During activation, T cells integrate multiple signals from APCs and cytokine milieu. The blockade of these signals can have clinical benefits as exemplified by CTLA4-Ig, which blocks interaction of B7 co-stimulatory molecules on APCs with CD28 on T cells. Variants of CTLA4-Ig, abatacept and belatacept are FDA approved as immunosuppressive agents in arthritis and transplantation whereas murine studies suggested that CTLA4-Ig can be beneficial in a number of other diseases. However, detailed analysis of human CD4 cell hyporesponsivness induced by CTLA4-Ig has not been performed. Herein, we established a model to study effect of CTLA4-Ig on the activation of human naïve T cells in a human mixed lymphocytes system. Comparison of human CD4 cells activated in the presence or absence of CTLA4-Ig, showed that co-stimulation blockade during TCR activation does not affect NFAT signaling but results in decreased activation of NF-kB and AP-1 transcription factors followed by profound decrease in proliferation and cytokine production. The resulting T cells become hyporesponsive to secondary activation and, although capable of receiving TCR signals, fail to proliferate or produce cytokines, demonstrating properties of anergic cells. However, unlike some models of T cell anergy, these cells did not possess increased levels of TCR signaling inhibitor CBLB. Rather, the CTLA4-Ig induced hyporesponsiveness was associated with an elevated level of p27kip1 cyclin-dependent kinase inhibitor. Overall design: Time series. Human resting and activated T cell dUTP mRNA-Seq profiles were generated on Illumina HiSeq2500
Functional characterization of human T cell hyporesponsiveness induced by CTLA4-Ig.
No sample metadata fields
View SamplesIn most metazoan nuclei, heterochromatin is located at the nuclear periphery in contact with the nuclear lamina, which provides mechanical stability to the nucleus. We show that in cultured cells, chromatin de-compaction by the nucleosome binding protein HMGN5 decreases the sturdiness, elasticity, and rigidity of the nucleus. Mice overexpressing HMGN5, either globally or only in the heart, are normal at birth but develop hypertrophic heart with large cardiomyoctyes, deformed nuclei and disrupted lamina, and die of cardiac malfunction. Chromatin de-compaction is seen in cardiomyocytes of newborn mice but misshaped nuclei with disrupted lamina are seen only in adult cardiomyocytes, suggesting that loss of heterochromatin diminishes the ability of the nucleus to withstand the mechanical forces of the contracting heart. Thus, heterochromatin enhances the ability of the nuclear lamina to maintain the sturdiness and shape of the eukaryotic nucleus; a structural role for chromatin that is distinct from its genetic functions.
Chromatin decompaction by the nucleosomal binding protein HMGN5 impairs nuclear sturdiness.
Specimen part
View SamplesHMGN (high mobility group N) is a family of intrinsically disordered nuclear proteins that binds to nucleosomes, alters the structure of chromatin and affects transcription. A major unresolved question is the extent of functional specificity, or redundancy, between the various members of the HMGN protein family.
Effects of HMGN variants on the cellular transcription profile.
Specimen part
View SamplesEosinophils are major effector cells in type 2 inflammatory responses and become activated in response to IL-4 and IL-33, yet the molecular mechanism remains unclear. We examined the direct effect of these cytokines on eosinophils and demonstrated that murine eosinophils respond to IL-4 and IL-33 by phosphorylation of STAT-6 and NFkB, respectively. RNA sequencing analysis of murine eosinophils indicated that IL-33 regulates 519 genes, whereas IL-4 regulates only 28 genes, including 19 IL-33-regulated genes. Interestingly, IL-33 induced eosinophil activation via two distinct mechanisms, IL-4 independent and IL-4 secretion/auto-stimulation dependent. Anti-IL-4 or anti-IL-4Ra antibody-treated eosinophils, as well as Il4- or Stat6-deficient eosinophils, had attenuated protein secretion of a subset of IL-33-induced genes, including Retnla and Ccl17. However, the induction of most IL-33-regulated transcripts (e.g. Il6 and Il13) was IL-4 independent and blocked by NFkB inhibition. Indeed, IL-33 induced the rapid release of pre-formed IL-4 protein from eosinophils by an NFkB-dependent mechanism. Thus, we have identified a novel activation pathway in murine eosinophils that is induced by IL-33 and differentially dependent upon IL-4. These data suggest that IL-4 plays a critical role in auto-amplification of IL-33-induced eosinophil activation and could be a potential target for therapeutic approaches in IL-33-related eosinophil-associated diseases. Overall design: Low density bone marrow derived murine eosinophils were generated in culture over the period of 14 days. Eosinophils were activated by either IL-33 or IL-4 at 10 ng/ml for 1hr and 4hr. RNA was collected and subjected to next generation sequencing.
IL-33 markedly activates murine eosinophils by an NF-κB-dependent mechanism differentially dependent upon an IL-4-driven autoinflammatory loop.
Specimen part, Cell line, Subject
View SamplesWe used RNA sequencing to identify differentially expressed genes during esophageal epithelial differentiation and in the presence of interleukin 13 using an air-liquid interface culture system. Overall design: RNA sequencing was performed on a human esophageal epithelial cell line (EPC2-hTERT) grown submerged (day 8) or at the air-liquid interface (ALI) (day 14, untreated or treated with interleukin 13 [100 ng/mL])
Eosinophilic esophagitis-linked calpain 14 is an IL-13-induced protease that mediates esophageal epithelial barrier impairment.
No sample metadata fields
View SamplesChromatin architectural protein NSBP1/HMGN5 belongs to the family of HMGN proteins which specifically interact with nucleosomes via Nucleosome Binding Domain, unfold chromatin and affect transcription. Mouse NSBP1 is a new and uncharacterized member of HMGN protein family. NSBP1 is a nuclear protein which is localized to euchromatin, binds to linker histone H1 and unfolds chromatin.
The interaction of NSBP1/HMGN5 with nucleosomes in euchromatin counteracts linker histone-mediated chromatin compaction and modulates transcription.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Critical Role of STAT5 transcription factor tetramerization for cytokine responses and normal immune function.
Specimen part, Treatment, Time
View SamplesCytokine-activated STAT proteins dimerize and bind to high-affinity motifs, and N-terminal domain-mediated oligomerization of dimers allows tetramer formation and binding to low-affinity tandem motifs, but the functions of dimers versus tetramers are unknown. We generated Stat5a and Stat5b double knock-in (DKI) N-domain mutant mice that form dimers but not tetramers, identified cytokine-regulated genes whose expression required STAT5 tetramers, and defined consensus motifs for dimers versus tetramers. Whereas Stat5- deficient mice exhibited perinatal lethality, DKI mice were viable, indicating that STAT5 dimers were sufficient for survival. Nevertheless, STAT5 DKI mice had fewer CD4+CD25+ T cells, NK cells, and CD8+ T cells, with impaired cytokine-induced proliferation and homeostatic proliferation of CD8+ T cells. DKI CD8+ T cell proliferation following viral infection was diminished and DKI Treg cells did not efficiently control colitis. Thus, tetramerization of STAT5 is dispensable for survival but is critical for cytokine responses and normal immune function.
Critical Role of STAT5 transcription factor tetramerization for cytokine responses and normal immune function.
Specimen part, Treatment, Time
View SamplesRetinoic acid (RA), the main active vitamin A metabolite, controls multiple biological processes such as cell proliferation and differentiation through genomic programs and kinase cascades activation. Several breast cancer cells respond to the antiproliferative effects of RA, but others are RA-resistant. In several cases resistance has been correlated to the amplification of the erb-b2 receptor tyrosine kinase 2 (ERBB2) gene, but the overall signaling and transcriptional pathways that are altered in such cells have not been elucidated. Here we compared two human breast cancer cell lines, the MCF7 cell line, which responds to the antiproliferative action of RA and the BT474 cell line, which is RA-resistant subsequent to ERBB2 amplification in a large-scale analysis of the phosphoproteins and in a genome-wide analysis of the RA-regulated genes. Using high-resolution nano-LC-LTQ-Orbitrap mass spectrometry associated to phosphopeptide enrichment, we found that several proteins involved in signaling and in transcription, are differentially phosphorylated after RA addition. The paradigm of these proteins is the RA receptor a (RARa), which was phosphorylated in MCF7 cells but not in BT474 cells. The panel of the RA-regulated genes was also different. Overall our results indicate that ERBB2 amplification interferes with the ability of RA to activate kinases with consequences on the phosphorylation of several proteins involved in transcription and thus on gene expression. Overall design: Two human breast cancer cell lines were compared for their repertoire of genes regulated by retinoic acid (RA): the RA sensitive MCF7 cell line and the RA resistant B7474 cell line
Phosphoproteome and Transcriptome of RA-Responsive and RA-Resistant Breast Cancer Cell Lines.
Specimen part, Cell line, Treatment, Subject
View SamplesGene expression profiling of 82 patients with cervical cancer was performed. The expression data were correlated with copy number alterations of the same patients, as assessed with array CGH in a separate study, in order to identify drivers of cervical cancer carcinogenesis.
Gene network reconstruction reveals cell cycle and antiviral genes as major drivers of cervical cancer.
Specimen part
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