The gastrointestinal tract of mammals is inhabited by hundreds of distinct species of commensal microorganisms that exist in a mutualistic relationship with the host. The process by which the commensal microbiota influence the host immune system is poorly understood. We show here that colonization of the small intestine of mice with a single commensal microbe, segmented filamentous bacterium (SFB), is sufficient to induce the appearance of CD4+ T helper cells that produce IL-17 and IL-22 (Th17 cells) in the lamina propria. SFB adhere tightly to the surface of epithelial cells in the terminal ileum of mice with Th17 cells but are absent from mice that have few Th17 cells. Colonization with SFB was correlated with increased expression of genes associated with inflammation, anti-microbial defenses, and tissue repair, and resulted in enhanced resistance to the intestinal pathogen Citrobacter rodentium. Control of Th17 cell differentiation by SFB may thus establish a balance between optimal host defense preparedness and potentially damaging T cell responses. Manipulation of this commensal-regulated pathway may provide new opportunities for enhancing mucosal immunity and treating autoimmune disease.
Induction of intestinal Th17 cells by segmented filamentous bacteria.
Specimen part
View SamplesArx is a paired-box homeodomain transcription factor and the vertebrate ortholog to the Drosophila aristaless (al) gene. Mutations in Arx are associated with a variety of human diseases, including X-linked infantile spasm syndrome (OMIM: 308350), X-linked myoclonic epilepsy with mental retardation and spasticity (OMIM: 300432), X-linked lissencephaly with ambiguous genitalia (OMIM: 300215), X-linked mental retardation 54 (OMIM: 300419), and agenesis of the corpus callosum with abnormal genitalia (OMIM: 300004). Arx-deficient mice exhibit a complex, pleiotrophic phenotype, including decreased proliferation of neuroepithelial cells of the cortex, dysgenesis of the thalamus and olfactory bulbs, and abnormal nonradial migration of GABAergic interneurons. It has been suggested that deficits in interneuron specification, migration, or function lead to loss of inhibitory neurotransmission, which then fails to control excitatory activity and leads to epilepsy or spasticities. Given that Arx mutations are associated with developmental disorders in which epilepsy and spasticity predominate and that Arx-deficient mice exhibit deficits in interneuron migration, understanding the function of Arx in interneuron migration will prove crucial to understanding the pathology underlying interneuronopathies. Yet, downstream transcriptional targets of Arx, to date, remain unidentified.
Identification of Arx transcriptional targets in the developing basal forebrain.
No sample metadata fields
View SamplesTo acquire more information regarding the local immune events during the different phases of S. aureus infection, gene profiling using microarray technology was used to identify host genes whose expression is substantively altered in the kidneys during the acute (T2) and persistent phase of infection (T28). Genes associated with the distinct transcript profiles were identified by comparing the relative abundance of transcripts at 2 days (acute) and 28 days (persistent) of infection to their abundance in the kidneys of uninfected control animals (CTL).
The dynamics of T cells during persistent Staphylococcus aureus infection: from antigen-reactivity to in vivo anergy.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Microcephaly gene links trithorax and REST/NRSF to control neural stem cell proliferation and differentiation.
Time
View SamplesWe generated Ikk-KA/KA knock-in mice (KA/KA), in which an ATP binding site of Ikk Lys 44 was replaced by alanine. The knock-in mice develop severe skin lesions and begin to die after 6 to 10 months. We also found lung SCCs in some of the mice. To study lung SCC development, we stabilize the skin condition by crossing KA/KA with Lori.Ikk transgenic mice to generate KA/KA-Lori.Ikk mice, which 100% spontaneously developed lethal lung SCC at 4 to 6 months of age.
The pivotal role of IKKα in the development of spontaneous lung squamous cell carcinomas.
Age, Specimen part
View SamplesAtherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator.
ATF3 protects against atherosclerosis by suppressing 25-hydroxycholesterol-induced lipid body formation.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Mutant huntingtin's effects on striatal gene expression in mice recapitulate changes observed in human Huntington's disease brain and do not differ with mutant huntingtin length or wild-type huntingtin dosage.
No sample metadata fields
View SamplesTo test the hypotheses that mutant huntingtin protein length and wild-type huntingtin dosage have important effects on disease-related transcriptional dysfunction, we compared the changes in mRNA in seven genetic mouse models of Huntington's disease (HD) and postmortem human HD caudate. Transgenic models expressing short N-terminal fragments of mutant huntingtin (R6/1 and R6/2 mice) exhibited the most rapid effects on gene expression, consistent with previous studies. Although changes in the brains of knock-in and full-length transgenic models of HD took longer to appear, 15- and 22-month CHL2(Q150/Q150), 18-month Hdh(Q92/Q92) and 2-year-old YAC128 animals also exhibited significant HD-like mRNA signatures. Whereas it was expected that the expression of full-length huntingtin transprotein might result in unique gene expression changes compared with those caused by the expression of an N-terminal huntingtin fragment, no discernable differences between full-length and fragment models were detected. In addition, very high correlations between the signatures of mice expressing normal levels of wild-type huntingtin and mice in which the wild-type protein is absent suggest a limited effect of the wild-type protein to change basal gene expression or to influence the qualitative disease-related effect of mutant huntingtin. The combined analysis of mouse and human HD transcriptomes provides important temporal and mechanistic insights into the process by which mutant huntingtin kills striatal neurons. In addition, the discovery that several available lines of HD mice faithfully recapitulate the gene expression signature of the human disorder provides a novel aspect of validation with respect to their use in preclinical therapeutic trials.
Mutant huntingtin's effects on striatal gene expression in mice recapitulate changes observed in human Huntington's disease brain and do not differ with mutant huntingtin length or wild-type huntingtin dosage.
No sample metadata fields
View SamplesTo test the hypotheses that mutant huntingtin protein length and wild-type huntingtin dosage have important effects on disease-related transcriptional dysfunction, we compared the changes in mRNA in seven genetic mouse models of Huntington's disease (HD) and postmortem human HD caudate. Transgenic models expressing short N-terminal fragments of mutant huntingtin (R6/1 and R6/2 mice) exhibited the most rapid effects on gene expression, consistent with previous studies. Although changes in the brains of knock-in and full-length transgenic models of HD took longer to appear, 15- and 22-month CHL2(Q150/Q150), 18-month Hdh(Q92/Q92) and 2-year-old YAC128 animals also exhibited significant HD-like mRNA signatures. Whereas it was expected that the expression of full-length huntingtin transprotein might result in unique gene expression changes compared with those caused by the expression of an N-terminal huntingtin fragment, no discernable differences between full-length and fragment models were detected. In addition, very high correlations between the signatures of mice expressing normal levels of wild-type huntingtin and mice in which the wild-type protein is absent suggest a limited effect of the wild-type protein to change basal gene expression or to influence the qualitative disease-related effect of mutant huntingtin. The combined analysis of mouse and human HD transcriptomes provides important temporal and mechanistic insights into the process by which mutant huntingtin kills striatal neurons. In addition, the discovery that several available lines of HD mice faithfully recapitulate the gene expression signature of the human disorder provides a novel aspect of validation with respect to their use in preclinical therapeutic trials.
Mutant huntingtin's effects on striatal gene expression in mice recapitulate changes observed in human Huntington's disease brain and do not differ with mutant huntingtin length or wild-type huntingtin dosage.
No sample metadata fields
View SamplesAchieving a mechanistic understanding of disease and initiating preclinical therapeutic trials necessitate the study of huntingtin toxicity and its remedy in model systems. To allow the engagement of appropriate experimental paradigms, Huntingtons disease (HD) models need to be validated in terms of how they recapitulate a particular aspect of human disease. In order to examine transcriptome-related effects of mutant huntingtin, we compared striatal mRNA profiles from seven genetic mouse models of disease to that of postmortem human HD caudate using microarray analysis. Transgenic models expressing short N-terminal fragments of mutant huntingtin (R6/1 and R6/2 mice) exhibited the most rapid effects on gene expression, consistent with previous studies. Although changes in the brains of knock-in models of HD took longer to appear, 15-month and 22-month CHL2Q150/Q150, 18-month HdhQ92/Q92 and 2-year-old YAC128 animals also exhibited significant HD-like mRNA signatures. When the affected genes were compared across models, a robust concordance was observed. Importantly, changes concordant across multiple lines mice were also in excellent agreement with the mRNA changes seen in human HD caudate. Although it was expected that the expression of full-length huntingtin transprotein might result in unique gene expression changes compared to those caused by expression of an N-terminal huntingtin fragment, no discernable differences between full-length and fragment models were detected. There was, however, an overall concordance between transcriptomic signature and disease stage. We thus conclude that the transcriptional changes of HD can be modelled in several available lines of transgenic mice, comprising lines expressing both N-terminal and full-length mutant huntingtin proteins. The combined analysis of mouse and human HD transcriptomes provides an important chronology of mutant huntingtin's gene expression effects.
Mutant huntingtin's effects on striatal gene expression in mice recapitulate changes observed in human Huntington's disease brain and do not differ with mutant huntingtin length or wild-type huntingtin dosage.
Sex, Age, Specimen part
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