Mouse primary astrocytes: LCN2 protein treated vs. control
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE15667 | GEO | 2012/06/30
SECONDARY ACCESSION(S): PRJNA115615
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptional profiling of mouse primary astrocytes comparing control untreated astrocytes with astrocytes treated with recombinant LCN2 protein (10 micro gram/ml). Goal was to determine the effects of LCN2 treatment on global gene expression in astrocytes. A secreted protein lipocalin-2 (LCN2) has been implicated in diverse cellular processes including cell morphology and migration. We have previously demonstrated that lcn2 mediates reactive astrocytosis. In order to further understand the role of lcn2 in the CNS, astrocyte transcriptome was analyzed following LCN2 treatment. Chemokines were the major group of genes upregulated by LCN2. Two-condition experiment, control untreated astrocytes vs. LCN2 protein treated astrocytes. Biological replicates: 1 control replicates, 1 treated replicates.
2012-06-29 | E-GEOD-15667 | biostudies-arrayexpress
Project description:Staphylococcus (S.) epidermidis is one of the most common nosocomial coagulase-negative staphylococci infections in preterm infants. The clinical signs of infection are often unspecific and identification of novel markers to complement the current diagnosis is needed. In this study, we investigated proteomic alterations in the neonatal mouse brain following S. epidermidis infection and in the blood in preterm infants. We identified lipocalin 2 (LCN2) as a crucial protein associated with cerebrovascular changes and astrocyte reactivity in mice. While astrocytes were activated in S. epidermidis infected mice, LCN2 protein expression in the brain was associated with endothelial cells but not astrocyte reactivity. By combining weighted gene co-expression analysis and differential expression approaches, we further identified that LCN2 protein was linked to blood C-reactive protein levels in a cohort of preterm infants born <28 weeks of gestation. Blood LCN2 levels were associated with similar alterations of cytokines and chemokines in both infected mice and human preterm infants with increased levels of CRP. The present experimental and clinical study indicates that LCN2 might be a suitable additional marker of preterm infection/inflammation associated with cerebrovascular changes and neuroinflammation.
2023-10-24 | PXD041926 | Pride
Project description:Iron is essential for many cellular processes and is required by bacteria for replication. To acquire iron from the host, pathogenic Gram-negative bacteria secrete siderophores, including Enterobactin (Ent). However, Ent is bound by the host protein Lipocalin 2 (Lcn2), preventing bacterial reuptake of aferric or ferric Ent. In two experiments we treated A549 (lung cancer cell line) cells with Lcn2, Ent, and iron, alone and in combination. In experiment 1, biological duplicates of 4 conditions were used: PBS control, Lcn2, Lcn2+Ent, and Lcn2+Ent+iron. In experiment 2, 4 biological replicates of 4 conditions were used: PBS control, Ent, iron, and Ent+iron. Targets made from the samples were hybridized to Affymetrix Human Gene 1.0 ST arrays to measure transcript abundances. The RMA algorithm was used to estimate transcript levels. Replicate samples were exchangeable, so we fit one-way ANOVA models to log2-transformed data separately to each experiment, and tested for pairwise differences between groups in each experiment, as well as asking if the Ent vs. PBS differences were larger or smaller than the Ent+iron vs. iron differences (Ent by iron interactions). We report results for 29096 probe-sets that were not annotated as positive or negative controls on the array. A supplementary Excel workbook is provided that contains the estimated expression level, some probe-set annotation, and simple statistical analysis for each probe-set. It may be convenient for some users, however obtaining newer probe-set annotation may be advisable. A549 (ATCC CCL-185) cells, a human type II pneumocyte cell line, were cultured in F12K (Invitrogen, Carlsbad, CA) media supplemented with 10% fetal bovine serum (Invitrogen) and 1:100 penicillin streptomycin (Invitrogen). 24-well plates were seeded with A549 cells at a concentration of 35000 cells/well. After two days, cells were weaned from serum and antibiotics overnight. Cells were then stimulated overnight with the indicated combinations of 50 uM Ferric ammonium citrate (FAC) (Sigma, St. Louis, MO), 50 um Ent (Sigma or EMC Microcollections, Tubingen, Germany), and/or 25 uM lipocalin 2 (Lcn2) in F12K media lacking serum or antibiotics. Prior to incubation with cells, siderophore-Lcn2 complexes were prepared by sequential incubation at room temperature of FAC and Ent for 30 minutes followed by addition of Lcn2 and incubation for an additional 30 minutes. In experiment 1, 2 biological replicates of each of these 4 conditions were grown: PBS, 25 uM lipocalin 2 (Lcn2), a combination of 25 uM Lcn2 with 50 uM Enterobactin (Ent), and a combination of Lcn2, Ent and 50 uM Ferric Ammonium Citrate (FAC). In experiment 2, 4 biological replicates of each of these 4 conditions were grown: PBS, 50 uM Ent, 50 uM FAC, and a combination of 50 uM Ent and 50 uM FAC. Cells were harvested and RNA was extracted using an miRNeasy Mini Kit (Qiagen). Biotinylated cDNA targets were prepared according to the Ambion WT expression kit protocol from 150 ng total RNA. There are no batches within each experiment - the samples in each group are exchangeable. Targets were hybridized to Affymetrix Human Gene 1.0 ST arrays. Arrays were scanned and quantified by usual procedures, and transcript abundances for 29096 non-control probe-sets estimated by an RMA algorithm.
2014-07-03 | E-GEOD-54962 | biostudies-arrayexpress
Project description:Iron is essential for many cellular processes and is required by bacteria for replication. To acquire iron from the host, pathogenic Gram-negative bacteria secrete siderophores, including Enterobactin (Ent). However, Ent is bound by the host protein Lipocalin 2 (Lcn2), preventing bacterial reuptake of aferric or ferric Ent. In two experiments we treated A549 (lung cancer cell line) cells with Lcn2, Ent, and iron, alone and in combination. In experiment 1, biological duplicates of 4 conditions were used: PBS control, Lcn2, Lcn2+Ent, and Lcn2+Ent+iron. In experiment 2, 4 biological replicates of 4 conditions were used: PBS control, Ent, iron, and Ent+iron. Targets made from the samples were hybridized to Affymetrix Human Gene 1.0 ST arrays to measure transcript abundances. The RMA algorithm was used to estimate transcript levels. Replicate samples were exchangeable, so we fit one-way ANOVA models to log2-transformed data separately to each experiment, and tested for pairwise differences between groups in each experiment, as well as asking if the Ent vs. PBS differences were larger or smaller than the Ent+iron vs. iron differences (Ent by iron interactions). We report results for 29096 probe-sets that were not annotated as positive or negative controls on the array. A supplementary Excel workbook is provided that contains the estimated expression level, some probe-set annotation, and simple statistical analysis for each probe-set. It may be convenient for some users, however obtaining newer probe-set annotation may be advisable.
2014-07-03 | GSE54962 | GEO
Project description:Effect of recombinant murine Lipocalin-2 (LCN2) on murine macrophages
| PRJNA935307 | ENA
Project description:NFAT1 is a transcription factor that elicits breast carcinoma cells to become invasive, contributing thus to formation of metastases. The molecular mechanisms by which NFAT1 operates in this respect are still poorly known. Here, we report that NFAT1 increases Lipocalin 2 (LCN2) mRNA and protein expression by binding to specific sites in the LCN2 gene promoter region. We show that the LCN2 protein is required downstream of NFAT1 to increase breast cancer cell invasion. We demonstrate that the NFAT1/LCN2 axis is sufficient to regulate expression of the TNF-like receptor TWEAKR at the RNA level and of its ligand, TWEAK, at the protein level. We show, however, that TWEAKR mediates an anti-invasive effect in breast cancer cells whereas, depending on LCN2 expression, TWEAK has either anti- and pro-invasive capacities. Thus, we identify LCN2 and TWEAKR/TWEAK as critical downstream effectors of NFAT1 to regulate breast cancer cell motility and invasive capacity.
2015-05-31 | GSE38369 | GEO
Project description:Astrocytes were purified from fetal and adult human brain tissue using an immunopanning method with the HepaCAM antibody. Samples were taken from otherwise 'healthy' pieces of tissue, unless otherwise specified. 6 fetal astrocyte samples, 12 adult astrocyte samples, 8 GBM or sclerotic hippocampal samples, 4 whole human cortex samples, 4 adult mouse astrocyte samples, and 11 human samples of other purified CNS cell types
2015-12-11 | E-GEOD-73721 | biostudies-arrayexpress
Project description:Lipocalin 24p3 (24p3) is a neutrophil secondary granule protein. 24p3 is also a siderocalin, which binds several bacterial siderophores. It was therefore proposed that synthesis and secretion of 24p3 by stimulated macrophages or release of 24p3 upon neutrophil degranulation sequesters iron-laden siderophores to attenuate bacterial growth. Accordingly, 24p3-deficient mice are susceptible to bacterial pathogens whose siderophores would normally be chelated by 24p3. Specific granule deficiency (SGD) is a rare congenital disorder characterized by complete absence of proteins in secondary granules. Neutrophils from SGD patients, who are prone to bacterial infections, lack normal functions but the potential role of 24p3 in neutrophil dysfunction in SGD is not known. Here we show that neutrophils from 24p3-deficient mice are defective in many neutrophil functions. Specifically, neutrophils in 24p3-deficient mice do not extravasate to sites of infection and are defective for chemotaxis. A transcriptome analysis revealed that genes that control cytoskeletal reorganization are selectively suppressed in 24p3-deficient neutrophils. Additionally, small regulatory RNAs (miRNAs) that control upstream regulators of cytoskeletal proteins are also increased in 24p3-deficient neutrophils. Further, 24p3-deficient neutrophils failed to phagocytose bacteria, which may account for the enhanced sensitivity of 24p3-deficient mice to both intracellular (Listeria monocytogenes) and extracellular (Candida albicans, Staphylococcus aureus) pathogens. Interestingly, Listeria does not secrete siderophores and additionally, the siderophore secreted by Candida is not sequestered by 24p3. Therefore, the heightened sensitivity of 24p3-deficient mice to these pathogens is not due to sequestration of siderophores limiting iron availability, but is a consequence of impaired neutrophil function. Key words: Lipocalin, 24p3, neutrophils, cell motility, chemotaxis, MIRNA-362-3p To address the role of lipocalin 2 in unstimulated and fMLP-stimulated neutrophils derived from mouse bone marrow, we performed micorarray analysis of gene expression in unstimulated wild type (N=3), unstimulated lcn2 knockout (N=3), fMLP-stimulated wild type (N=2) and fMLP-stimulated lcn2 knockout (N=2) neutrophils. Upon stimulation, neutrophils were treated by fMLP at 10 micromolar for 20 minutes at 37 centigrade.
2013-01-31 | E-GEOD-43889 | biostudies-arrayexpress
Project description:Astrocytes provide physical and metabolic support for neurons, regulate the blood brain barrier, and react to injury, infection, and disease. When astrocytes become reactive, the regulation of the inflammatory state, the forms it takes, and its longevity are all poorly understood. Several models of acute inflammation have revealed astrocyte subpopulations that go beyond a two-activation state model, instead encompassing distinct functional subsets. However, how reactive astrocyte (RA) subsets evolve over time during chronic inflammatory disease or infection have been technically difficult to address. Here we use a prolific human pathogen, Toxoplasma gondii, that causes lifelong infection in the brain alongside a novel Lcn2CreERT2 reporter mouse line to examine astrocyte subsets during chronic inflammation. Single cell RNA sequencing revealed diverse astrocyte populations during chronic inflammation. Furthermore, we observed transcriptionally unique Lcn2CreERT2+ RAs, some of which changed over time in a manner suggestive of potential resolution and overall plasticity of RAs. In addition to an immune regulating Lcn2CreERT2+ astrocyte population enriched with gene transcripts encoding chemokines Ccl5, Cxcl9, Cxcl10 and receptors Ccr7 and Il7r, a specific set of Lcn2CreERT2+ astrocytes highly expressed transthyretin (Ttr), a secreted carrier protein involved in glycolytic enzyme activation and potential vasculature regulation and angiogenesis. These findings provide novel information about the evolution and diversity of reactive astrocyte subtypes and functional signatures at different stages of infection and an undocumented role for transthyretin expressing astrocytes in immune regulation at the central nervous system (CNS) vasculature.
2024-08-30 | GSE274474 | GEO
Project description:To investigate the mechansims that underly astrocyte dedifferentiation, we performed single cell RNA sequencing analysis of primary astrocytes after p53 loss and exposure to mitogens, EGF and and FGF. Primary astrocytes were isolated from postnatal day 3 inducible p53 knockout mice (GFAP-CreERT2;p53flox/flox;LSL-tdTomato), whereby treatment with 4-hydroxytamoxifen (4OHT) induces p53 loss and tdTomato labelling in GFAP+ astrocytes. Astrocytes were treated with 4OHT in media supplemented with EGF and FGF to induce recombination and astrocyte dedifferentiation in vitro.
2023-02-23 | GSE196408 | GEO