The molecular mechanism underlying cardiac remodeling following myocardial infarction have been incompletely understood. Until now, most studies have been performed in rodents. We studied cardiac remodeling in the physiologically more relevant animal model, the swine.
Left ventricular remodeling in swine after myocardial infarction: a transcriptional genomics approach.
Sex
View SamplesThe mucosa that lines the respiratory and gastrointestinal (GI) tracts is an important portal of entry for pathogens and provides the frontline of immune defense against HIV infection. Using the simian immunodeficiency virus (SIV) rhesus macaque model, we have performed a comparative analysis of host gene expression in the lung and GI mucosa in response to SIV infection and antiretroviral therapy.
Enhanced innate antiviral gene expression, IFN-α, and cytolytic responses are predictive of mucosal immune recovery during simian immunodeficiency virus infection.
Specimen part
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis. This particular series represents all data from d 10. The additional expression data from the time course (d8-d20) is represented by series GSE2259 ("Testicular gene expression in SCARKO mice during prepuberty").
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis.
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesMicroarray anlaysis was performed to investigate gene expression patterns of other transcription factors involved in early retinal and/or forebrain development using human embryonic stem cell-derived retinal and forebrain progenitor cells. After 20 days of differentiation, vesicular neurospheres selectively expressed multiple retinal transcription factor genes appropriate for the OV stage of retinogenesis, whereas nonvesicular neurospheres expressed transcription factors indicative of the embryonic forebrain. Many transcription factor genes associated with retinal development were present at higher levels in vesicular vs. nonvesicular neurospheres. Nonvesicular neurospheres, on the other hand, expressed higher levels of transcription factors implicated in early forebrain development. Taken together, results indicated that the vesicular and nonvesicular neurospheres harbored retinal progenitor cells and early forebrain populations, respectively.
Optic vesicle-like structures derived from human pluripotent stem cells facilitate a customized approach to retinal disease treatment.
Specimen part
View SamplesSalmonella enterica serotype Typhimurium cause a localized enteric infection in immunocompetent patients while human immunodeficiency virus (HIV)-infected patients develop a life threatening bacteremia. We used a rhesus macaque ileal loop model to study how simian immunodeficiency virus (SIV) infection triggers defects in mucosal barrier function that enhance S. Typhimurium dissemination. SIV infection resulted in significant depletion of CD4+ T cells in the intestinal mucosa. Gene expression profiling revealed a defective TH17 response (with suppression of IL-17 and IL-22 expression) and impaired homeostasis of the intestinal epithelium in SIV-infected animals during NTS infection. These findings correlated with an impaired ability of lamina propria CD4+ T cells from SIV-infected macaques to produce IL-17 upon ex vivo stimulation, while production of IFN-gamma was not affected. This cytokine imbalance in SIV-infected animals was associated with reduced expression of genes required for intestinal epithelial maintenance and repair, increased fluid secretion during NTS infection, epithelial damage and translocation of a non-invasive S. Typhimurium mutant. Although no defects in neutrophil recruitment were noted, the ileum of SIV-infected animals contained lower levels of the enzyme myeloperoxidase, which may indicate defects in neutrophil killing capacity. S. Typhimurium was recovered in markedly increased numbers from the mesenteric lymph nodes of SIV-infected macaques, illustrating the increased potential for systemic dissemination during co-infection. Our data suggest that SIV-infection causes a multi-factorial defect in mucosal barrier function that promotes bacterial dissemination.
Simian immunodeficiency virus-induced mucosal interleukin-17 deficiency promotes Salmonella dissemination from the gut.
No sample metadata fields
View SamplesDespite intense investigation of intrinsic and extrinsic factors that regulate pluripotency, the process of initial fate commitment of embryonic stem (ES) cells is still poorly understood. Here, we used a genome wide shRNA screen in mouse ES cells to identify genes that are essential for initiation of differentiation. Knockdown of the scaffolding protein Mek binding protein 1 (Mp1, also known as Lamtor3, Map2k1ip1) stimulated self-renewal of ES cells, blocked differentiation and promoted proliferation. Fibroblast growth factor 4 (FGF4) signaling is required for initial fate commitment of ES cells. Knockdown of Mp1 inhibited FGF4-induced differentiation but did not alter FGF4 driven proliferation. This uncoupling of differentiation and proliferation was also observed when oncogenic Ras isoforms were over expressed in ES cells. Knockdown of Mp1 redirected FGF4 signaling from differentiation towards pluripotency and upregulated the pluripotency-related genes Esrrb, Rex1, Tcl1 and Sox2.
A genome-wide RNAi screen in mouse embryonic stem cells identifies Mp1 as a key mediator of differentiation.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesWe performed genomic and transcriptomic analysis of seven cases of molecular Burkitt lymphoma (mBL) developed in immunosuppressed patients who underwent solid organ transplantation. Interestingly, three cases (43%) were MYC-translocation-negative and revealed the 11q-gain/loss aberration recently identified in 3% of mBL developed in immunocompetent hosts.1 Based on array CGH data, minimal gain and loss regions of 11q (MGR/~4Mb and MLR/~13.5Mb, respectively) were defined and integrative genomic and transcriptomic analysis identified 35 differentially expressed genes, when compared with classic BL. All 16 MGR-dysregulated genes were upregulated, including cancer related USP2, CBL and PAFAH1B2. As expected, all 19 MGL-dysregulated genes were downregulated and two of them, TBRG1 and EI24, are potential tumor suppressor genes. Interestingly, the vast majority of dysregulated 11q23-q25 genes are involved in the MYC and TP53 networks. We hypothesize that the 11q-gain/loss aberration represents a molecular variant of t(8q24/MYC) and affects the same pathological pathways as the MYC oncogene.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesLong non-coding RNAs show highly tissue and disease specific expression profiles. We analyzed prostate cancer and normal adjacent prostate samples to identify cancer-specific transcripts and found 334 candidates, of which 15 were validated by RT-PCR.
Novel long non-coding RNAs are specific diagnostic and prognostic markers for prostate cancer.
No sample metadata fields
View Samples