Because of inherent differences between deceased donor (DD) and living donor (LD) liver grafts, we hypothesize that the molecular signatures will be unique, correlating with specific biologic pathways and clinical patterns. Following reperfusion, 579 genes in DD grafts and 1324 genes in LDs were differentially expressed (p<0.005). Many up-regulated LD genes were related to regeneration, biosynthesis and cell cycle, and a large number of down-regulated genes were linked to hepatic metabolism and energy pathways correlating with post-transplant clinical laboratory findings. There was significant up-regulation of inflammatory/immune genes in both DD and LD, each with a distinct pattern. Gene expression patterns of select genes associated with inflammation and regeneration in LD and DD grafts correlated with protein expression.
Unique early gene expression patterns in human adult-to-adult living donor liver grafts compared to deceased donor grafts.
No sample metadata fields
View SamplesThe role of chronic hepatitis C virus (HCV) in the pathogenesis of HCV-associated hepatocellular carcinoma (HCC) is not completely understood, particularly at the molecular level.
Genes involved in viral carcinogenesis and tumor initiation in hepatitis C virus-induced hepatocellular carcinoma.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The histone methyltransferase SETDB1 represses endogenous and exogenous retroviruses in B lymphocytes.
Specimen part
View SamplesGenome stability relies on epigenetic mechanisms that enforce repression of endogenous retroviruses (ERVs). Current evidence suggests that distinct chromatin-based mechanisms repress ERVs in cells of embryonic origin (histone methylation-dominant) versus more differentiated cells (DNA methylation-dominant). However, the latter aspect of this model has not been tested. Remarkably, and in contrast to the prevailing model, we find that repressive histone methylation catalyzed by the enzyme SETDB1 is critical for suppression of specific ERV families and exogenous retroviruses in committed B-lineage cells from adult mice. The profile of ERV activation in SETDB1-deficient B cells is distinct from that observed in corresponding embryonic tissues, despite the loss of repressive chromatin modifications at all ERVs. We provide evidence that, upon loss of SETDB1, ERVs are activated in a lineage-specific manner depending on the set of transcription factors available to target proviral regulatory elements. These findings have important implications for genome stability in somatic cells, as well as the interface between epigenetic repression and viral latency.
The histone methyltransferase SETDB1 represses endogenous and exogenous retroviruses in B lymphocytes.
Specimen part
View SamplesGenome stability relies on epigenetic mechanisms that enforce repression of endogenous retroviruses (ERVs). Current evidence suggests that distinct chromatin-based mechanisms repress ERVs in cells of embryonic origin (histone methylation-dominant) versus more differentiated cells (DNA methylation-dominant). However, the latter aspect of this model has not been tested. Remarkably, and in contrast to the prevailing model, we find that repressive histone methylation catalyzed by the enzyme SETDB1 is critical for suppression of specific ERV families and exogenous retroviruses in committed B-lineage cells from adult mice. The profile of ERV activation in SETDB1-deficient B cells is distinct from that observed in corresponding embryonic tissues, despite the loss of repressive chromatin modifications at all ERVs. We provide evidence that, upon loss of SETDB1, ERVs are activated in a lineage-specific manner depending on the set of transcription factors available to target proviral regulatory elements. These findings have important implications for genome stability in somatic cells, as well as the interface between epigenetic repression and viral latency. Overall design: Expression profiling and bisulfite PCR sequencing in Setdb1 C/C and Setdb1 D/D pro-B cells
The histone methyltransferase SETDB1 represses endogenous and exogenous retroviruses in B lymphocytes.
No sample metadata fields
View SamplesE. coli MG155 cells were grown at different grwoth rates in mixed substrate culture. To facilitate different metaoblic status, cells adjust substrate consumption behavior which must be reflected in the gene expression profiles of metablism network. The metabolism network including the substrate transporter systems is our study focus.
Carbon catabolite repression correlates with the maintenance of near invariant molecular crowding in proliferating E. coli cells.
Treatment
View SamplesA diverse antibody repertoire is formed through the rearrangement of V, D, and J segments at the immunoglobulin heavy chain (Igh) loci. The C57BL/6 murine Igh locus has over 100 functional VH gene segments that can recombine to a rearranged DJH. While the non-random usage of VH genes is well documented, it is not clear what elements determine recombination frequency. To answer this question we conducted deep sequencing of 5’-RACE products of the Igh repertoire in pro-B cells, amplified in an unbiased manner. ChIP-seq results for several histone modifications and RNA polymerase II binding, RNA-seq for sense and antisense non-coding germline transcripts, and proximity to CTCF and Rad21 sites were compared to the usage of individual V genes. Computational analyses assessed the relative importance of these various accessibility elements. These elements divide the Igh locus into four epigenetically and transcriptionally distinct domains, and our computational analyses reveal different regulatory mechanisms for each region. Proximal V genes are relatively devoid of active histone marks and non-coding RNA in general, but having a CTCF site near their RSS is critical, suggesting that position near the base of the chromatin loops is important for rearrangement. In contrast, distal V genes have high levels of histone marks and non-coding RNA, which may compensate for their poorer RSS and for being distant from CTCF sites. Thus, the Igh locus has evolved a complex system for the regulation of V(D)J rearrangement that is different for of each the four domains that comprise this locus. Overall design: RNA was extracted from C57BL/6 RAG-/- pro-B cells using Trizol® (Life Technologies Corp., Carlsbad CA) and genomic DNA was eliminated using the genomic DNA wipeout buffer in the QuantiTect Reverse transcription kit (QIAGEN). A final purification of the RNA was performed with the RNeasy kit from QIAGEN. For each sample, 100 ng of total RNA was used to make RNASeq libraries using the NuGEN Encore Complete DR kits following manufacturer''s recommended protocols. Sequencing libraries were gel purified to ensure insert sizes were larger than 100 bp in length and sequenced on an Ilumina HiSeq2000 for 100 bases plus 7 bases for indexing.
Deep sequencing of the murine IgH repertoire reveals complex regulation of nonrandom V gene rearrangement frequencies.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Distinct Gene Regulatory Pathways for Human Innate versus Adaptive Lymphoid Cells.
Specimen part
View SamplesInnate lymphoid cells (ILCs) serve as sentinels in mucosal tissues, sensing release of soluble inflammatory mediators, rapidly communicating danger via cytokine secretion, and functioning as guardians of tissue homeostasis. Although ILCs have been studied extensively in model organisms, little is known about these first responders in humans, especially their lineage and functional kinships to cytokine-secreting T helper cell (Th) counterparts. Here, we report gene regulatory circuitries for four human ILCTh counterparts derived from mucosal environments, revealing that each ILC subset diverges as a distinct lineage from Th and circulating natural killer cells, but shares circuitry devoted to functional polarization with their Th counterparts. Super-enhancers demarcate cohorts of cell identity genes in each lineage, uncovering new modes of regulation for signature cytokines, novel molecules that likely impart important functions to ILCs, and potential mechanisms for autoimmune disease SNP associations within ILCTh subsets.
Distinct Gene Regulatory Pathways for Human Innate versus Adaptive Lymphoid Cells.
Specimen part
View SamplesMost B cell lymphomas arise in the germinal center (GC), where humoral immune responses evolve from potentially oncogenic cycles of mutation, proliferation, and clonal selection. Although lymphoma gene expression diverges significantly from GC-B cells, underlying mechanisms that alter the activities of corresponding regulatory elements (REs) remain elusive. Here we define the complete pathogenic circuitry of human follicular lymphoma (FL), which activates or decommissions transcriptional circuits from normal GC-B cells and commandeers enhancers from other lineages. Moreover, independent sets of transcription factors, whose expression is deregulated in FL, target commandeered versus decommissioned REs. Our approach reveals two distinct subtypes of low-grade FL, whose pathogenic circuitries resemble GC-B or activated B cells. Remarkably, FL-altered enhancers also are enriched for sequence variants, including somatic mutations, which disrupt transcription factor binding and expression of circuit-linked genes. Thus, the pathogenic regulatory circuitry of FL reveals distinct genetic and epigenetic etiologies for GC-B transformation. Overall design: Expression profiles of follicular lymphoma, centrocyte and peripheral blood B cells were generated by deep sequencing, using Illumina Hi-Seq 2000.
NKG2D-NKG2D Ligand Interaction Inhibits the Outgrowth of Naturally Arising Low-Grade B Cell Lymphoma In Vivo.
No sample metadata fields
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