly sensitive RNAseq method to examine the whole transcriptome of small numbers of enriched aortic HSCs (CD31+cKit+Ly6aGFP+), hemogenic endothelial cells (CD31+cKit-Ly6aGFP+) and endothelial cells (CD31+cKit-Ly6aGFP-). Overall design: Comparison of mRNA profiles of endothelial cells, hemogenic endothelial cells, and hematopoietic stem cells generated by deep-sequencing of sorted populations from pool of embryos, in triplicate.
Whole-transcriptome analysis of endothelial to hematopoietic stem cell transition reveals a requirement for Gpr56 in HSC generation.
No sample metadata fields
View SamplesSequencing libraries were generated from total RNA samples following the mRNAseq protocol for the generation of single end (16-36 hpf, 5 day larvae, adult head and adult tail) or paired end (24 hpf) libraries (Illumina). Single end reads of 36 nucleotides and paired end reads (2 x 76 nucleotides) were obtained with a GAIIx (Illumina). Gene expression at the different stages/tissu was assessed by cufflinks and HTseq. Overall design: RNAseq on 5 differents samples: 24hpf embryos, pool of 16 hour to 36 hour embryos, 5 days old larvea, adult head and adult tail
Genome-wide, whole mount in situ analysis of transcriptional regulators in zebrafish embryos.
No sample metadata fields
View SamplesRegulatory CD4+ T cells (Tregs) are functionally distinct from conventional CD4+ T cells (Tconvs). To understand Treg identity, we have compared by proteomics and transcriptomics human naïve (n) and effector (e)Tregs, Tconvs and transitional FOXP3+ cells. Among these CD4+ T cell subsets, we detected differential expression of 421 proteins and 640 mRNAs, with only 48 molecules shared. Fifty proteins discriminated Tregs from Tconvs. This common Treg protein signature indicates altered signaling by TCR-, TNF receptor-, NFkB-, PI3 kinase/mTOR-, NFAT- and STAT pathways and unique cell biological and metabolic features. Another protein signature uniquely identified eTregs and revealed active cell division, apoptosis sensitivity and suppression of NFkB- and STAT signaling. eTreg fate appears consolidated by FOXP3 outnumbering its partner transcription factors. These features explain why eTregs cannot produce inflammatory cytokines, while transitional FOXP3+ cells can. Our collective data reveal that Tregs protect their identity by a unique “wiring” of signalling pathways Overall design: mRNA profiles of 5 CD4+ T cell populations were generated by deep sequencing, in triplicate
Proteomic Analyses of Human Regulatory T Cells Reveal Adaptations in Signaling Pathways that Protect Cellular Identity.
Subject
View SamplesAlmost a quarter of pediatric patients with Acute Lymphoblastic Leukemia (ALL) suffer from relapses. The biological mechanisms underlying therapy response and development of relapses have remained unclear. In an attempt to better understand this phenomenon, we have analyzed 41 matched diagnosis relapse pairs of ALL patients using genomewide expression arrays (82 arrays) on purified leukemic cells. In roughly half of the patients very few differences between diagnosis and relapse samples were found (stable group), suggesting that mostly extra-leukemic factors (e.g., drug distribution, drug metabolism, compliance) contributed to the relapse. Therefore, we focused our further analysis on 20 samples with clear differences in gene expression (skewed group), reasoning that these would allow us to better study the biological mechanisms underlying relapsed ALL. After finding the differences between diagnosis and relapse pairs in this group, we identified four major gene clusters corresponding to several pathways associated with changes in cell cycle, DNA replication, recombination and repair, as well as B cell developmental genes. We also identified cancer genes commonly associated with colon carcinomas and ubiquitination to be upregulated in relapsed ALL. Thus, about half of relapses are due to selection or emergence of a clone with deregulated expression of a genes involved in pathways that regulate B cell signaling, development, cell cycle, cellular division and replication.
Genome-wide expression analysis of paired diagnosis-relapse samples in ALL indicates involvement of pathways related to DNA replication, cell cycle and DNA repair, independent of immune phenotype.
Sex, Specimen part, Disease
View SamplesBackground and Purpose—Analyzing genes involved in development and rupture of intracranial aneurysms can enhance knowledge about the pathogenesis of aneurysms, and identify new treatment strategies. We compared gene expression between ruptured and unruptured aneurysms and control intracranial arteries. Methods—We determined expression levels with RNA sequencing. Applying a multivariate negative binomial model, we identified genes that were differentially expressed between 44 aneurysms and 16 control arteries, and between 22 ruptured and 21 unruptured aneurysms. The differential expression of 8 relevant and highly significant genes was validated using digital polymerase chain reaction. Pathway analysis was used to identify enriched pathways. We also analyzed genes with an extreme pattern of differential expression: only expressed in 1 condition without any expression in the other. Results—We found 229 differentially expressed genes in aneurysms versus controls and 1489 in ruptured versus unruptured aneurysms. The differential expression of all 8 genes selected for digital polymerase chain reaction validation was confirmed. Extracellular matrix pathways were enriched in aneurysms versus controls, whereas pathways involved in immune response and the lysosome pathway were enriched in ruptured versus unruptured aneurysms. Immunoglobulin genes were expressed in aneurysms, but showed no expression in controls. Conclusions—For rupture of intracranial aneurysms, we identified the lysosome pathway as a new pathway and found further evidence for the role of the immune response. Our results also point toward a role for immunoglobulins in the pathogenesis of aneurysms. Immune-modifying drugs are, therefore, interesting candidate treatment strategies in the prevention of aneurysm development and rupture. Overall design: RNA sequencing of 44 intracranial aneurysm samples (including 21 unruptured, 22 ruptured and 1 undetermined) and 16 control samples of the intracranial cortical artery
RNA Sequencing Analysis of Intracranial Aneurysm Walls Reveals Involvement of Lysosomes and Immunoglobulins in Rupture.
Sex, Age, Subject
View SamplesColon cancer is a major cause of cancer deaths in Western countries and is associated with diets high in red meat. Heme, the iron-porphyrin pigment of red meat, induces cytotoxicity of gut contents which injures surface cells leading to compensatory hyperproliferation of crypt cells. This hyperproliferation results in epithelial hyperplasia which increases the risk of colon cancer. In humans, a high red-meat diet increases Bacteroides spp in feces. Therefore, we simultaneously investigated the effects of dietary heme on colonic microbiota and on the host mucosa of mice. Whole genome microarrays showed that heme injured the colonic surface epithelium and induced hyperproliferation by changing the surface to crypt signaling. Using 16S rRNA phylogenetic microarrays, we investigated whether bacteria play a role in this changed signaling. Heme increased Bacteroidetes and decreased Firmicutes in colonic contents. This shift was most likely caused by a selective susceptibility of Gram-positive bacteria to heme cytotoxic fecal water, which is not observed for Gram-negative bacteria, allowing expansion of the Gram-negative community. The increased amount of Gram-negative bacteria most probably increased LPS exposure to colonocytes, however, there is no appreciable immune response detected in the heme-fed mice. There was no functional change in the sensing of the bacteria by the mucosa, as changes in inflammation pathways and Toll- like receptor signaling were not detected. This unaltered host-microbe cross-talk indicates that the changes in microbiota did not play a causal role in the observed hyperproliferation and hyperplasia.
Dietary heme alters microbiota and mucosa of mouse colon without functional changes in host-microbe cross-talk.
Sex, Age, Specimen part
View SamplesPreviously, we showed that dietary heme injured the colonic surface epithelium and induced hyperproliferation by changing the surface to crypt signaling. In this study we investigated whether bacteria play a role in this changed signaling. Dietary heme increased the Bacteroidetes and decreased the Firmicutes in colonic content. This shift was caused by a selective susceptibility of Gram-positive bacteria to the heme cytotoxic fecal waters, which is not observed for Gram-negative bacteria allowing expansion of the Gram-negative community. The increased amount of Gram-negative bacteria increased LPS exposure to colonocytes, however, there is no appreciable immune response detected in the heme-fed mice. There were no signs of sensing of the bacteria by the mucosa, as changes in TLR signaling were not present. This lack of microbe-host cross talk indicated that the changes in microbiota do not play a causal role in the heme-induced hyperproliferation.
Dietary heme alters microbiota and mucosa of mouse colon without functional changes in host-microbe cross-talk.
Sex, Age, Specimen part, Treatment
View SamplesIn order to understand the molecular mechanism behind Vulvar Intraepithelial Neoplasia (VIN), we have analyzed the gene expression profile of VIN lesions in comparison to controls.
HPV related VIN: highly proliferative and diminished responsiveness to extracellular signals.
Sex
View SamplesOculopharyngeal muscular dystrophy (OPMD) is a late-onset progressive muscle disorder caused by a poly-alanine expansion mutation in PABPN1. The hallmark of OPMD is the accumulation of the mutant protein in insoluble nuclear inclusions. The molecular mechanisms associated with disease onset and progression are unknown. We performed a high-throughput cross-species transcriptome study of affected muscles from two OPMD animal models and from patients at pre-symptomatic and symptomatic stages. The most consistently and significantly OPMD-deregulated pathway across species is the ubiquitin-proteasome system (UPS). By analyzing expression profiles, we found that the majority of OPMD-deregulated genes are age-associated. Based on expression trends, disease onset can be separated from progression; the expression profiles of the proteasome-encoding genes are associated with onset but not with progression. In a muscle cell model, proteasome inhibition and the stimulation of immunoproteasome specifically affect the accumulation and aggregation of mutant PABPN1. We suggest that proteasome down-regulation during muscle aging triggers the accumulation of expPABPN1 that in turn enhances proteasome deregulation and leads to intranuclear inclusions (INI) formation.
Deregulation of the ubiquitin-proteasome system is the predominant molecular pathology in OPMD animal models and patients.
Sex, Age, Disease, Disease stage
View SamplesRationale: Lipopolysaccharide (LPS) is ubiquitous in the environment. Inhalation of LPS has been implicated in the pathogenesis and/or severity of several lung diseases, including pneumonia, chronic obstructive pulmonary disease and asthma. Alveolar macrophages are the main resident leukocytes exposed to inhaled antigens. Objectives: To obtain insight into which innate immune pathways become activated within human alveolar macrophages upon exposure to LPS in vivo.
Gene expression profiles in alveolar macrophages induced by lipopolysaccharide in humans.
Sex, Specimen part, Treatment, Subject
View Samples