Filters
Technology
Platform
GSE18348
Mus musculus
14 Downloadable Samples
Description
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.
Publication Title
Induction of intestinal Th17 cells by segmented filamentous bacteria.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 65 Downloadable Samples
Description
It is widely believed that the carcinogenic action of ionizing radiation is due to targeted DNA damage and resulting mutations, but there is also substantial evidence that non-targeted radiation effects alter epithelial phenotype and the stromal microenvironment. Activation of transforming growth factor 1 (TGF) is a non-targeted radiation effect that mediates cell fate decisions following DNA damage and regulates microenvironment composition; it could either suppress or promote cancer. We asked if such non-targeted radiation effects contribute to carcinogenesis by using a novel radiation chimera model. Unirradiated Trp53 null mammary epithelium was transplanted to the mammary stroma, previously divested of endogenous epithelia, of mice previously exposed to a single low (10 -100 cGy) radiation dose. By 300 days, 100% of transplants in irradiated hosts at either 10 or 100 cGy had developed Trp53 null breast carcinomas compared to 54% in unirradiated hosts. Tumor growth rate was also increased by high, but not low, dose host irradiation. In contrast, irradiation of Tgfb1 heterozygote mice prior to transplantation failed to decrease tumor latency, or increase growth rate at any dose. Host irradiation significantly reduced the latency of invasive ductal carcinoma compared to spindle cell carcinoma. However, irradiation of either host genotype significantly increased the frequency of estrogen receptor negative tumors. These data demonstrate two concepts critical to understanding radiation risks. First, non-targeted radiation effects can significantly promote the frequency and alter the features of epithelial cancer. Second, radiation-induced TGF activity is a key mechanism of tumor promotion.
Publication Title
Radiation acts on the microenvironment to affect breast carcinogenesis by distinct mechanisms that decrease cancer latency and affect tumor type.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 14 Downloadable Samples
Description
Recurrent somatic mutations in TET2 and in other genes that regulate the epigenetic state have been identified in patients with myeloid malignancies and in other cancers. However, the in vivo effects of Tet2 loss have not been delineated. We report here that Tet2 loss leads to increased stem-cell self-renewal and to progressive stem cell expansion. Consistent with human mutational data, Tet2 loss leads to myeloproliferation in vivo, notable for splenomegaly and monocytic proliferation. In addition, haploinsufficiency for Tet2 confers increased self-renewal and myeloproliferation, suggesting that the monoallelic TET2 mutations found in most TET2-mutant leukemia patients contribute to myeloid transformation. This work demonstrates that absent or reduced Tet2 function leads to enhanced stem cell function in vivo and to myeloid transformation.
Publication Title
Tet2 loss leads to increased hematopoietic stem cell self-renewal and myeloid transformation.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 11 Downloadable Samples
Description
Early life exposure to antibiotics alters the gut microbiome. These alterations lead to changes in metabolic homeostasis and an increase in host adiposity. We used microarrays to identify metabolic genes that may be up- or down-regulated secondary to antibiotic exposure.
Publication Title
No associated publication
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
Description
This is a comparative microarray analysis of 36-65 hybridomas switching at normal low frequencies in vitro vs. selected variants spontaneously switching at 100 fold higher frequencies in vitro.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 47 Downloadable Samples
Description
Nutritional and genetic risk factors for intestinal tumors are additive on mouse tumor phenotypes, demonstrating that diet and genetic factors impact risk by distinct combinatorial mechanisms. We analyzed expression profiles of small intestine crypts and villi from mice with nutritional and genetic risk factors. The results advanced our understanding of the mechanistic roles played by major risk factors in the pathogenesis of intestinal tumors.
Publication Title
Paneth cell marker expression in intestinal villi and colon crypts characterizes dietary induced risk for mouse sporadic intestinal cancer.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 9 Downloadable Samples
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part, Time
View Samples- Mus musculus
- 9 Downloadable Samples
Description
The morphogen Indian Hedgehog plays a very important role during intestinal embryogenesis, but also maintains homeostasis in the adult gut. Intestinal Hedgehog is expressed by the intestinal epithelium and signals in paracrine manner to fibroblasts in the stromal compartment. We studied the colonic changes upon activation of the Hedgehog pathway by deleting the Hedgehog receptor Patched1 in order to alleviate its repressive function.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part, Time
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Waldenstom macroglobulinemia (WM) with 6q del is still unknown. In the present study, we analyzed gene expression signiture of WM with 6q del.
Publication Title
Gene Expression Profile Signature of Aggressive Waldenström Macroglobulinemia with Chromosome 6q Deletion.
Sample Metadata Fields
Specimen part, Disease
View Samples- Mus musculus
- 5 Downloadable Samples
Description
Following neural tube closure at around E9.5, the rhombic lip within the rhombomere 1/isthmus region ("upper rhombic lip") produces a sequence of neuronal lineages that populate the brainstem and cerebellum. The transcription factor Atoh1 (Math1) is required for this specialized neurogenesis, although the genetic programs that delineate the temporal cell fate changes downstream of Atoh1 are not well characterized. We examined the gene expresion changes that take place within Atoh1 lineages
Publication Title
Genes expressed in Atoh1 neuronal lineages arising from the r1/isthmus rhombic lip.
Sample Metadata Fields
Specimen part
View Samples