Purpose: The DBA/2J mouse is a model for secondary angle-closure glaucoma due to iris atrophy and pigment dispersion, which ultimately leads to increased intraocular pressure (IOP). We sought to correlate changes in retinal gene expression with glaucoma-like pathology by performing microarray analysis of retinal RNA from DBA/2J mice at 3 months before disease onset, and at 8 months, after IOP elevation. Methods: IOP was monitored monthly in DBA/2J animals by Tono-Pen and animals with normal (3 months) or elevated IOP (8 months) were identified. RNA was prepared from 3 individual retinas at each age, and the RNA was amplified and used to generate biotin-labeled probe for high density mouse Affymetrix arrays (U430.2). A subset of genes was selected for confirmation by quantitative RT-PCR using independent retina samples from DBA/2J animals at 3, 5 and 8 months of age, and compared to retinas from C57BL/6J control animals at 3 and 8 months. Results: There were changes in expression of 68 genes, with 32 genes increasing and 36 genes decreasing at 8 months versus 3 months. Upregulated genes were associated with immune response, glial activation, signaling and gene expression, while down-regulated genes included multiple crystallin genes. Significant changes in 9 upregulated genes and 2 downregulated genes were confirmed by quantitative RT-PCR, with some showing changes in expression by 5 months. Conclusions: DBA/2J retina shows evidence for glial activation and an immune-related response following IOP elevation, similar to what has been reported following acute elevation of IOP in other models.
Microarray analysis of retinal gene expression in the DBA/2J model of glaucoma.
Age
View SamplesOBJECTIVE: To determine whether macrophages, a type of cell implicated in the pathogenesis of ankylosing spondylitis (AS), exhibit a characteristic gene expression pattern. METHODS: Macrophages were derived from the peripheral blood of 8 AS patients (median disease duration 13 years [range <1-43 years]) and 9 healthy control subjects over 7 days with the use of granulocyte-macrophage colony-stimulating factor. Cells were stimulated for 24 hours with interferon-gamma (IFNgamma; 100 units/ml), were left untreated for 24 hours, or were treated for 3 hours with lipopolysaccharide (LPS; 10 ng/ml). RNA was isolated and examined by microarray and real-time quantitative reverse transcription-polymerase chain reaction analysis. RESULTS: Microarray analysis revealed 198 probe sets detecting the differential expression of 141 unique genes in untreated macrophages from AS patients compared with healthy controls. Clustering and principal components analysis clearly distinguished AS patients and controls. Of the differentially expressed genes, 78 (55%) were IFN-regulated, and their relative expression indicated a reverse IFN signature in AS patient macrophages, where IFNgamma-up-regulated genes were underexpressed and down-regulated genes were overexpressed. Treatment of macrophages with exogenous IFNgamma normalized the expression of these genes between patients and controls. In addition, the messenger RNA encoded by the IFNgamma gene was approximately 2-fold lower in AS patient macrophages at baseline (P = 0.004) and was poorly responsive to LPS (P = 0.018), as compared with healthy controls. CONCLUSIONS: Our findings reveal consistent differences in gene expression in macrophages from AS patients, with evidence of a striking reverse IFN signature. Together with poor expression and responsiveness of the IFNgamma gene, these results suggest that there may be a relative defect in IFNgamma gene regulation, with autocrine consequences and implications for disease pathogenesis.
Gene expression analysis of macrophages derived from ankylosing spondylitis patients reveals interferon-gamma dysregulation.
No sample metadata fields
View SamplesEpigenetic regulation serves as the basis for stem cell differentiation into distinct cell types, but it is unclear how global epigenetic changes are regulated during this process. Here, we tested the hypothesis that global chromatin organization affects the lineage potential of stem cells and that manipulation of chromatin dynamics influences stem cell function. Using nuclease sensitivity assays, we found a progressive decrease in chromatin digestion between pluripotent embryonic stem cells (ESCs), multipotent hematopoietic stem and progenitor cells (HSPCs), and mature hematopoietic cells. Quantification of chromatin composition by high-resolution microscopy revealed that ESCs contain significantly more euchromatin than HSPCs, with a further reduction in euchromatin as HSPCs transition into mature cells. Increased cellular maturation also led to heterochromatin localization to the nuclear periphery. Functionally, prevention of heterochromatin formation by inhibition of the histone methyltransferase G9a resulted in delayed hematopoietic stem cell (HSC) differentiation. Our results demonstrate significant global rearrangements of chromatin structure during embryonic and adult stem cell differentiation, and that heterochromatin formation by H3K9 methylation is an important regulator of HSC differentiation. Overall design: Examination of gene expression profile of in vitro cultured mouse HSC with the G9a inhibitor UNC0638
Progressive Chromatin Condensation and H3K9 Methylation Regulate the Differentiation of Embryonic and Hematopoietic Stem Cells.
Specimen part, Cell line, Treatment, Subject
View SamplesEstrogen-responsive genes were identified by transcript profiling of estrogen-treated MCF-7 breast cancer cells.
Identification of functional networks of estrogen- and c-Myc-responsive genes and their relationship to response to tamoxifen therapy in breast cancer.
No sample metadata fields
View SamplesRecent studies have suggested increased plasticity of differentiated cells within the intestine to act both as intestinal stem cells and tumour initiating cells. However, little is known of the processes that regulate this plasticity. Our previous work has shown that activating mutations of Kras or the NF-kB pathway can drive dedifferentiation of intestinal cells lacking Apc.
TGFβ pathway limits dedifferentiation following WNT and MAPK pathway activation to suppress intestinal tumourigenesis.
Specimen part
View SamplesRecent studies have suggested increased plasticity of differentiated cells within the intestine to act both as intestinal stem cells and tumour initiating cells. However, little is known of the processes that regulate this plasticity. Our previous work has shown that activating mutations of Kras or the NF-kB pathway can drive dedifferentiation of intestinal cells lacking Apc.
TGFβ pathway limits dedifferentiation following WNT and MAPK pathway activation to suppress intestinal tumourigenesis.
No sample metadata fields
View SamplesBy 2 weeks after stem cell transplantation, there was differentiated changes in T cell phenotype between autograft and allograft. RNA-seq was used to reveal the different transcription profiles of these T cells at week 2 after SCT. Overall design: Compare the transcription profile of the T cells in allograft and autograft transplantation patients.
Unique features and clinical importance of acute alloreactive immune responses.
Specimen part, Disease, Subject, Time
View SamplesSenescence can be transmitted in a paracrine way from cells undergoing Oncogene Induced Senescence (OIS) to nave normal cells. We define this phenomenon as paracrine senescence
A complex secretory program orchestrated by the inflammasome controls paracrine senescence.
Specimen part, Cell line
View SamplesSome neuropsychiatric disease, including schizophrenia, may originate during prenatal development, following periods of gestational hypoxia and placental oxidative stress. Here we investigated if gestational hypoxia promotes damaging secretions from the placenta that affect fetal development and whether a mitochondria-targeted antioxidant MitoQ might prevent this. Gestational hypoxia caused low birth-weight and changes in young adult offspring brain, mimicking those in human neuropsychiatric disease. Exposure of cultured neurons to fetal plasma or to secretions from the placenta or from model trophoblast barriers that had been exposed to altered oxygenation caused similar morphological changes. The secretions and plasma contained altered microRNAs whose targets were linked with changes in gene expression in the fetal brain and with human schizophrenia loci. Molecular and morphological changes in vivo and in vitro were prevented by a single dose of MitoQ bound to nanoparticles, which were shown to localise and prevent oxidative stress in the placenta but not in the fetus. We suggest the possibility of developing preventative treatments that target the placenta and not the fetus to reduce risk of psychiatric disease in later life. Overall design: 16 samples (4 biological replicates per group) were analysed using RNA sequencing. The 4 groups were: Normoxia+Saline (control sample), Normoxia+MitoQ-NP, Hypoxia+Saline and Hypoxia+MitoQ-NPs. Pair-wise comparison between all groups was performed.
Treating the placenta to prevent adverse effects of gestational hypoxia on fetal brain development.
No sample metadata fields
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