Project description:We compared genomic DNA methylation patterns and gene expression in African American children with persistent atopic asthma versus healthy controls. We identified 119 differentially methylated regions (DMRs) and 118 differentially methylated probes (DMPs) after adjustment for age, gender, race/ethnicity, batch effects, inflation, and multiple comparisons (false discovery rate-adjusted q<0.05). Genes differentially methylated include those with established roles in asthma and atopy, components of the extracellular matrix, genes related to immunity, cell adhesion, epigenetic regulation, and airway obstruction. Hypo- and hypermethylated genes were associated with increased and decreased gene expression respectively (P<2.8x10-6 for DMRs and P<7.8x10-10 for DMPs). Quantitative analysis of methylation-expression relationships in 53 differentially expressed genes demonstrated that 32 (60%) have significant (q<0.05) methylation-expression relationships within 5kb of the gene. 10 loci selected based on the relevance to asthma, magnitude of methylation change, and asthma specific methylation-expression relationships were validated in an independent cohort of children with asthma. case control design with nasal epithelial cells from 36 atopic asthmatic and 33 nonatopic nonasthmatic children from the inner city
Project description:Background: Nasal epithelia are emerging as a proxy measure of gene expression of the airway epithelium in asthma. We hypothesized that epigenetic marks regulate gene expression of the nasal epithelia and consequently may provide a novel target for allergic asthma. Methods: We compared genomic DNA methylation patterns and gene expression in African American children with persistent atopic asthma [N=36] versus healthy controls [N=36]. Results were validated in an independent population of asthmatics [N=30]. Results: We identified 186 genes with significant methylation changes, either as regions (differentially methylated regions [DMRs]) or single CpGs (differentially methylated probes [DMPs]) after adjustment for age, gender, race/ethnicity, batch effects, inflation, and multiple comparisons (false discovery rate-adjusted q<0.05). Genes differentially methylated include those with established roles in asthma and atopy, components of the extracellular matrix, genes related to immunity, cell adhesion, epigenetic regulation, and airway obstruction. The methylation changes are large (median 9.5%, range: 2.6-29.5% methylation change) and similar in magnitude to those observed in malignancies. Hypo- and hyper-methylated genes were associated with increased and decreased gene expression respectively (P<2.8x10-6 for DMRs and P<7.8x10-10 for DMPs). Quantitative analysis of methylation-expression relationships in 53 differentially expressed genes demonstrated that 32 (60%) have significant (q<0.05) methylation-expression relationships within 5kb of the gene. 10 loci selected based on the relevance to asthma, magnitude of methylation change, and asthma specific methylation-expression relationships were validated in an independent cohort of children with asthma. Conclusions: Our findings that epigenetic marks in respiratory epithelia are associated with allergic asthma in inner-city children provide new targets for biomarker development, and novel approaches to understanding disease pathogenesis. case control design with nasal epithelial cells from 36 atopic asthmatic and 36 nonatopic nonasthmatic children from the inner city
Project description:Background: Epigenetic marks, like asthma, are heritable. They are influenced by the environment, direct the maturation of T cellslymphocytes, and have been shown to enhance the development of allergic airways disease in mice. Thus, we hypothesized that epigenetic marks are associated with allergic asthma in inner-city children. Methods: We compared methylation patterns and gene expression in inner-city children with persistent atopic asthma versus healthy controls, using DNA and RNA from peripheral blood mononuclear cells (PBMCs) from inner city children aged 6-12 years with persistent atopic asthma children and healthy controls. Results were externally validated with the GABRIELA study population. Results: Comparing asthmatics (N=97) to controls (N=97), we identified 81 regions that were differentially methylated. Several immune genes were hypomethylated in asthmatics, including IL-13, RUNX3, and a number of specific genes relevant to natural killer cells (KIR2DL4, KIR2DL3, KIR3DL1, and KLRD1) and T cells lymphocytes (TIGIT). 14 differentially methylated regions (DMRs) were associated with the serum IgE concentration of IgE, including RUNX3. These results were internally and externally validated with a global methylation assessment using a different methodology in our inner-city cohort and an independent European cohort (GABRIELA). Hypo- and hypermethylated genes tended to be associated with increased and decreased gene expression, respectively (P<0.6x10-11 for asthma and ; P<0.01 for IgE). To further explore the relationship between methylation and gene expression, we created a matrix of genomic changes in methylation versus transcriptional changes (methyl eQTL) for asthma, and identified cis- and trans-regulated genes whose expression was related to asthma asthma-associated methylation marks. peripheral blood mononuclear cells (PBMCs) from 97 atopic asthmatic and 97 nonatopic nonasthmatic children
Project description:Analysis of gene expression changes in the von Hippel Lindau when mutant compared to wild-type at 4dpf using a whole genome microarray expression profiling. The von Hippel Lindau mutant displays a systemic hypoxic response under normoxic conditions. We performed single-colour microarrays to identify the gene expression changes which underpin the hypoxic phenotype. We used 3 biological replicates from both mutant and control, followed by analysis using Limma to identify significant gene expression changes. This work, together with ChIP-seq data for the Hif-1α in von Hippel Lindau mutants, should allow for the Hif-1α dependency of these gene expression changes to be assessed. The changes in gene expression between von Hippel Lindau mutants and wild-type controls was measured at 4 days post fertilisation. For both wild-type and mutant, 3 biological replicates, each of 30 embryos were used.
Project description:Using an oligonucleotide microarray we performed differential transcriptomic analysis of porcine kidneys subjected to intense ischemic stress which could be observed in donors deceased after circulatory death situation (60 min warm ischemia then 24h of cold storage in University of Wisconsin solution) compared to healthy kidneys (n=3). 43 genes were differentially expressed in ischemic versus healthy kidneys (adjusted p value <0.05 + log2 fold change >0.5 or <-0.5). Functional enrichment analysis via Gene ontology revealed relevant biological processes and signaling pathways such as: cellular responses to stress and cell cycle adaptation, metabolism modification, RNA reprograming, cellular phenotype changes and inflammation. Our data showed that ischemia is a dynamic process, with important transcriptional modifications on major pathways. We uncovered a number of targets which we will further validate as biomarkers and therapeutic targets to optimize organ quality. ISCHEMIA samples: Three independent porcine kidney (from different Large White pig) were clamped, removed and maintained clamped 60 min at 37°C, and then flushed with cold (4°C) University of Wisconsin preservation solution (UW) and stored at 4°C for 24h, then kidneys were immediatly sampled and frozen. CONTROL samples: Three independent porcine kidney (from different Large White pig) were removed and then immediatly sampled and frozen.