Introduction. Factors contributing to kidney transplant fibrosis remain incompletely understoodparticularly in the absence of acute complications.
A meta-analysis of kidney microarray datasets: investigation of cytokine gene detection and correlation with rt-PCR and detection thresholds.
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View SamplesThe aim of this study was to investigate correlations between early subclinical findings (10 and 90 day histology and gene expression data) and late outcomes (transplant glomerulopathy and graft loss) in positive crossmatch kidney transplants (+XMKTx).
Unique molecular changes in kidney allografts after simultaneous liver-kidney compared with solitary kidney transplantation.
Specimen part, Subject
View SamplesThe aim of this study was to investigate correlations between early subclinical findings (10 and 90 day histology and gene expression data) and late outcomes (transplant glomerulopathy and graft loss) in positive crossmatch kidney transplants (+XMKTx).
Early subclinical inflammation correlates with outcomes in positive crossmatch kidney allografts.
Specimen part
View SamplesWe previously observed reduced graft survival for kidney transplants having interstitial fibrosis with subclinical inflammation, but not fibrosis alone, on 1-year protocol biopsy. The current study aimed to determine whether fibrosis with inflammation at 1 year is associated with renal functional decline in a low-risk transplant cohort and to characterize the nature of the inflammation. Subjects were living-donor, tacrolimus/mycophenolate-treated transplant recipients without overt risk factors for reduced graft survival (n=151). Transplants with normal histology (n=86) or fibrosis alone (n=45) on 1-year protocol biopsy had stable renal function between 1 and 5 years, while those having fibrosis with inflammation (n=20) had declining glomerular filtration rate and reduced graft survival. Immunohistochemistry confirmed increased interstitial T-cells and macrophages/dendritic cells in the fibrosis with inflammation group. Gene expression was performed on a subset of biopsies in each group and demonstrated increased expression of transcripts related to innate and cognate immunity in transplants having fibrosis with inflammation. Pathway- and pathological process-specific analyses of microarray profiles revealed that, in fibrosis with inflammation, over-expressed transcripts were enriched for potentially damaging immunological activities including Toll-like receptor signaling, antigen presentation/dendritic cell maturation, interferon gamma-inducible response, cytotoxic T lymphocyte-associated and acute rejection-associated genes. Thus, fibrosis with inflammation in 1-year protocol biopsies is associated with reduced graft survival and function and with a rejection-like gene expression signature even in recipients with no clinical risk for inferior outcome. Early interventions aimed at altering rejection-like inflammation may favor improved long-term KTx survival.
Fibrosis with inflammation at one year predicts transplant functional decline.
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View SamplesWe studied intragraft gene expression profiles of positive crossmatch (+XM) kidney transplant recipients who develop transplant glomerulopathy (TG) and those who do not. Whole genome microarray analysis and quantitative rt-PCR for 30 transcripts were performed on RNA from protocol renal allograft biopsies in 3 groups: 1) +XM/TG+ biopsies before and after TG; 2) +XM/NoTG; and 3) negative crossmatch kidney transplants (control). Microarray comparisons showed few differentially expressed genes between paired biopsies from +XM/TG+ recipients before and after the diagnosis of TG. Comparing +XM/TG+ and control groups, significantly altered expression was seen for 2,447 genes (18%) and 3,200 genes (24%) at early and late time points, respectively. Canonical pathway analyses of differentially expressed genes showed inflammatory genes associated with innate and adaptive immune responses. Comparing +XM/TG+ and +XM/NoTG groups, 3,718 probe sets were differentially expressed but these were over-represented in only 4 pathways. A classic accommodation phenotype was not identified. Using rt-PCR, the expression of inflammatory genes was significantly increased in +XM/TG+ recipients compared to control biopsies and to +XM/NoTG biopsies. In conclusion, pre-transplant DSA results in a gene expression profile characterized by inflammation and cellular infiltration and the majority of XM+ grafts are exposed to chronic injury.
Intragraft gene expression in positive crossmatch kidney allografts: ongoing inflammation mediates chronic antibody-mediated injury.
Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Anti-diabetic rosiglitazone remodels the adipocyte transcriptome by redistributing transcription to PPARγ-driven enhancers.
Cell line, Treatment, Time
View SamplesRosiglitazone (rosi) is a powerful insulin sensitizer, but serious toxicities have curtailed its widespread clinical use. Rosi functions as a high-affinity ligand for PPARg, the adipocyte-predominant nuclear receptor (NR). The classic model, involving binding of ligand to the NR on DNA, explains positive regulation of gene expression, but ligand-dependent repression is not well understood. We have now addressed this issue by studying the direct effects of rosiglitazone on gene transcription, using global run-on sequencing (GRO-seq). Rosi-induced changes in gene body transcription were pronounced after 10 minutes and correlated with steady-state mRNA levels as well as with transcription at nearby enhancers (eRNAs). Upregulated eRNAs occurred almost exclusively at PPARg binding sites, to which rosi treatment recruited the coactivator MED1. By contrast, transcriptional repression by rosi involved a loss of MED1 from eRNA sites devoid of PPARg and enriched for other TFs including AP-1 factors and C/EBPs. Thus, rosi activates and represses transcription by fundamentally different mechanisms that could inform the future development of antidiabetic drugs.
Anti-diabetic rosiglitazone remodels the adipocyte transcriptome by redistributing transcription to PPARγ-driven enhancers.
Cell line, Treatment, Time
View SamplesAcute liver injury is a critical life-threatening event. Common causes are infections, intoxication, and ischemic conditions. The cytokine Interleukin 22 (IL-22) has been implicated in this process. However, the role of IL-22 during acute liver damage is controversial, since both protective and pathogenic properties have been reported. IL-22 binding protein (IL-22BP, IL-22Ra2), a soluble endogenous inhibitor of IL-22, is able to regulate IL-22 activity, and thus might explain some of the controversial findings. Since the role of IL-22BP in liver injury is unknown, we used Il22bp deficient mice and mouse models for acute liver damage to address this point. We found that Il22bp deficient mice were more susceptible to ischemia- and acetaminophen- induced liver damage. Deficiency of Il22bp caused increased hepatic damage and delayed liver regeneration. Using an unbiased approach, we found that IL-22, if uncontrolled in Il22bp deficient mice, induced Cxcl10 expression by hepatocytes, thereby recruiting inflammatory CD11b+Ly6C+ monocytes into the liver upon liver damage. Accordingly, neutralization of Cxcl10 reversed the increased disease susceptibility of Il22bp deficient mice. In conclusion, our data suggest dual functions of IL-22 in acute liver damage, and highlight the need to control IL-22 activity via IL-22BP. Overall design: RNA sequencing of RNA isolated from liver tissue from mice that underwent liver reperfusion treatment (IR) or sham surgery, in triplicate for three genotypes (Wt, Il22-/- and Il22bp-/-).
A Protective Function of IL-22BP in Ischemia Reperfusion and Acetaminophen-Induced Liver Injury.
Specimen part, Treatment, Subject
View SamplesPurpose: The goal of this study was to identify differential splicing events in the Drosophila eye during aging. Overall design: Method: RNA extracted from dissected eye tissue of flies aged 10 and 40 days post-eclosion was used to generate cDNA libraries using NuGen Ovation Drosophila RNA seq system. Samples were sequenced using Illumina HiSeq2500 next generation sequencer (three biological replicates per time point).
Proper splicing contributes to visual function in the aging Drosophila eye.
Sex, Age, Specimen part, Subject
View SamplesWe developed a general approach to small molecule library screening called GE-HTS (Gene Expression-Based High Throughput Screening) in which a gene expression signature is used as a surrogate for cellular states and applied it to the identification of compounds inducing the differentiation of acute myeloid leukemia cells. In screening 1,739 compounds, we identified 8 that reliably induced the differentiation signature, and furthermore yielded functional evidence of bona fide differentiation.
Gene expression-based high-throughput screening(GE-HTS) and application to leukemia differentiation.
No sample metadata fields
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