RESUMEN
Suicidal ideation (SI) often precedes and predicts suicide attempt and death, is the most common suicidal phenotype and is over-represented in veterans. The genetic architecture of SI in the absence of suicide attempt (SA) is unknown, yet believed to have distinct and overlapping risk with other suicidal behaviors. We performed the first GWAS of SI without SA in the Million Veteran Program (MVP), identifying 99,814 SI cases from electronic health records without a history of SA or suicide death (SD) and 512,567 controls without SI, SA or SD. GWAS was performed separately in the four largest ancestry groups, controlling for sex, age and genetic substructure. Ancestry-specific results were combined via meta-analysis to identify pan-ancestry loci. Four genome-wide significant (GWS) loci were identified in the pan-ancestry meta-analysis with loci on chromosomes 6 and 9 associated with suicide attempt in an independent sample. Pan-ancestry gene-based analysis identified GWS associations with DRD2, DCC, FBXL19, BCL7C, CTF1, ANNK1, and EXD3. Gene-set analysis implicated synaptic and startle response pathways (q's<0.05). European ancestry (EA) analysis identified GWS loci on chromosomes 6 and 9, as well as GWS gene associations in EXD3, DRD2, and DCC. No other ancestry-specific GWS results were identified, underscoring the need to increase representation of diverse individuals. The genetic correlation of SI and SA within MVP was high (rG = 0.87; p = 1.09e-50), as well as with post-traumatic stress disorder (PTSD; rG = 0.78; p = 1.98e-95) and major depressive disorder (MDD; rG = 0.78; p = 8.33e-83). Conditional analysis on PTSD and MDD attenuated most pan-ancestry and EA GWS signals for SI without SA to nominal significance, with the exception of EXD3 which remained GWS. Our novel findings support a polygenic and complex architecture for SI without SA which is largely shared with SA and overlaps with psychiatric conditions frequently comorbid with suicidal behaviors.
Asunto(s)
Trastorno Depresivo Mayor , Veteranos , Humanos , Ideación Suicida , Veteranos/psicología , Estudio de Asociación del Genoma Completo , Trastorno Depresivo Mayor/genética , Intento de Suicidio/psicología , Factores de RiesgoRESUMEN
Rare missense and nonsense variants in the Angiopoietin-like 7 (ANGPTL7) gene confer protection from primary open-angle glaucoma (POAG), though the functional mechanism remains uncharacterized. Interestingly, a larger variant effect size strongly correlates with in silico predictions of increased protein instability (r = -0.98), suggesting that protective variants lower ANGPTL7 protein levels. Here, we show that missense and nonsense variants cause aggregation of mutant ANGPTL7 protein in the endoplasmic reticulum (ER) and decreased levels of secreted protein in human trabecular meshwork (TM) cells; a lower secreted:intracellular protein ratio strongly correlates with variant effects on intraocular pressure (r = 0.81). Importantly, accumulation of mutant protein in the ER does not increase expression of ER stress proteins in TM cells (P > 0.05 for all variants tested). Cyclic mechanical stress, a glaucoma-relevant physiologic stressor, also significantly lowers ANGPTL7 expression in primary cultures of human Schlemm's canal (SC) cells (-2.4-fold-change, P = 0.01). Collectively, these data suggest that the protective effects of ANGPTL7 variants in POAG stem from lower levels of secreted protein, which may modulate responses to physiologic and pathologic ocular cell stressors. Downregulation of ANGPTL7 expression may therefore serve as a viable preventative and therapeutic strategy for this common, blinding disease.
Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Humanos , Glaucoma de Ángulo Abierto/patología , Glaucoma/metabolismo , Malla Trabecular/metabolismo , Presión Intraocular , Angiopoyetinas/genética , Angiopoyetinas/metabolismo , Proteínas Similares a la Angiopoyetina/genética , Proteínas Similares a la Angiopoyetina/metabolismo , Proteína 7 Similar a la Angiopoyetina/genéticaRESUMEN
Pseudoexfoliation glaucoma (PEXG) is characterized by dysregulated extracellular matrix (ECM) homeostasis that disrupts conventional outflow function and increases intraocular pressure (IOP). Prolonged IOP elevation results in optic nerve head damage and vision loss. Uniquely, PEXG is a form of open angle glaucoma that has variable penetrance, is difficult to treat and does not respond well to common IOP-lowering pharmaceuticals. Therefore, understanding modulators of disease severity will aid in targeted therapies for PEXG. Genome-wide association studies have identified polymorphisms in the long non-coding RNA lysyl oxidase-like 1-antisense 1 (LOXL1-AS1) as a risk factor for PEXG. Risk alleles, oxidative stress and mechanical stretch all alter LOXL1-AS1 expression. As a long non-coding RNA, LOXL1-AS1 binds hnRNPL and regulates global gene expression. In this study, we focus on the role of LOXL1-AS1 in the ocular cells (trabecular meshwork and Schlemm's canal) that regulate IOP. We show that selective knockdown of LOXL1-AS1 leads to cell-type-specific changes in gene expression, ECM homeostasis, signaling and morphology. These results implicate LOXL1-AS1 as a modulator of cellular homeostasis, altering cell contractility and ECM turnover, both of which are well-known contributors to PEXG. These findings support LOXL1-AS1 as a key target for modifying the disease.
Asunto(s)
Síndrome de Exfoliación , Glaucoma de Ángulo Abierto , ARN Largo no Codificante , Humanos , Glaucoma de Ángulo Abierto/genética , ARN Largo no Codificante/genética , Proteína-Lisina 6-Oxidasa/genética , Estudio de Asociación del Genoma Completo , Síndrome de Exfoliación/genética , Síndrome de Exfoliación/metabolismo , Aminoácido Oxidorreductasas/genéticaRESUMEN
INTRODUCTION: Cervical scrofulous lymphadenitis due to Mycobacterium avium complex (MAC) in immunocompetent adults is a rare disease. The presence of MAC infections demands meticulous clinical evaluation of patients along with detailed phenotypic and functional evaluation of their immune system including next-generation sequencing (NGS) analyses of target genes. METHODS: Exact clinical histories of the index patients both suffering from retromandibular/cervical scrofulous lymphadenitis were obtained along with phenotypic and functional immunological evaluations of leukocyte populations followed by targeted NGS-based sequencing of candidate genes. RESULTS: Immunological investigations showed normal serum immunoglobulin and complement levels, but lymphopenia, which was caused by significantly reduced CD3+CD4+CD45RO+ memory T-cell and CD19+ B-cell numbers. Despite normal T-cell proliferation to a number of accessory cell-dependent and -independent stimuli, the PBMC of both patients elaborated clearly reduced levels of a number of cytokines, including IFN-γ, IL-10, IL-12p70, IL-1α, IL-1ß, and TNF-α upon TCR-dependent T-cell stimulation with CD3-coated beads but also superantigens. The IFN-γ production deficiency was confirmed for CD3+CD4+ helper and CD4+CD8+ cytotoxic T cells on the single-cell level by multiparametric flow cytometry irrespective of whether PMA/ionomycin-stimulated whole blood cells or gradient-purified PBMC was analyzed. In the female patient L1, targeted NGS-based sequencing revealed a homozygous c.110T>C mutation in the interferon-γ receptor type 1 (IFNGR1) leading to significantly reduced receptor expression on both CD14+ monocytes and CD3+ T cells. Patient S2 presented with normal IFNGR1 expression on CD14+ monocytes but significantly reduced IFNGR1 expression on CD3+ T cells, despite the absence of detectable homozygous mutations in the IFNGR1 itself or disease-related target genes. Exogenous addition of increasing doses of IFN-γ resulted in proper upregulation of high-affinity FcγRI (CD64) on monocytes from patient S2, whereas monocytes from patient L1 showed only partial induction of CD64 expression after incubation with high doses of IFN-γ. CONCLUSION: A detailed phenotypic and functional immunological examination is urgently required to determine the cause of a clinically relevant immunodeficiency, despite detailed genetic analyses.
Asunto(s)
Linfadenitis , Infección por Mycobacterium avium-intracellulare , Adulto , Humanos , Femenino , Complejo Mycobacterium avium/genética , Complejo Mycobacterium avium/metabolismo , Leucocitos Mononucleares , Infección por Mycobacterium avium-intracellulare/genética , Infección por Mycobacterium avium-intracellulare/metabolismo , Citocinas/metabolismo , Linfadenitis/metabolismoRESUMEN
To identify pan-ancestry and ancestry-specific loci associated with attempting suicide among veterans, we conducted a genome-wide association study (GWAS) of suicide attempts within a large, multi-ancestry cohort of U.S. veterans enrolled in the Million Veterans Program (MVP). Cases were defined as veterans with a documented history of suicide attempts in the electronic health record (EHR; N = 14,089) and controls were defined as veterans with no documented history of suicidal thoughts or behaviors in the EHR (N = 395,064). GWAS was performed separately in each ancestry group, controlling for sex, age and genetic substructure. Pan-ancestry risk loci were identified through meta-analysis and included two genome-wide significant loci on chromosomes 20 (p = 3.64 × 10-9) and 1 (p = 3.69 × 10-8). A strong pan-ancestry signal at the Dopamine Receptor D2 locus (p = 1.77 × 10-7) was also identified and subsequently replicated in a large, independent international civilian cohort (p = 7.97 × 10-4). Additionally, ancestry-specific genome-wide significant loci were also detected in African-Americans, European-Americans, Asian-Americans, and Hispanic-Americans. Pathway analyses suggested over-representation of many biological pathways with high clinical significance, including oxytocin signaling, glutamatergic synapse, cortisol synthesis and secretion, dopaminergic synapse, and circadian rhythm. These findings confirm that the genetic architecture underlying suicide attempt risk is complex and includes both pan-ancestry and ancestry-specific risk loci. Moreover, pathway analyses suggested many commonly impacted biological pathways that could inform development of improved therapeutics for suicide prevention.
Asunto(s)
Estudio de Asociación del Genoma Completo , Veteranos , Negro o Afroamericano/genética , Sitios Genéticos , Predisposición Genética a la Enfermedad/genética , Humanos , Polimorfismo de Nucleótido Simple/genética , Intento de Suicidio , Población Blanca/genéticaRESUMEN
Since the discovery of immunoglobulin E (IgE) as a mediator of allergic diseases in 1967, our knowledge about the immunological mechanisms of IgE-mediated allergies has remarkably increased. In addition to understanding the immune response and clinical symptoms, allergy diagnosis and management depend strongly on the precise identification of the elicitors of the IgE-mediated allergic reaction. In the past four decades, innovations in bioscience and technology have facilitated the identification and production of well-defined, highly pure molecules for component-resolved diagnosis (CRD), allowing a personalized diagnosis and management of the allergic disease for individual patients. The first edition of the "EAACI Molecular Allergology User's Guide" (MAUG) in 2016 rapidly became a key reference for clinicians, scientists, and interested readers with a background in allergology, immunology, biology, and medicine. Nevertheless, the field of molecular allergology is moving fast, and after 6 years, a new EAACI Taskforce was established to provide an updated document. The Molecular Allergology User's Guide 2.0 summarizes state-of-the-art information on allergen molecules, their clinical relevance, and their application in diagnostic algorithms for clinical practice. It is designed for both, clinicians and scientists, guiding health care professionals through the overwhelming list of different allergen molecules available for testing. Further, it provides diagnostic algorithms on the clinical relevance of allergenic molecules and gives an overview of their biology, the basic mechanisms of test formats, and the application of tests to measure allergen exposure.
Asunto(s)
Hipersensibilidad , Humanos , Hipersensibilidad/diagnóstico , Hipersensibilidad/terapia , Alérgenos , Inmunoglobulina ERESUMEN
INTRODUCTION: Rapid urbanisation affects lifestyle and eating habits, predominantly causing a dietary shift that adds challenges to meet dietary recommendations within a complex food system. This research investigated dietary diversity and food choice drivers among low-income consumers in three urban settlements (Nairobi, Kenya; Bulawayo, Zimbabwe and Lilongwe, Malawi, representing rapid, moderate and slow urban growth patterns, respectively) as a first step towards improving diets across cultures and geographies. METHODS: Mixed methods data collection was employed for this study. Qualitative methods such as rapid foodscape appraisal workshops and food stories in selected low-income settlements in Nairobi, Bulawayo and Lilongwe were utilised to collect information on the food environments (food balances, infrastructure, safety, policies and institutions). Quantitative data such as socio-demographic characteristics and dietary diversity were collected via structured questionnaires using Cognitive Edge's SenseMaker® (n = 890, 450 and 440 for Nairobi, Bulawayo and Lilongwe, respectively). The dietary intake of respondents was assessed using a 24-h recall, which was then converted to the food group diversity score (FGDS). RESULTS: Different levels of compounded stress affected dietary diversity and quality, including high food prices, concerns about sanitation and hygiene and the role of food standards regulation bodies. The mean FGDS across all locations was lower than the recommended cut-off of 5 (4.5, 2.8 and 2.6 across Nairobi, Zimbabwe and Lilongwe, respectively). Additionally, in Nairobi, there were gender differences in diet diversity, with men having a higher dietary diversity score than women (4.6% vs. 4.3%; p = 0.004). The majority of respondents in Lilongwe (65%) reported price as the most important driver of food choice, compared to 38% in Nairobi and 42% in Bulawayo. DISCUSSION/CONCLUSIONS: Our observation of poor-quality diets provides further evidence of the need for food policies that are cognisant of the nutrition and health of the growing population of the urban poor. Such policies would focus on lowering the costs of nutritious foods as well as ensuring food safety within the complex food system observed in the urban low-income environment.
Asunto(s)
Dieta , Masculino , Humanos , Femenino , Kenia , Malaui , Zimbabwe , Encuestas y CuestionariosRESUMEN
The purpose of this work is to prove the suitability of integrated single-photon avalanche diode (SPAD)-based indirect time-of-flight (iTOF) for sub-100 µm precision depth sensing using a correlation approach with GHz modulation frequencies. For this purpose, a prototype containing a single pixel consisting of an integrated SPAD, quenching circuit, and two independent correlator circuits was fabricated in a 0.35 µm CMOS process and characterized. It achieved a precision of 70 µm and a nonlinearity of less than 200 µm at a received signal power of less than 100 pW. Sub-mm precision was achieved with a signal power of less than 200 fW. These results and the simplicity of our correlation approach underline the great potential of SPAD-based iTOF for future depth sensing applications.
RESUMEN
Individuals with pseudoexfoliation (PEX) syndrome exhibit various connective tissue pathologies associated with dysregulated extracellular matrix homeostasis. PEX glaucoma is a common, aggressive form of open-angle glaucoma resulting from the deposition of fibrillary material in the conventional outflow pathway. However, the molecular mechanisms that drive pathogenesis and genetic risk remain poorly understood. PEX glaucoma-associated single-nucleotide polymorphisms are located in and affect activity of the promoter of LOXL1-AS1, a long non-coding RNA (lncRNA). Nuclear and non-nuclear lncRNAs regulate a host of biological processes, and when dysregulated, contribute to disease. Here we report that LOXL1-AS1 localizes to the nucleus where it selectively binds to the mRNA processing protein, heterogeneous nuclear ribonucleoprotein-L (hnRNPL). Both components of this complex are critical for the regulation of global gene expression in ocular cells, making LOXL1-AS1 a prime target for investigation in PEX syndrome and glaucoma.
Asunto(s)
Síndrome de Exfoliación/genética , Glaucoma de Ángulo Abierto/genética , ARN Largo no Codificante/genética , Ribonucleoproteínas/genética , Aminoácido Oxidorreductasas/genética , Síndrome de Exfoliación/patología , Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad , Glaucoma de Ángulo Abierto/patología , Humanos , Complejos Multiproteicos/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genéticaRESUMEN
Identification of antibody-binding epitopes is crucial to understand immunological mechanisms. It is of particular interest for allergenic proteins with high cross-reactivity as observed in the lipid transfer protein (LTP) syndrome, which is characterized by severe allergic reactions. Art v 3, a pollen LTP from mugwort, is frequently involved in this cross-reactivity, but no antibody-binding epitopes have been determined so far. To reveal human IgE-binding regions of Art v 3, we produced three murine high-affinity mAbs, which showed 70-90% coverage of the allergenic epitopes from mugwort pollen-allergic patients. As reliable methods to determine structural epitopes with tightly interacting intact antibodies under native conditions are lacking, we developed a straightforward NMR approach termed hydrogen/deuterium exchange memory (HDXMEM). It relies on the slow exchange between the invisible antigen-mAb complex and the free 15N-labeled antigen whose 1H-15N correlations are detected. Due to a memory effect, changes of NH protection during antibody binding are measured. Differences in H/D exchange rates and analyses of mAb reactivity to homologous LTPs revealed three structural epitopes: two partially cross-reactive regions around α-helices 2 and 4 as well as a novel Art v 3-specific epitope at the C terminus. Protein variants with exchanged epitope residues confirmed the antibody-binding sites and revealed strongly reduced IgE reactivity. Using the novel HDXMEM for NMR epitope mapping allowed identification of the first structural epitopes of an allergenic pollen LTP. This knowledge enables improved cross-reactivity prediction for patients suffering from LTP allergy and facilitates design of therapeutics.
Asunto(s)
Alérgenos/inmunología , Proteínas Portadoras/inmunología , Reacciones Cruzadas , Epítopos/química , Inmunoglobulina E/inmunología , Espectroscopía de Resonancia Magnética/métodos , Antígenos de Plantas/inmunología , Deuterio/química , Hidrógeno/química , Polen/inmunología , Conformación ProteicaRESUMEN
Lysyl oxidase-like-1 (LOXL1), a vital crosslinking enzyme in elastin fiber maintenance, is essential for the stability and strength of elastic vessels and tissues. Variants in the LOXL1 locus associate with a dramatic increase in risk of exfoliation syndrome (XFS), a systemic fibrillopathy, which often presents with ocular hypertension and exfoliation glaucoma (XFG). We examined the role of LOXL1 in conventional outflow function, the prime regulator of intraocular pressure (IOP). Using Loxl1-/- , Loxl1+/- , and Loxl1+/+ mice, we observed an inverse relationship between LOXL1 expression and IOP, which worsened with age. Elevated IOP in Loxl1-/- mice was associated with a larger globe, decreased ocular compliance, increased outflow facility, extracellular matrix (ECM) abnormalities, and dilated intrascleral veins, yet, no dilation of arteries or capillaries. Interestingly, in living Loxl1-/- mouse eyes, Schlemm's canal (SC) was less susceptible to collapse when challenged with acute elevations in IOP, suggesting elevated episcleral venous pressure (EVP). Thus, LOXL1 expression is required for normal IOP control, while ablation results in altered ECM repair/homeostasis and conventional outflow physiology. Dilation of SC and distal veins, but not arteries, is consistent with key structural and functional roles for elastin in low-pressure vessels subjected to cyclical mechanical stress.
Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Animales , Síndrome de Exfoliación/metabolismo , Matriz Extracelular/metabolismo , Glaucoma/metabolismo , Homeostasis/fisiología , Presión Intraocular/fisiología , Ratones , Ratones Endogámicos C57BL , Hipertensión Ocular/metabolismoRESUMEN
BACKGROUND: This report describes the design and methodology of the "Eyes of Africa: The Genetics of Blindness," a collaborative study funded through the Human Heredity and Health in Africa (H3Africa) program of the National Institute of Health. METHODS: This is a case control study that is collecting a large well phenotyped data set among glaucoma patients and controls for a genome wide association study. (GWAS). Multiplex families segregating Mendelian forms of early-onset glaucoma will also be collected for exome sequencing. DISCUSSION: A total of 4500 cases/controls have been recruited into the study at the end of the 3rd funded year of the study. All these participants have been appropriately phenotyped and blood samples have been received from these participants. Recent GWAS of POAG in African individuals demonstrated genome-wide significant association with the APBB2 locus which is an association that is unique to individuals of African ancestry. This study will add to the existing knowledge and understanding of POAG in the African population.
Asunto(s)
Estudio de Asociación del Genoma Completo , Glaucoma de Ángulo Abierto , Proteínas Adaptadoras Transductoras de Señales , África/epidemiología , Ceguera/epidemiología , Ceguera/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , HumanosRESUMEN
Central corneal thickness (CCT) is one of the most heritable ocular traits and it is also a phenotypic risk factor for primary open angle glaucoma (POAG). The present study uses the BXD Recombinant Inbred (RI) strains to identify novel quantitative trait loci (QTLs) modulating CCT in the mouse with the potential of identifying a molecular link between CCT and risk of developing POAG. The BXD RI strain set was used to define mammalian genomic loci modulating CCT, with a total of 818 corneas measured from 61 BXD RI strains (between 60-100 days of age). The mice were anesthetized and the eyes were positioned in front of the lens of the Phoenix Micron IV Image-Guided OCT system or the Bioptigen OCT system. CCT data for each strain was averaged and used to QTLs modulating this phenotype using the bioinformatics tools on GeneNetwork (www.genenetwork.org). The candidate genes and genomic loci identified in the mouse were then directly compared with the summary data from a human POAG genome wide association study (NEIGHBORHOOD) to determine if any genomic elements modulating mouse CCT are also risk factors for POAG.This analysis revealed one significant QTL on Chr 13 and a suggestive QTL on Chr 7. The significant locus on Chr 13 (13 to 19 Mb) was examined further to define candidate genes modulating this eye phenotype. For the Chr 13 QTL in the mouse, only one gene in the region (Pou6f2) contained nonsynonymous SNPs. Of these five nonsynonymous SNPs in Pou6f2, two resulted in changes in the amino acid proline which could result in altered secondary structure affecting protein function. The 7 Mb region under the mouse Chr 13 peak distributes over 2 chromosomes in the human: Chr 1 and Chr 7. These genomic loci were examined in the NEIGHBORHOOD database to determine if they are potential risk factors for human glaucoma identified using meta-data from human GWAS. The top 50 hits all resided within one gene (POU6F2), with the highest significance level of p = 10-6 for SNP rs76319873. POU6F2 is found in retinal ganglion cells and in corneal limbal stem cells. To test the effect of POU6F2 on CCT we examined the corneas of a Pou6f2-null mice and the corneas were thinner than those of wild-type littermates. In addition, these POU6F2 RGCs die early in the DBA/2J model of glaucoma than most RGCs. Using a mouse genetic reference panel, we identified a transcription factor, Pou6f2, that modulates CCT in the mouse. POU6F2 is also found in a subset of retinal ganglion cells and these RGCs are sensitive to injury.
Asunto(s)
Córnea/anatomía & histología , Sitios Genéticos , Glaucoma/genética , Factores del Dominio POU/genética , Animales , Apoptosis/genética , Células Cultivadas , Mapeo Cromosómico , Córnea/patología , Paquimetría Corneal , Modelos Animales de Enfermedad , Embrión de Mamíferos , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Glaucoma/patología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Polimorfismo de Nucleótido Simple , Embarazo , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/fisiología , Factores de RiesgoRESUMEN
Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-ß signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified ß-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by ß-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm's canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17ß-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17ß-estradiol in AH supports a role for estrogen signaling in IOP regulation.
Asunto(s)
Estrógenos/genética , Presión Intraocular/genética , Transducción de Señal/genética , Animales , Humor Acuoso/fisiología , Bovinos , Línea Celular , Matriz Extracelular/genética , Glaucoma de Ángulo Abierto/genética , Humanos , Porcinos , Malla Trabecular/fisiologíaRESUMEN
Purpose: Schlemm's canal (SC) endothelial cells derived from donors with or without glaucoma showed different mechanical properties and gene expression. As an important contributor to the regulation of intraocular pressure (IOP) and pathogenesis of primary open-angle glaucoma (POAG), the heritable key epigenetic changes, methylation may play an important role in the physiologic function of SC cells. This study aims to identify differentially methylated CpG sites (DMSs) in primary cultures of human SC cells with or without glaucoma. Methods: We examined the methylation pattern of seven strains of primary human cells (two glaucoma and five normal SC cell samples), which were isolated and characterized using established protocols. DNA methylation was profiled using Illumina Human Methylation 450 BeadChip. Raw data were extracted and exported using Illumina GenomeStudio software. After quantile normalization, DNA methylation data were analyzed using R package RnBeads in Bioconductor. DMSs were filtered with p ≤ 1E-5, methylation change ≥ 0.1, and false discovery rate ≤ 0.05. The closest genes and the location of each CpG site were annotated using R package FDb.InfiniumMethylation.hg19. Gene Ontology and pathway analysis was performed using WebGestalt. Selected DMSs were validated using the Zymo qMethyl kit. Results: We used five non-glaucoma and two glaucomatous SC cell samples to profile genome-wide DNA methylation using Illumina Infinium Methylation BeadChips. Principle component analysis showed the separation between the glaucoma and control samples. After quality control and differential analysis, we identified 298 highly significant DMSs (p ≤ 1E-5). Among them, 221 DMSs were within 1 kb of a nearby gene. Gene Ontology analysis demonstrated significant enrichment in positive regulation of cell migration, negative regulation of endothelial cell proliferation, and stress fiber and actin filament bundles. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed enrichment in cell adhesion and gap junctions. Several glaucoma-related genes were identified, including TGFBR3, THBS1, PITX2, DAXX, TBX3, TNXB, ANGPT1, and PLEKHA7. We also examined differentially methylated regions (DMRs) near these CpG sites and identified significant DMRs in TBX3, TNXB1, DAXX, and PITX2. Conclusions: This study represents the first genome-wide DNA methylation profiling in cultured human primary SC cells. The DMSs were enriched in the pathways related to outflow resistance. Several DMRs were validated in glaucoma-associated genes, further suggesting the role of DNA methylation in glaucoma development. This study could provide comprehensive understanding of DNA methylation in glaucoma and its effect on aqueous humor outflow.
Asunto(s)
Proteínas Co-Represoras/genética , Células Endoteliales/metabolismo , Epigénesis Genética , Glaucoma de Ángulo Abierto/genética , Proteínas de Homeodominio/genética , Chaperonas Moleculares/genética , Proteínas de Dominio T Box/genética , Tenascina/genética , Factores de Transcripción/genética , Adulto , Anciano , Humor Acuoso/metabolismo , Estudios de Casos y Controles , Adhesión Celular , Proteínas Co-Represoras/metabolismo , Islas de CpG , Metilación de ADN , Células Endoteliales/patología , Femenino , Ontología de Genes , Glaucoma de Ángulo Abierto/metabolismo , Glaucoma de Ángulo Abierto/patología , Proteínas de Homeodominio/metabolismo , Humanos , Presión Intraocular , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patología , Masculino , Persona de Mediana Edad , Chaperonas Moleculares/metabolismo , Anotación de Secuencia Molecular , Cultivo Primario de Células , Proteínas de Dominio T Box/metabolismo , Tenascina/metabolismo , Factores de Transcripción/metabolismo , Proteína del Homeodomínio PITX2RESUMEN
BACKGROUND: Skin-based immunotherapy of type 1 allergies has recently been re-investigated as an alternative for subcutaneous injections. In the current study, we employed a mouse model of house dust mite (HDM)-induced lung inflammation to explore the potential of laser-facilitated epicutaneous allergen-specific treatment. METHODS: Mice were sensitized against native Dermatophagoides pteronyssinus extract and repeatedly treated by application of depigmented D pteronyssinus extract via laser-generated skin micropores or by subcutaneous injection with or without alum. Following aerosol challenges, lung function was determined by whole-body plethysmography and bronchoalveolar lavage fluid was analyzed for cellular composition and cytokine levels. HDM-specific IgG subclass antibodies were determined by ELISA. Serum as well as cell-bound IgE was measured by ELISA, rat basophil leukemia cell assay, and ex vivo using a basophil activation test, respectively. Cultured lymphocytes were analyzed for cytokine secretion profiles and cellular polarization by flow cytometry. RESULTS: Immunization of mice by subcutaneous injection or epicutaneous laser microporation induced comparable IgG antibody levels, but the latter preferentially induced regulatory T cells and in general downregulated T cell cytokine production. This effect was found to be a result of the laser treatment itself, independent from extract application. Epicutaneous treatment of sensitized animals led to induction of blocking IgG, and improvement of lung function, superior compared to the effects of subcutaneous therapy. During the whole therapy schedule, no local or systemic side effects occurred. CONCLUSION: Allergen-specific immunotherapy with depigmented HDM extract via laser-generated skin micropores offers a safe and effective treatment option for HDM-induced allergy and lung inflammation.
Asunto(s)
Alérgenos , Hipersensibilidad , Animales , Antígenos Dermatofagoides , Desensibilización Inmunológica , Hipersensibilidad/terapia , Rayos Láser , Ratones , PyroglyphidaeRESUMEN
Affecting nearly 80 million individuals, glaucoma is the number one cause of irreversible blindness in the world. This ocular disease describes a set of optic neuropathies of which primary open angle glaucoma (POAG) is the most common. POAG is associated with progressive visual field deterioration resulting from damage to the optic nerve and loss of retinal ganglion cells. Risk factors for POAG include elevated intraocular pressure, aging, African and Hispanic ancestry, and a positive family history of POAG. Multiple genes have been found to contribute to POAG. Much of POAG genetics and pathology has yet to be explained. Recent genome-wide association studies have identified a large number of novel loci associated with POAG and its endophenotypes. Genomic and proteomic profiling of biofluids has contributed to our knowledge of differential gene expression in POAG. Functional studies both in cell culture and animal models have confirmed the effects of variants and differential gene expression on ocular physiology while in silico analyses have increased our understanding of disease risk and progression so that we might better diagnose and treat this complex genetic illness.
Asunto(s)
Glaucoma de Ángulo Abierto/genética , Animales , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genómica , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular/fisiología , Proteómica , Trastornos de la Visión/fisiopatología , Campos Visuales/fisiologíaRESUMEN
This letter deals with neural networks as dynamical systems governed by finite difference equations. It shows that the introduction of k -many skip connections into network architectures, such as residual networks and additive dense networks, defines k th order dynamical equations on the layer-wise transformations. Closed-form solutions for the state-space representations of general k th order additive dense networks, where the concatenation operation is replaced by addition, as well as k th order smooth networks, are found. The developed provision endows deep neural networks with an algebraic structure. Furthermore, it is shown that imposing k th order smoothness on network architectures with d -many nodes per layer increases the state-space dimension by a multiple of k , and so the effective embedding dimension of the data manifold by the neural network is k·d -many dimensions. It follows that network architectures of these types reduce the number of parameters needed to maintain the same embedding dimension by a factor of k2 when compared to an equivalent first-order, residual network. Numerical simulations and experiments on CIFAR10, SVHN, and MNIST have been conducted to help understand the developed theory and efficacy of the proposed concepts.
Asunto(s)
Redes Neurales de la Computación , Simulación por ComputadorRESUMEN
Primary open angle glaucoma (POAG) is a complex disease and is one of the major leading causes of blindness worldwide. Genome-wide association studies have successfully identified several common variants associated with glaucoma; however, most of these variants only explain a small proportion of the genetic risk. Apart from the standard approach to identify main effects of variants across the genome, it is believed that gene-gene interactions can help elucidate part of the missing heritability by allowing for the test of interactions between genetic variants to mimic the complex nature of biology. To explain the etiology of glaucoma, we first performed a genome-wide association study (GWAS) on glaucoma case-control samples obtained from electronic medical records (EMR) to establish the utility of EMR data in detecting non-spurious and relevant associations; this analysis was aimed at confirming already known associations with glaucoma and validating the EMR derived glaucoma phenotype. Our findings from GWAS suggest consistent evidence of several known associations in POAG. We then performed an interaction analysis for variants found to be marginally associated with glaucoma (SNPs with main effect p-value <0.01) and observed interesting findings in the electronic MEdical Records and GEnomics Network (eMERGE) network dataset. Genes from the top epistatic interactions from eMERGE data (Likelihood Ratio Test i.e. LRT p-value <1e-05) were then tested for replication in the NEIGHBOR consortium dataset. To replicate our findings, we performed a gene-based SNP-SNP interaction analysis in NEIGHBOR and observed significant gene-gene interactions (p-value <0.001) among the top 17 gene-gene models identified in the discovery phase. Variants from gene-gene interaction analysis that we found to be associated with POAG explain 3.5% of additional genetic variance in eMERGE dataset above what is explained by the SNPs in genes that are replicated from previous GWAS studies (which was only 2.1% variance explained in eMERGE dataset); in the NEIGHBOR dataset, adding replicated SNPs from gene-gene interaction analysis explain 3.4% of total variance whereas GWAS SNPs alone explain only 2.8% of variance. Exploring gene-gene interactions may provide additional insights into many complex traits when explored in properly designed and powered association studies.
Asunto(s)
Epistasis Genética , Glaucoma de Ángulo Abierto/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , FenotipoRESUMEN
BACKGROUND: Recombinant fusion proteins of flagellin and antigens have been demonstrated to induce strong innate and adaptive immune responses. Such fusion proteins can enhance the efficacy of allergen-specific immunotherapy. OBJECTIVE: We sought to characterize different fusion proteins of flagellin and the major birch pollen allergen Bet v 1 for suitability as allergy vaccines. METHODS: A truncated version of flagellin (NtCFlg) was genetically fused to the N- or C-terminus of Bet v 1. Toll-like receptor (TLR) 5 binding was assessed with HEK293 cells expressing TLR5. Upregulation of CD40, CD80, CD83, and CD86 on monocyte-derived dendritic cells from allergic patients was analyzed by using flow cytometry. The T cell-stimulatory capacity of the fusion proteins was assessed with naive and Bet v 1-specific T cells. IgE binding was tested in inhibition ELISAs and basophil activation tests. Mice were immunized with the fusion proteins in the absence and presence of aluminum hydroxide. Cellular and antibody responses were monitored. Murine antibodies were tested for blocking capacity in basophil activation tests. RESULTS: Both fusion proteins matured monocyte-derived dendritic cells through TLR5. Compared with Bet v 1, the fusion proteins showed stronger T cell-stimulatory and reduced IgE-binding capacity and induced murine Bet v 1-specific antibodies in the absence of aluminum hydroxide. However, only antibodies induced by means of immunization with NtCFlg fused to the C-terminus of Bet v 1 inhibited binding of patients' IgE antibodies to Bet v 1. CONCLUSION: Bet v 1-flagellin fusion proteins show enhanced immunogenicity, reduced allergenicity, and intrinsic adjuvanticity and thus represent promising vaccines for birch pollen allergen-specific immunotherapy. However, the sequential order of allergen and adjuvant within a fusion protein determines its immunologic characteristics.