The molecular mechanism(s) leading to Purkinje neuron loss in the neurodegenerative disorder Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS) are limited by the complex morphology of this cell type. Purkinje neurons are notoriously difficult to isolate and maintain in culture presenting considerable difficultly to identify molecular changes in response to riboCGG repeat-containing mRNA that induces neurotoxicity in FXTAS. Several studies have uncovered a number of RNA binding proteins involved in translation that aberrantly interact with the toxic RNA; however, whether these interactions alter the translational profile of cells has not been investigated. Here we employ bacTRAP translational profiling to demonstrate that Purkinje neurons ectopically expressing 90 CGG repeats exhibit a dramatic change in their translational profile even prior to the onset of riboCGG-induced phenotypes. This approach identified nearly 500 transcripts that are differentially associated with ribosomes in r(CGG)90-expressing mice. Functional annotation cluster analysis revealed broad ontologies enriched in the r(CGG)90 list, including RNA binding and response to stress. Intriguingly, a transcript for the Tardbp gene, implicated in a number of other neurodegenerative disorders, exhibits altered association with ribosomes in the presence of r(CGG)90 repeats. We therefore tested and showed that reduced association of Tardbp mRNA with the ribosomes results in a loss of TDP-43 protein expression in r(CGG)90expressing Purkinje neurons. Furthermore, we showed that TDP-43 could modulate the rCGG repeat-mediated toxicity in a Drosophila model that we developed previously. These findings together suggest translational dysregulation may be an underlying mechanism of riboCGG-induced neurotoxicity and provide insight into the pathogenicity of FXTASBAC-trap studies of Purkinje cels in normal and mutant mice
CGG repeats in RNA modulate expression of TDP-43 in mouse and fly models of fragile X tremor ataxia syndrome.
Age, Specimen part
View SamplesThis study provides the dectin-1 and NFAT responsive genes for 2h and 4h of curdlan treatment.
NFATc2 mediates epigenetic modification of dendritic cell cytokine and chemokine responses to dectin-1 stimulation.
Specimen part
View SamplesDendritic cells (DCs) are crucial for sensing pathogens and triggering immune response. GM-CSF myeloid dendritic cells (GM-DCs) secrete several cytokines including IL-2 upon activation by pathogen associated molecular pattern (PAMP) ligands. DC IL-2 has been shown to be important for innate and adaptive immune responses, however its importance in DC physiology has never been demonstrated. This is due to ambiguity in expression of the CD122 subunit of the IL-2 trimeric receptor complex crucial for signaling. We show here that autocrine IL-2 signaling is functional in GM-DCs in early time window of stimulation with PAMPs. IL-2 signaling selectively activates the JAK/STAT5 pathway by assembling holo-receptor complexs at the cell surface. Autocrine IL-2 signaling inhibits survival of PAMP matured GM-DCs which is crucial for maintaining immune tolerance and preventing autoimmunity. Our findings suggest immune regulation by a novel autocrine signaling pathway that can potentially be exploited in DC immunotherapy.
Dendritic cell derived IL-2 inhibits survival of terminally mature cells via an autocrine signaling pathway.
Specimen part
View SamplesCharacterization of colon CD11chigh/MHCII+ myeloid cell subsets
Intestinal CD103(+)CD11b(-) dendritic cells restrain colitis via IFN-γ-induced anti-inflammatory response in epithelial cells.
No sample metadata fields
View SamplesTreatment of post-transplant patients with immunosuppressive drugs targeting the calcineurin-NFAT pathway, such as Cyclosporine A or Tacrolimus, are commonly associated with a higher incidence of opportunistic infections, such as Aspergillus fumigatus, which can lead to severe life-threating conditions. A component of the A. fumigatus cell wall, -glucan, is recognized by dendritic cells via the Dectin-1 receptor, triggering downstream signaling that leads to calcineurin-NFAT binding, NFAT translocation, and transcription of NFAT-regulated genes. Here, we address the question of whether calcineurin signaling in CD11c-expressing cells, such as DCs, has a specific role in the innate control of A. fumigatus. Impairment of calcineurin in CD11c-expressing cells (CD11ccrecnb1loxP) significantly increased susceptibility to systemic A. fumigatus infection and to intranasal infection in irradiated mice undergoing bone marrow transplant. Global expression profiling of bone marrow-derived DCs identified calcineurin-regulated processes in the immune response to infection, including expression of pentraxin-3, an important anti-fungal defense protein. These results suggest that calcineurin inhibition directly impairs important immunoprotective functions of myeloid cells, as shown by the higher susceptibility of CD11ccrecnbloxP mice in models of systemic and invasive pulmonary aspergillosis, including after allogeneic bone marrow transplantation. These findings are relevant to the clinical management of transplant patients with severe Aspergillus infections.
Impaired calcineurin signaling in myeloid cells results in downregulation of pentraxin-3 and increased susceptibility to aspergillosis.
Specimen part
View SamplesMonocytes, neutrophils and tissue resident macropahges of colon lamina propia are compared to their intratumoral counterparts found in colon adenomas Overall design: Different myeloid subpopulations were isolated from healthy colon lamina propria and colon adenomas, sorted by flow cytometry and processed for RNA.
The tumour microenvironment creates a niche for the self-renewal of tumour-promoting macrophages in colon adenoma.
Specimen part, Cell line, Subject
View SamplesMHC class I-related molecule MR1 presents riboflavin-derived microbial metabolites and folate-derivatives to mucosal-associated invariant T cells, but it is unknown whether MR1 can bind alternative antigens that stimulate other T cell lineages. Here we report that human T cells displaying diverse TCR-a and ß chains recognize MR1-expressing cells in the absence of microbial ligands and respond to recombinant MR1 molecules loaded with antigens extracted from stimulatory targets. Transcriptome analysis revealed functional heterogeneity of MR1-reactive T cells (MR1T cells), which displayed differential expression of various transcription factors regulating T cell polarization, proliferation and apoptosis. Accordingly, MR1T cells displayed multiple profiles of chemokine receptor expression and secreted variable combinations of cytokines and growth factors, suggesting a diversity of immunological roles across numerous tissues. Functionally, MR1T cells were capable of inducing dendritic cell maturation and stimulating anti-microbial responses in intestinal epithelial cells. These data demonstrate that MR1 presents endogenous antigens to a novel population of functionally diverse human T cells. Overall design: mRNA profiles of two representative MR1T cell clones in resting (not exposed to antigen) and activated (stimulated with A375-MR1 antigen target cells and activated) states
Functionally diverse human T cells recognize non-microbial antigens presented by MR1.
Specimen part, Subject
View SamplesComplex regulatory mechanisms control continuous maintenance of myeloid progenitors and renewal of differentiated cells. Transcription factors play a important role in these processes. Here we report that the activation the calcineurin-NFAT signaling pathway inhibit the proliferation of myeloid granulocyte-monocyte progenitor (GMP). Myeloid progenitor subtypes possessed different susceptibilities to Ca2+ flux induction and consequently differential engagement of the calcineurin-NFAT pathway. This study show that inhibition of the calcineurin-NFAT pathway enhanced proliferation of GMPs both in vivo and in vitro. The calcineurin-NFAT signaling in GMPs is initiated through Flt3-L. The inhibition of the calcineurin-NFAT pathway altered the expression of the cell cycle regulation genes CDK4, CDK6, and CDKN1A, thus enabling faster cell cycle progression. The extensive use of NFAT inhibitors in the clinic should take into account that, in addition to the immunosuppression role in lymphoid cells, these NFAT inhibitors also affect the maintenance of the myeloid compartment.
Calcium and calcineurin-NFAT signaling regulate granulocyte-monocyte progenitor cell cycle via Flt3-L.
Specimen part
View SamplesWe performed RNA-Seq transcriptome profiling on 29 immune cell types consituting peripheral blood mononuclear cells (PBMCs) sorted from 4 Singaporean-Chinese individuals (S4 cohort). We also performed RNA-Seq and microarray transcriptome profiling of PBMCs from an extended cohort of 13 individuals (S13 cohort). The data was used first to characterize the transcriptomic signatures and relationships among the 29 immune cell types. Then we explored the difference in mRNA composition in terms of transcripts proportions and abundance. Lastly, we performed deep deconvolution for both microarray and RNA-Seq technologies. Overall design: Total RNA of 29 immune cell types (from 4 individuals) and peripheral blood mononuclear cells (PBMCs, from 13 individuals) was extracted for gene expression profiling. The 13 PBMCs samples were processed with both microarray and RNA-Seq platforms.
RNA-Seq Signatures Normalized by mRNA Abundance Allow Absolute Deconvolution of Human Immune Cell Types.
Sex, Specimen part, Disease, Subject
View SamplesFollowing combined stimulation through Toll-like receptor (TLR)-9 and the B-cell receptor (BCR), human B cells were sorted based on IL-10 expression.
Human regulatory B cells combine phenotypic and genetic hallmarks with a distinct differentiation fate.
Specimen part
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