Neural progenitor cells (NPCs) have regenerative capabilities that are activated during inflammation. By measuring the global transcriptome and performing functional studies, we aimed at elucidating if and how NPCs from the non-germinal niche of the spinal cord differ from germinal niche NPCs, here represented by the subventricular zone (SVZ) NPCs. Moreover, we investigated how these cells are affected by chronic inflammation modeled by Experimental Autoimmune Encephalomyelitis (EAE). NPCs were isolated and propagated from the SVZ and cervical, thoracic and caudal regions of the spinal cord from healthy rats and rats subjected to EAE. Using Affymetrix microarray analyses, the global transcriptome was measured in the different NPC populations both in undifferentiated and differentiated cultures. These analyses were paralleled by differentiation studies and quantitative RT-PCR of differentiation-specific genes.
Change of fate commitment in adult neural progenitor cells subjected to chronic inflammation.
Specimen part, Disease, Disease stage
View SamplesThe radiolabelled somatostatin analogue 177Lu-octreotate is a promising treatment option for malignant neuroendocrine tumors that overexpress somatostatin receptors. The human small intestine neuroendocrine tumor cell line GOT1 and Medullary thyroid carcinoma model GOT2 have shown promising treatment response to 177Lu-octreotate in xenografted mice. In clinical studies, however, only low cure rates have been achieved to date. In vitro and preclinical in vivo studies have shown that irradiation can up-regulate the expression of somatostatin receptors and thereby give an increased uptake of 177Lu-octreotate. The cellular processes that underlie positive treatment response to 177Lu-octreotate are otherwise largely unknown. Genome-wide analysis of tumor cell responses in this successful mouse model offers a venue to identify critical treatment parameters and to optimize clinical effectiveness of 177Lu-octreotate therapy. Combining 177Lu-octreotate with other anti-tumor agents has also been proposed as a strategy for optimization. Some studies have shown synergistic effects in tumor cell killing and volume reduction The hedgehog signaling pathway is involved in embryonic development and tissue regeneration and can be/is abnormally activated in various cancers. Inhibition of the hedgehog signaling pathway has yielded promising therapeutic effects on NE tumors and may potentially enhance the effects of 177Lu-octreotate treatment in patients.
Priming increases the anti-tumor effect and therapeutic window of <sup>177</sup>Lu-octreotate in nude mice bearing human small intestine neuroendocrine tumor GOT1.
Time
View SamplesThe radiolabelled somatostatin analogue 177Lu-octreotate is a promising treatment option for malignant neuroendocrine tumors that overexpress somatostatin receptors. The human small intestine neuroendocrine tumor cell line GOT1 and Medullary thyroid carcinoma model GOT2 have shown promising treatment response to 177Lu-octreotate in xenografted mice. In clinical studies, however, only low cure rates have been achieved to date. In xenografted tumors, the human stromal components have been replaced with mouse stroma, which may have an impact in the treatment response of the xenografts.
Priming increases the anti-tumor effect and therapeutic window of <sup>177</sup>Lu-octreotate in nude mice bearing human small intestine neuroendocrine tumor GOT1.
Time
View SamplesThe highly conserved herpesvirus glycoprotein complex, gB/gH-gL, mediates membrane fusion during virion entry and cell-cell fusion. Varicella-zoster virus (VZV) characteristically forms multi-nucleated cells, or syncytia, during the infection of human tissues but little is known about this process. The cytoplasmic domain of VZV gB (gBcyt) has been implicated in cell-cell fusion regulation because a gB[Y881F] substitution causes hyperfusion. The gBcyt regulation is necessary for VZV pathogenesis as the hyperfusogenic mutant gB[Y881F] is severely attenuated in human skin xenografts. In this study, gBcyt regulated fusion was investigated by comparing melanoma cells infected with wild type-like VZV or hyperfusogenic mutants. The gB[Y881F] mutant exhibited dramatically accelerated syncytia formation in melanoma cells caused by fusion of infected cells with many uninfected cells, increased cytoskeleton reorganization and rapid displacement of nuclei to dense central structures when compared to pOka using live cell confocal microscopy. VZV and human transcriptomes were concurrently investigated using RNA-seq to identify viral and cellular responses induced when the gBcyt regulation was disrupted by the gB[Y881F] substitution. The expression of four vital VZV genes, ORF61 and glycoproteins, gC, gE and gI, was significantly reduced at 36 hours post infection for the hyperfusogenic mutants. Importantly, hierarchical clustering demonstrated an association of differential gene expression with dysregulated gBcyt-mediated fusion. A subset of Ras GTPase genes linked to membrane remodeling were upregulated in cells infected with the hyperfusogenic mutants. These data implicate the gBcyt in the regulation gB fusion function that, if unmodulated, triggers cellular processes leading to hyperfusion that attenuates VZV infection. Overall design: Biological duplicates from 3 time points (12, 24 and 36 hours post infection) of uninfected MeWo cells or MeWo cells infected with varicella-zoster virus strain pOka or mutants gB[Y881F], gB[Y920F] or gB[Y881/920F]
Dysregulated Glycoprotein B-Mediated Cell-Cell Fusion Disrupts Varicella-Zoster Virus and Host Gene Transcription during Infection.
Cell line, Subject, Time
View SamplesDendritic cells (DCs) are critical mediators of host defense against bacteria. The goal of this microarray study was to understand the global transcriptional response of bone marrow-derived dendritic cells (BMDCs) upon exposure to live bacteria, to better understand how DCs orchestrate a host-protective immune response. We found that BMDCs upregulate a number of critical immune-related genes upon exposure to live E. coli. Most notably, the gene encoding hepcidin, a critical regulator of mammalian iron homeostasis, was significantly upregulated in BMDCs upon exposure to live bacteria.
Dendritic cell-derived hepcidin sequesters iron from the microbiota to promote mucosal healing.
Specimen part
View SamplesFoxp3+ regulatory T cells (Treg cells) maintain immunological tolerance and their deficiency results in fatal multi-organ autoimmunity. Although heightened T cell receptor (TCR) signaling is critical for the differentiation of Treg cells, the role of TCR signaling in Treg cell function remains largely unknown. Here we demonstrate inducible ablation of the TCR results in Treg cell dysfunction which cannot be attributed to impaired Foxp3 expression, decreased expression of Treg cell signature genes or altered ability to sense and consume interleukin 2. Rather, TCR signaling was required for maintaining the expression of a limited subset of genes comprising 25% of the activated Treg cell transcriptional signature. Our results reveal a critical role for the TCR in Treg cell suppressor capacity.
Continuous requirement for the TCR in regulatory T cell function.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Inflammation-induced repression of chromatin bound by the transcription factor Foxp3 in regulatory T cells.
Specimen part
View SamplesThe transcription factor Foxp3 is indispensable for the ability of regulatory T (Treg) cells to suppress fatal inflammation. Here, we characterized the role of Foxp3 in chromatin remodeling and regulation of gene expression in actively suppressing Treg cells in an inflammatory setting. Although genome-wide Foxp3 occupancy of DNA regulatory elements was similar in resting and in vivo activated Treg cells, Foxp3-bound enhancers were poised for repression only in activated Treg cells. Following activation, Foxp3-bound sites showed reduced chromatin accessibility and selective H3K27 tri-methylation, which was associated with Ezh2 recruitment and downregulation of nearby gene expression. Thus, Foxp3 poises its targets for repression by facilitating formation of repressive chromatin in regulatory T cells upon their activation in response to inflammatory cues.
Inflammation-induced repression of chromatin bound by the transcription factor Foxp3 in regulatory T cells.
Specimen part
View SamplesRNA-Seq analysis of Treg cell subsets isolated from lungs of Il10GFPFoxp3Thy1.1 mice. Thy1.1+ Treg cells were FACS-sorted into IL-10–IL-18R–, IL-10+IL-18R– and IL10–IL-18R+ populations on day 5 following intranasal infection with 0.5 LD50 PR8-OTI influenza virus. Overall design: mRNA profiles of each Thy1.1+ Treg cell population (IL-10–IL-18R–, IL-10+IL-18R– and IL10–IL-18R+) from lungs on day 5 following influenza infection from 5 infected mice, sorted into TRIzol LS reagent.
A Distinct Function of Regulatory T Cells in Tissue Protection.
No sample metadata fields
View SamplesIron is an essential component of the erythrocyte protein hemoglobin and is crucial to oxygen transport in vertebrates. In the steady state, erythrocyte production is in equilibrium with erythrocyte removal1. In various pathophysiological conditions, erythrocyte life span is severely compromised, which threatens the organism with anemia and iron toxicity 2,3. Here we identify anon-demand mechanism specific to the liver that clears erythrocytes and recycles iron. We showthat Ly-6Chigh monocytes ingest stressed and senescent erythrocytes, accumulate in the liver, and differentiate to ferroportin 1 (FPN1)-expressing macrophages that can deliver iron to hepatocytes. Monocyte-derived FPN1+ Tim-4neg macrophages are transient, reside alongside embryonically-derived Tim-4high Kuppfer cells, and depend on Csf1 and Nrf2. The spleenlikewise recruits iron-loaded Ly-6Chigh monocytes, but they do not differentiate into ironrecycling macrophages due to the suppressive action of Csf2, and are instead shuttled to the livervia coordinated chemotactic cues. Inhibiting this mechanism by preventing monocyte recruitment to the liver leads to kidney failure and liver damage. These observations identify the liver as the primary organ supporting emergency erythrocyte removal and iron recycling, and uncover a mechanism by which the body adapts to fluctuations in erythrocyte integrity.
On-demand erythrocyte disposal and iron recycling requires transient macrophages in the liver.
Specimen part
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