Pulmonary exposure to multiwalled carbon nanotubes (MWCNT) induces an inflammatory and rapid fibrotic response, although the long-term signaling mechanisms are unknown. The aim of this study was to examine the effects of 1, 10, 40, or 80 g MWCNT administered by pharyngeal aspiration on bronchoalveolar lavage (BAL) fluid for polymorphonuclear cell (PMN) infiltration, lactate dehydrogenase (LDH) activity, and lung histopathology for inflammatory and fibrotic responses in mouse lungs 1 mo, 6 mo, and 1 yr postexposure. Further, a 120-g crocidolite asbestos group was incorporated as a positive control for comparative purposes. Results showed that MWCNT increased BAL fluid LDH activity and PMN infiltration in a dose-dependent manner at all three postexposure times. Asbestos exposure elevated LDH activity at all 3 postexposure times and PMN infiltration at 1 mo and 6 mo postexposure. Pathological changes in the lung, the presence of MWCNT or asbestos, and fibrosis were noted at 40 and 80 g MWCNT and in asbestos-exposed mice at 1 yr postexposure. To determine potential signaling pathways involved with MWCNT-associated pathological changes in comparison to asbestos, up- and down-regulated gene expression was determined in lung tissue at 1 yr postexposure. Exposure to MWCNT tended to favor those pathways involved in immune responses, specifically T-cell responses, whereas exposure to asbestos tended to favor pathways involved in oxygen species production, electron transport, and cancer. Data indicate that MWCNT are biopersistent in the lung and induce inflammatory and fibrotic pathological alterations similar to those of crocidolite asbestos, but may reach these endpoints by different mechanisms.
Multiwalled carbon nanotube-induced pulmonary inflammatory and fibrotic responses and genomic changes following aspiration exposure in mice: A 1-year postexposure study.
Specimen part
View SamplesThe role of estrogen and testosterone in the regulation of gene expression in the proximal reproductive tract is not completely understood. To address this question, mice were treated with testosterone or estradiol and RNA from the efferent ducts and caput epididymis was processed and hybridized to Affymetrix MOE 430 2.0 microarrays. Analysis of array output identified probe sets in each tissue with altered levels in hormone treated versus control animals. Hormone treatment efficacy was confirmed by determination of serum hormone levels pre- and post-treatment and observed changes in transcript levels of previously reported hormone-responsive genes. Tissue-specific hormone sensitivity was observed with 2867 and 3197 probe sets changing significantly in the efferent ducts after estrogen and testosterone treatment, respectively. In the caput epididymis, 117 and 268 probe sets changed after estrogen and testosterone treatment, respectively, demonstrating a greater response to hormone in the efferent ducts than the caput epididymis. Transcripts sharing similar profiles in the intact and hormone-treated animals compared with castrated controls were also identified. Ontological analysis of probe sets revealed a significant number of hormone-regulated transcripts encode proteins associated with lipid metabolism, transcription and steroid metabolism in both tissues. Real-time RT-PCR was employed to confirm array data and investigate other potential hormone-responsive regulators of proximal reproductive tract function. The results of this work reveal previously unknown responses to estrogen in the caput epididymis and to testosterone in the efferent ducts as well as tissue specific hormone sensitivity in the proximal reproductive tract.
Regulation of gene expression by estrogen and testosterone in the proximal mouse reproductive tract.
Sex, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The AIM2-like Receptors Are Dispensable for the Interferon Response to Intracellular DNA.
Treatment, Time
View SamplesAnalysis of ALR-deficient cells indicates that ALRs are not required for the IFN response to intracellular DNA. To explore whether AIM2-like receptors activated another innate signaling pathway upon
The AIM2-like Receptors Are Dispensable for the Interferon Response to Intracellular DNA.
Treatment, Time
View SamplesReconstitution of cytomegalovirus (CMV)-specific immunity following transplant remains a primary clinical objective to prevent CMV disease, and adoptive immunotherapy of CMV-specific T cells can be an effective therapeutic approach. Due to the persistence of CMV, most CMV-specific CD8+ T cells become terminally differentiated effector cells (TEFF). However, a minor subset retains a memory phenotype (TM). Interestingly, recent studies suggest that CMV-specific CD8+ T cells with different phenotypes may have different abilities to reconstitute sustained immunity following transfer. The immunology of human CMV (HCMV) infections is reflected in the mouse model of MCMV infection. We found that HCMV- and MCMV-specific T cells displayed shared genetic programs, validating the MCMV model for studies of CMV-specific T cells in vivo. After transfer, the proliferative capacity of MCMV-specific TM cells was vastly superior to TEFF cells. Strikingly, TM cells expanded and established sustained and diverse T cell populations even after multiple challenges. Although both TEFF and TM cells could protect Rag-/- mice, only TM cells could consistently survive after transfer into immune replete, latently infected recipients and respond if recipient immunity was lost. These data show that CMV-specific TM cells retain memory function during persistent infection and can re-establish CMV immunity when necessary.
Memory T cells specific for murine cytomegalovirus re-emerge after multiple challenges and recapitulate immunity in various adoptive transfer scenarios.
Specimen part
View SamplesWe identified genes expressed in mouse skeletal muscle, during the process of muscle regeneration after injury, which are dysregulated in the absence of Mef2a expression. MEF2A is a member of the evolutionarily conserved MEF2 transcription factor family which has known roles in cardiac muscle development and function, but is not well studied in skeletal muscle. We performed a comparison of gene expression profiles in wild type and MEF2A knockout tibialis anterior muscle, seven days post-injury with cardiotoxin. The results indicated that a variety of genes expressed during muscle regeneration, predominantly microRNAs in the Gtl2-Dio3 locus, are dysregulated by the loss of MEF2A expression.
MEF2A regulates the Gtl2-Dio3 microRNA mega-cluster to modulate WNT signaling in skeletal muscle regeneration.
Specimen part
View SamplesHigher order chromosome structure and nuclear architecture can have profound effects on gene regulation. We analyzed how compartmentalizing the genome by tethering heterochromatic regions to the nuclear lamina affects dosage compensation in the nematode C. elegans. In this organism, the dosage compensation complex (DCC) binds both X chromosomes of hermaphrodites to repress transcription two-fold, thus balancing gene expression between XX hermaphrodites and XO males. X chromosome structure is disrupted by mutations in DCC subunits. Using X chromosome paint fluorescence microscopy, we found that X chromosome structure and subnuclear localization are also disrupted when the mechanisms that anchor heterochromatin to the nuclear lamina are defective. Strikingly, the heterochromatic left end of the X chromosome is less affected than the gene-rich middle region, which lacks heterochromatic anchors. These changes in X chromosome structure and subnuclear localization are accompanied by small, but significant levels of derepression of X-linked genes as measured by RNA-seq, without any observable defects in DCC localization and DCC-mediated changes in histone modifications. We propose a model in which heterochromatic tethers on the left arm of the X cooperate with the DCC to compact and peripherally relocate the X chromosomes, contributing to gene repression. Overall design: RNA-seq profiles of C. elegans L1 wild type hermaphrodites, cec-4, met-2 set-25, and DPY-27 RNAi. RNA-seq profiles or C. elegans. Strains are N2 Bristol strain (wild type), RB2301 cec-4(ok3124) IV, and EKM99 met-2(n4256) set-25(n5021) III. Biological replicates for each strain/stage listed separately.
Anchoring of Heterochromatin to the Nuclear Lamina Reinforces Dosage Compensation-Mediated Gene Repression.
Specimen part, Subject
View SamplesRegulation of neural stem cell (NSC) fate decisions is critical during the transition from a multicellular mammalian forebrain neuroepithelium to the multilayered neocortex. Forebrain development requires coordinated vascular investment alongside NSC differentiation. Vascular endothelial growth factor A (Vegf) has proven to be a pleiotrophic gene whose multiple protein isoforms regulate a broad range of effects in neurovascular systems. To test the hypothesis that the Vegf isoforms (120, 164, and 188) are required for normal forebrain development, we analyzed the forebrain transcriptome of mice expressing specific Vegf isoforms, Vegf120, VegfF188, or a combination of Vegf120/188. Transcriptome analysis identified differentially expressed genes in embryonic day (E) 9.5 forebrain, a time point preceding dramatic neuroepithelial expansion and vascular investment in the telencephalon. Meta-analysis identified gene pathways linked to chromosome-level modifications, cell fate regulation, and neurogenesis that were altered in Vegf isoform mice.
Shifts in the vascular endothelial growth factor isoforms result in transcriptome changes correlated with early neural stem cell proliferation and differentiation in mouse forebrain.
Specimen part
View SamplesNon-proteolytic ubiquitin signaling mediated by K63 ubiquitin chains plays a critical role in multiple pathways converging on NFKB activation that are key to the development and activation of immune cells. However, a complete understanding of how the regulation of ubiquitin signaling affects immune cells development and functionality is still missing. G Protein Suppressor 2 (GPS2) is a multi-functional protein that recently emerged as an important regulator of inflammation and lipid metabolism through inhibition of Ubc13 activity. Here, we have deleted GPS2 in the B cell lineage results and performed RNAseq of WT and KO splenic B cells. Overall design: RNA-seq of WT and_KO of GPS2 in Bcells.
Inhibition of Ubc13-mediated Ubiquitination by GPS2 Regulates Multiple Stages of B Cell Development.
Specimen part, Subject
View SamplesCompared differentially express genes by sex in mouse for the following tissues: hypothalamus, liver, kidney, ovaries and testis (3 biological x 2 technical replicates for each tissues/sex). We used Affymetrix MOE430A Genechip arrays.
Major molecular differences between mammalian sexes are involved in drug metabolism and renal function.
Sex, Specimen part
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