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Forney, C.

Publications and source records attributed to Forney, C..

10 recordsLinked to original sources

Single nucleus RNA sequencing of juvenile dermatomyositis skeletal muscle identifies altered angiogenic signaling

Juvenile dermatomyositis (JDM) is a chronic multisystem vasculopathy and inflammatory myopathy characterized by proximal muscle weakness, distinct rash, and risk of complications such as calcinosis cutis, skin ulceration, and mortality. Molecular insight from diagnostic muscle biopsy histology is limited, and the mechanistic pathoetiology of JDM remains poorly defined. We used single nuclei transcriptomics to assess muscle samples from patients with newly diagnosed treatment-naive JDM. As a control, we assessed muscle samples from patients with congenital (nemaline) myopathy (CM), a non-inflammatory disorder. A total of 25,794 high quality nuclei were analyzed and clustered into various muscle-resident or infiltrating cellular populations. JDM tissue was characterized by an enriched interferon (IFN) response signature across endothelial, stromal, and immune cell compartments. Endothelial and perivascular populations showed increased inflammatory and angiogenic programs. Intercellular communication inference analysis identified dysregulated vascular endothelial growth factor (VEGF)-related signaling involving endothelial, stromal, and myonuclear populations as a possible mechanism for myonuclear-driven modulation of the muscle microvasculature. Spatial RNA in situ hybridization supported increased expression of selected IFN responsive and angiogenesis signaling genes in JDM tissue. Collectively, these data provide a cell type-resolved view of treatment-naive JDM muscle and highlight vascular and IFN pathways for follow-up in larger cohorts.

genomics↗

A tonsil organoid model reveals Epstein-Barr virus infected germinal center B cell states during primary infection

Epstein-Barr virus (EBV) colonizes secondary lymphoid tissues to establish persistent infection and is strongly associated with malignancy and autoimmunity. Our understanding of EBV infection biology is hindered by a lack of models that capture infected B cell activity in the lymphoid tissue microenvironment. We therefore developed an EBV human tonsil organoid model to evaluate key B cell states and antiviral responses, including after primary infection. EBV promoted B cell differentiation into germinal center (GC)-like phenotypes and transcriptomic analyses highlighted numerous B cell transcriptional programs unique to EBV-infected cells. B cell receptor repertoire analysis revealed that most EBV-infected B cells underwent class switching but only rarely participated in somatic hypermutation. CD4 T cells, highly activated by organoid infection, limited EBV+ B cell outgrowth. Our findings demonstrate human tonsil organoids as a physiologically relevant model to investigate key aspects of EBV immunity and pathogenesis.

immunology↗

Global Evaluation of Congenital Heart Disease-Associated Non-Coding Variants

Abstract (Summary)Genome-wide association studies (GWAS) have mapped thousands of congenital heart disease (CHD)-associated variants within non-coding regions of the genome. Non-coding variants can alter regulatory mechanisms, such as transcription factor (TF) binding control of gene expression, potentially contributing human diseases. However, with the increasing number of disease-associated variants, comprehensive functional validation remains a significant challenge. In this work, we developed a novel method called SNP Bind-n-Seq to evaluate >3,000 CHD-risk variants for allelic binding for the cardiac TFs NKX2-5, GATA4, and TBX5 in a high-throughput manner. These binding affinity data sets were coupled with a massively parallel reporter assay (MPRA) to screen CHD-risk variant genotype-dependent regulatory activity. We identified 170 variants that exhibit allelic TF binding and 187 that modulate gene expression. Combining both approaches revealed three high-confidence variants with genotype-dependent TF binding, genotype-dependent transcriptional activity, and eQTL behavior in cardiac cells. Collectively, this study provides the first combined high-throughput biochemical and functional genomic evaluation of thousands of CHD-risk variants. HighlightsO_LIAllelic binding affinity measurements of [~]9,600 variants for NKX2-5, GATA4, and TBX5 C_LIO_LIEvaluaFon of >3,000 CHD-risk variants for genotype-dependent regulatory acFvity C_LIO_LIInteracFon networks idenFfy funcFonal variants and genes involving cardiac eQTLs C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=195 SRC="FIGDIR/small/691900v2_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@1f2dc96org.highwire.dtl.DTLVardef@1700929org.highwire.dtl.DTLVardef@696ec4org.highwire.dtl.DTLVardef@1e724d8_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

Systematic investigation of Epstein-Barr virus transcriptional regulator interactions with the human genome

We systematically investigate interactions between Epstein-Barr virus (EBV) transcriptional regulators (vTRs) and the human genome. Starting with 16 known and candidate vTRs, we identify nine whose introduction into human cells results in substantial alterations to host gene expression. Genome-scale determination of vTR genomic binding events and alterations to chromatin accessibility reveals a detailed map of EBVs functional interactions with the human genome, including >100,000 vTR binding events impacting almost a quarter of all human genes. BMRF1 emerges as a potent regulator, impacting >7,000 genes and altering >37,000 chromatin regions. Our results provide new evidence that EBV RTA interacts with and stabilizes the binding of human RBPJ. Network analysis reveals that many human genes are targeted by multiple EBV vTRs, highlighting the vast coordinated impact of EBV on human gene expression. This study provides a valuable, extensive resource for examining EBV-induced alterations to human gene regulation, with data available on multiple platforms.

genomics↗

Aryl Hydrocarbon Receptor Suppresses Eosinophilic Esophagitis Responses through OVOL1 and SPINK7

Eosinophilic esophagitis (EoE) is a type 2 allergic disease characterized by esophageal inflammation and epithelial cell dysfunction. Acquired loss of the anti-serine protease of kazal type 7 (SPINK7) in the squamous epithelium of the esophagus has a causal role in EoE pathogenesis. Yet there is a limited understanding of the factors that regulate its expression and responsiveness to inflammatory stimuli. Herein, we identified the transcription factor, ovo like transcriptional repressor 1 (OVOL1) as an esophageal selective gene product that regulates SPINK7 promoter activity. Overexpression of OVOL1 increased SPINK7 expression, whereas, its depletion decreased SPINK7 expression, impaired epithelial barrier and increased production of the pro-atopy cytokine thymic stromal lymphopoietin (TSLP). Mechanistically, ligands of AHR induced nuclear translocation of OVOL1 which in turn promoted epithelial cell differentiation, barrier function and SPINK7 expression. Interleukin (IL)-4 and IL-13 abolished AHR ligand-induced OVOL1 nuclear translocation. Stimulation with IL-13 abrogated the nuclear translocation of OVOL1 and promoted enhanced degradation of OVOL1 protein. This effect of IL-13 was dependent on the esophageal specific cysteine protease calpain-14. Translational studies demonstrated loss of OVOL1 protein expression in patients with EoE. In summary, AHR mediates its action via OVOL1-induced SPINK7 transcription, and IL-4 and IL-13 repress this pathway in EoE. As such, activation of the AHR pathway is a potential intervention strategy for reversing EoE. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/541192v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@1e946a1org.highwire.dtl.DTLVardef@1c087forg.highwire.dtl.DTLVardef@71ecc8org.highwire.dtl.DTLVardef@17044da_HPS_FORMAT_FIGEXP M_FIG C_FIG The influence of the exposome on regulatory networks in EoE pathogenesis. AHR is activated and influenced by diet nutrients, environmental toxicants, microbiome composition, tryptophan metabolites, and drugs. When AHR is activated, it promotes translocation of OVOL1 to the nucleus, which in turn promotes expression of epithelial genes including SPINK7. SPINK7 expression promotes epithelial differentiation, barrier function, decreased proteolytic activity, and decreased TSLP production. IL-4 and IL-13 inhibit OVOL1 nuclear translocation and therefore, repress SPINK7 expression. IL-13-stimulated CAPN14 expression decreases OVOL1 protein expression and SPINK7 transcription.

immunology↗

Macrophage epigenetic memories of early life injury drive neonatal nociceptive priming

The developing peripheral nervous and immune systems are functionally distinct from adults. These systems are vulnerable to early life injury, which influences outcomes related to nociception following subsequent injury later in life (i.e., "neonatal nociceptive priming"). The underpinnings of this phenomenon are largely unknown, although previous work indicates that macrophages are epigenetically trained by inflammation and injury. We found that macrophages are both necessary and partially sufficient to drive neonatal nociceptive priming possibly due to a long-lasting epigenetic remodeling. The p75 neurotrophic factor receptor (NTR) was an important effector in regulating neonatal nociceptive priming through modulation of the inflammatory profile of rodent and human macrophages. This "pain memory" was long lasting in females and could be transferred to a naive host to alter sex-specific pain-related behaviors. This study reveals a novel mechanism by which acute, neonatal post-surgical pain drives a peripheral immune-related predisposition to persistent pain following a subsequent injury. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=134 SRC="FIGDIR/small/528015v2_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@117ad6eorg.highwire.dtl.DTLVardef@17b4188org.highwire.dtl.DTLVardef@10b4d9borg.highwire.dtl.DTLVardef@1142094_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Epigenetic and Transcriptional Dysregulation in CD4+ T cells of Patients with Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin disorders in children. Disease etiology involves genetic and environmental factors, with the 29 independent AD risk loci enriched for risk allele-dependent gene expression in the skin and CD4+ T cell compartments. We investigated epigenetic mechanisms that may account for genetic susceptibility in CD4+ T cells. To understand gene regulatory activity differences in peripheral blood T cells in AD, we measured chromatin accessibility (ATAC-seq), NFKB1 binding (ChIP-seq), and gene expression (RNA-seq) in stimulated CD4+ T cells from subjects with active moderate-to-severe AD and age-matched, non-allergic controls. Open chromatin regions in stimulated CD4+ T cells were highly enriched for AD genetic risk variants, with almost half of AD risk loci overlapping with AD-dependent ATAC-seq peaks. AD-specific open chromatin regions were strongly enriched for NF{kappa}B DNA binding motifs. ChIP-seq identified hundreds of NFKB1-occupied genomic loci that were AD-specific or Control-specific. As expected, the AD-specific ChIP-seq peaks were strongly enriched for NF{kappa}B DNA binding motifs. Surprisingly, Control-specific NKFB1 ChIP-seq peaks were not enriched for NFKB1 motifs, instead containing motifs for other classes of human TFs, suggesting a mechanism involving altered indirect NFKB1 binding. Using DNA sequencing data, we identified 63 instances of genotype-dependent chromatin accessibility at 36 AD risk variants (30% of AD risk loci) that could lead to genotype-dependent expression at these loci. We propose that CD4+ T cells respond to stimulation in an AD-specific manner, resulting in disease and genotype-dependent chromatin accessibility involving NFKB binding. AUTHOR SUMMARYStimulated CD4+ T cells from patients with atopic dermatitis have disease-dependent regulation of how gene expression is regulated. This regulation is disease dependent and the way the DNA is accessible and the transcription factor NFKB1 binds is enriched for genetic risk variants. Clinically, the CD4+ T cells in the peripheral blood of patients with AD respond to stimulation in a disease and genotype-dependent manner.

genomics↗

Epstein-Barr virus nuclear antigen 2 (EBNA2) extensively rewires the human chromatin landscape at autoimmune risk loci

The interplay between environmental and genetic factors plays a key role in the development of many autoimmune diseases. In particular, the Epstein-Barr virus (EBV) is an established contributor to multiple sclerosis, lupus, and other disorders. Previously, we demonstrated that the EBV nuclear antigen 2 (EBNA2) transactivating protein occupies up to half of the risk loci for a set of seven autoimmune disorders. To further examine the mechanistic roles played by EBNA2 at these loci on a genome-wide scale, we globally examined gene expression, chromatin accessibility, chromatin looping, and EBNA2 binding, in a B cell line that was 1) uninfected, 2) infected with a strain of EBV lacking EBNA2, or 3) infected with a strain that expresses EBNA2. We identified >400 EBNA2-dependent differentially expressed human genes and >5,000 EBNA2 binding events in the human genome. ATAC-seq analysis revealed >2,000 regions in the human genome with EBNA2-dependent chromatin accessibility, and HiChIP-seq data revealed >1,700 regions where EBNA2 altered chromatin looping interactions. Importantly, autoimmune genetic risk loci were highly enriched at the sites of these EBNA2-dependent chromatin-altering events. We present examples of autoimmune risk genotype-dependent EBNA2 events, nominating genetic risk mechanisms for autoimmune risk loci such as ZMIZ1. Taken together, our results reveal important interactions between host genetic variation and EBNA2-driven disease mechanisms. Further, our study highlights a critical role for EBNA2 in rewiring human gene regulatory programs through rearrangement of the chromatin landscape and nominates these interactions as components of genetic mechanisms that influence the risk of multiple autoimmune diseases.

genomics↗

Genome-wide discovery of lupus genetic risk variant allelic regulatory activity

Genome-wide association studies of Systemic Lupus Erythematosus (SLE) nominate 3,073 genetic variants at 91 risk loci. To systematically screen these variants for allelic transcriptional enhancer activity, we constructed a massively parallel reporter assay (MPRA) library comprising 12,396 DNA oligonucleotides containing the genomic context around every allele of each SLE variant. Transfection into the Epstein-Barr virus-transformed B cell line GM12878 revealed 482 variants with enhancer activity, with 51 variants showing genotype-dependent (allelic) enhancer activity at 27 risk loci. Comparison of MPRA results in GM12878 and Jurkat T cell lines highlights shared and unique allelic transcriptional regulatory mechanisms at SLE risk loci. In-depth analysis of allelic transcription factor (TF) binding at and around allelic variants identifies one class of TFs whose DNA-binding motif tends to be directly altered by the risk variant and a second, larger class of TFs that bind allelically without direct alteration of their motif by the variant. Collectively, our approach provides a blueprint for the discovery of allelic gene regulation at risk loci for any disease and offers insight into the transcriptional regulatory mechanisms underlying SLE.

genomics↗

Genetic, inflammatory, and tissue-specific factors control expression of human calpain-14

Eosinophilic 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 mediated CAPN14 expression in differentiated esophageal epithelial cells following IL-13/STAT6 induction of CAPN14 promoter activity.

genomics↗