43 research outputs found
A functional mechanism for a non-coding variant near AGTR2 associated with risk for preterm birth
No full textpublishedVersio
Epigenetic and Transcriptional Dysregulation in T cells of Patients with Atopic Dermatitis
No full textRationale: Atopic dermatitis (AD) is linked to genetic and environmental risk factors. The effect of these factors on molecular and transcriptional events is not well understood. Immunologically, AD involves skin barrier defects and CD4+ T cells that produce inflammatory cytokines and amplify epidermal dysfunction Our objective was to investigate epigenetic mechanisms that may account for genetic susceptibility in CD4+ T cells.
Methods: We measured chromatin accessibility (ATAC-seq), NFKB1 binding (ChIP-seq), and gene expression (RNA-seq) in anti-CD3/CD28 stimulated CD4+ T cells from 6 subjects with active moderate-to-severe AD and 6 age-matched non-allergic controls.
Results: AD genetic risk loci were enriched for open chromatin regions in stimulated CD4+ T cells. The majority of ATAC-seq peaks were shared between matched AD-control pairs, consistent with those sections of chromatin being equally available. In contrast, NFKB DNA binding motifs were enriched in AD-dependent open chromatin. NFKB1 ChIP-seq identified genomic regions that were more strongly bound in AD cases, more strongly bound in controls, or shared between cases and controls. Chromatin that was strongly accessible and bound by NFKB1 in AD was enriched for AD genetic risk variants. Using whole genome sequencing data, we identified genotype-dependent accessible chromatin at AD risk loci corresponding to 32 genes with genotype-dependent expression in stimulated CD4+ T cells.
Conclusions: The response of CD4+ T cells to stimulation is AD-specific and results in differential chromatin accessibility and transcription factor binding. These differences in transcriptional regulation result in epigenetic and transcriptional dysregulation in CD4+ T cells of patients with AD
Transcription factors operate across disease loci, with EBNA2 implicated in autoimmunity
No full textAdditional file 3 of A functional mechanism for a non-coding variant near AGTR2 associated with risk for preterm birth
No full textAdditional file 3: Fig. S1. EMSA confirms allele-dependent binding of HOXA10 at rs7889204. Fig. S2. EMSA does not confirm allele-dependent binding of FOXA1 at rs7889204
Additional file 2 of A functional mechanism for a non-coding variant near AGTR2 associated with risk for preterm birth
No full textAdditional file 2. Human AGTR2 expression analysis
Genetic, Inflammatory, and Epithelial Cell Differentiation Factors Control Expression of Human Calpain-14
No full textEosinophilic esophagitis (EoE) is a chronic, food-driven allergic disease resulting in eosinophilic esophageal inflammation. We recently found that EoE susceptibility is associated with genetic variants in the promoter of CAPN14, a gene with reported esophagus-specific expression. CAPN14 is dynamically up-regulated as a function of EoE disease activity and after exposure of epithelial cells to interleukin-13 (IL-13). Herein, we aimed to explore molecular modulation of CAPN14 expression. We identified three putative binding sites for the IL-13-activated transcription factor STAT6 in the promoter and first intron of CAPN14. Luciferase reporter assays revealed that the two most distal STAT6 elements were required for the ∼10-fold increase in promoter activity subsequent to stimulation with IL-13 or IL-4, and also for the genotype-dependent reduction in IL-13-induced promoter activity. One of the STAT6 elements in the promoter was necessary for IL-13-mediated induction of CAPN14 promoter activity while the other STAT6 promoter element was necessary for full induction. Chromatin immunoprecipitation in IL-13 stimulated esophageal epithelial cells was used to further support STAT6 binding to the promoter of CAPN14 at these STAT6 binding sites. The highest CAPN14 and calpain-14 expression occurred with IL-13 or IL-4 stimulation of esophageal epithelial cells under culture conditions that allow the cells to differentiate into a stratified epithelium. This work corroborates a candidate molecular mechanism for EoE disease etiology in which the risk variant at 2p23 dampens CAPN14 expression in differentiated esophageal epithelial cells following IL-13/STAT6 induction of CAPN14 promoter activity
The antiprotease SPINK7 serves as an inhibitory checkpoint for esophageal epithelial inflammatory responses
No full textLoss of esophageal SPINK7 unleashes protease activity, impairs barrier function, and induces proinflammatory responses.</jats:p
The Anti-protease SPINK7 is a Checkpoint Regulator of Esophageal Epithelial Inflammatory Responses
No full textAdditional file 1 of A functional mechanism for a non-coding variant near AGTR2 associated with risk for preterm birth
No full textAdditional file 1. Prioritization of functional SNPs and predication of allele-dependent TF bindin
Filaggrin loss-of-function variants are associated with atopic dermatitis phenotypes in a diverse, early-life prospective cohort
No full textLoss-of-function (LoF) variants in the filaggrin (FLG) gene are the strongest known genetic risk factor for atopic dermatitis (AD), but the impact of these variants on AD outcomes is poorly understood. We comprehensively identified genetic variants through targeted region sequencing of FLG in children participating in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort. Twenty FLG LoF variants were identified, including 1 novel variant and 9 variants not previously associated with AD. FLG LoF variants were found in the cohort. Among these children, the presence of 1 or more FLG LoF variants was associated with moderate/severe AD compared with those with mild AD. Children with FLG LoF variants had a higher SCORing for Atopic Dermatitis (SCORAD) and higher likelihood of food allergy within the first 2.5 years of life. LoF variants were associated with higher transepidermal water loss (TEWL) in both lesional and nonlesional skin. Collectively, our study identifies established and potentially novel AD-associated FLG LoF variants and associates FLG LoF variants with higher TEWL in lesional and nonlesional skin
