Mouse thymocytes can be classified into four major subsets based on expression of CD4 and CD8 co-receptors. CD4-CD8- (double negative, DN) cells become CD4+CD8+ (double positive, DP) cells following productive T cell receptor (TCR) beta chain rearrangement. A small proportion of DP cells are selected through interaction of clonal TCRalpha/beta and MHC self peptide complex expressed on thymic stromal cells. DP cell expressing MHC class I-restricted TCR become CD4-CD8+ cells, which will finally differentiate into cytotoxic T cells, while MHC class II restricted selection generates CD4+CD8- helper lineage T cells.
Transcription factor AP4 modulates reversible and epigenetic silencing of the Cd4 gene.
Specimen part
View SamplesDendritic cells (DC) serve a key function in host defense, linking innate detection of microbes to the activation of pathogen-specific adaptive immune responses. Whether there is cell-intrinsic recognition of HIV-1 by host innate pattern-recognition receptors and subsequent coupling to antiviral T cell responses is not yet known. DC are largely resistant to infection with HIV-1, but facilitate infection of co-cultured T-helper cells through a process of trans-enhancement. We show here that, when DC resistance to infection is circumvented, HIV-1 induces DC maturation, an antiviral type I interferon response and activation of T cells. This innate response is dependent on the interaction of newly-synthesized HIV-1 capsid (CA) with cellular cyclophilin A (CypA) and the subsequent activation of the transcription factor IRF3. Because the peptidyl-prolyl isomerase CypA also interacts with CA to promote HIV-1 infectivity, our results suggest that CA conformation has evolved under opposing selective pressures for infectivity versus furtiveness. Thus, a cell intrinsic sensor for HIV-1 exists in DC and mediates an antiviral immune response, but it is not typically engaged due to absence of DC infection. The virulence of HIV-1 may be related to evasion of this response, whose manipulation may be necessary to generate an effective HIV-1 vaccine.
A cryptic sensor for HIV-1 activates antiviral innate immunity in dendritic cells.
Specimen part
View SamplesIn skeletal muscle, the pattern of electrical activity regulates the expression of proteins involved in synaptic transmission, contraction and metabolism. Disruptions in electrical activity, resulting from prolonged bed-rest, cast-immobilization or trauma, inevitably lead to muscle atrophy. The mechanisms that regulate muscle atrophy are poorly understood, but it seems likely that changes in gene expression play a key role in initiating and maintaining a muscle atrophy program. Previously, we found that Runx1, a transcription factor previously termed AML1, was substantially induced in muscle following denervation. More recently, we sought to determine whether this increase in Runx1 expression may be causally related to the morphological changes in skeletal muscle that accompany muscle disuse, notably muscle atrophy. We found that Runx1 is indeed required to sustain muscle and to minimize atrophy following denervation. Experiments described here are designed to identify the genes that are regulated by Runx1 in skeletal muscle with the particular goal of identifying genes that regulate muscle atrophy.
Runx1 prevents wasting, myofibrillar disorganization, and autophagy of skeletal muscle.
No sample metadata fields
View SamplesGPR15 is an orphan G-protein coupled receptor and its expression is abundant among T cells in the large intestine lamina propria.
GPR15-mediated homing controls immune homeostasis in the large intestine mucosa.
Specimen part
View SamplesTranscriptional regulatory networks (TRNs) provide insight into cellular behavior by describing interactions between transcription factors (TFs) and their gene targets. The Assay for Transposase Accessible Chromatin (ATAC)-seq, coupled with transcription-factor motif analysis, provides indirect evidence of chromatin binding for hundreds of TFs genome-wide. Here, we propose methods for TRN inference in a mammalian setting, using ATAC-seq data to influence gene expression modeling. We rigorously test our methods in the context of T Helper Cell Type 17 (Th17) differentiation, generating new ATAC-seq data to complement existing Th17 genomic resources (plentiful gene expression data, TF knock-outs and ChIP-seq experiments). In this resource-rich mammalian setting our extensive benchmarking provides quantitative, genome-scale evaluation of TRN inference combining ATAC-seq and RNA-seq data. We refine and extend our previous Th17 TRN, using our new TRN inference methods to integrate all Th17 data (gene expression, ATAC-seq, TF KO, ChIP-seq). We highlight new roles for individual TFs and groups of TFs (“TF-TF modules”) in Th17 gene regulation. Given the popularity of ATAC-seq (a widely adapted protocol with high resolution and low sample input requirements), we anticipate that application of our methods will improve TRN inference in new mammalian systems and be of particular use for rare, uncharacterized cell types. Overall design: Gene expression (RNA-seq) of naive and Th17- and Th0-polarized CD4 T Cells
Leveraging chromatin accessibility for transcriptional regulatory network inference in T Helper 17 Cells.
Specimen part, Cell line, Subject
View SamplesUnperturbed cholesterol homeostasis is important for normal development and sexual maturation in mice. Cyp51 is the rate limiting step in the post-lanosteorl part of cholesterol biosynthesis. Unlike the full body knockout, hepatocyte specific Cyp51 knockout mice survive throughout adulthood, however their livers are severly affected. Several of the hepatocyte specific Cyp51 knockout mice develop severe liver injury or die prior to reaching adulthood (from 4-10 weeks of age; designated as runts). We aim to uncover the timing and the mechanistic background governing the liver damage and sex differences.
Disrupting Hepatocyte Cyp51 from Cholesterol Synthesis Leads to Progressive Liver Injury in the Developing Mouse and Decreases RORC Signalling.
Sex, Specimen part
View SamplesHere we describe microRNA profiling of a single differentiation pathway from the stem cell through to terminally differentated mature cells. Overall design: Populations corresponding to distinct stages in T lymphocyte development, from the hematopoietic stem cell-enriched Lin-Sca+Kit+ population through to mature CD4+ and CD8+ T cells were FACS-sorted to purity from the bone marrow and thymus of C57BL/6 mice. Total RNA was extract from each population from which microRNA sequencing libraries were constructed.
Dynamic microRNA gene transcription and processing during T cell development.
Specimen part, Cell line, Subject
View SamplesPurpose: The goals of this study are to compare in vitro polarized T helper 17 cell transcriptome profiling (RNA-seq) in the presence or absence of recombinant murine SAA1 Methods: Th17 mRNA profiles of 96hrs in vitro cultured T helper 17 cells treated with vehicle or recombinant murine SAA1 were generated by deep sequencing, using Illumina RapidRun. The sequence reads that passed quality filters were analyzed at the transcript isoform level with two methods: Burrows–Wheeler Aligner (BWA) and TopHat followed by CuffDiff. qRT–PCR validation was performed using SYBR Green assays. Results: 177 genes were changed more than 2 folds in the presence of recombinant murine SAA1. Conclusions: Our study suggest that SAA1 could augment subset of Th17 transcription program in vitro. Overall design: mRNA profiles of 48hr in vitro cultured Th17 from wild type (WT) mice were generated by deep sequencing using Illumina RapidRun.
An IL-23R/IL-22 Circuit Regulates Epithelial Serum Amyloid A to Promote Local Effector Th17 Responses.
No sample metadata fields
View SamplesHere we show the microRNA genes can been very large and displaying many summarizing structural characteristics Overall design: MicroRNA biogenesis was ablated in CD4+ and CD8+ by deleted Rnasen gene (encoding Drosha). Poly A RNAs were extracted and analyzed by ultra high throughput sequencing
Dynamic microRNA gene transcription and processing during T cell development.
Specimen part, Cell line, Subject
View SamplesPurpose: The goals of this study are to compare mRNAs expressed by Th17 cells and ILC3s in small intestine of lamina propria of mice. Methods: Small intestine were digested with collagenase, dispase, and DNase. Percoll enriched lamina propria Th17 and ILCs sorted by BD ARIA II. Total RNA were harvested and sequencing were performe. The sequence reads that passed quality filters were analyzed at the transcript isoform level with two methods: Burrows–Wheeler Aligner (BWA) and TopHat followed by CuffDiff. qRT–PCR validation was performed using SYBR Green assays. Results: Small intestine Th17 cells and ILCs exhibit differential gene expression profiles. Overall design: compare mRNAs expressed by Th17 cells and ILC3s in small intestine of lamina propria of mice.
An IL-23R/IL-22 Circuit Regulates Epithelial Serum Amyloid A to Promote Local Effector Th17 Responses.
No sample metadata fields
View Samples