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1.
Genome Res ; 31(6): 1069-1081, 2021 06.
Article in English | MEDLINE | ID: mdl-34011578

ABSTRACT

Single-cell RNA sequencing (scRNA-seq) is a widely used method for identifying cell types and trajectories in biologically heterogeneous samples, but it is limited in its detection and quantification of lowly expressed genes. This results in missing important biological signals, such as the expression of key transcription factors (TFs) driving cellular differentiation. We show that targeted sequencing of ∼1000 TFs (scCapture-seq) in iPSC-derived neuronal cultures greatly improves the biological information garnered from scRNA-seq. Increased TF resolution enhanced cell type identification, developmental trajectories, and gene regulatory networks. This allowed us to resolve differences among neuronal populations, which were generated in two different laboratories using the same differentiation protocol. ScCapture-seq improved TF-gene regulatory network inference and thus identified divergent patterns of neurogenesis into either excitatory cortical neurons or inhibitory interneurons. Furthermore, scCapture-seq revealed a role for of retinoic acid signaling in the developmental divergence between these different neuronal populations. Our results show that TF targeting improves the characterization of human cellular models and allows identification of the essential differences between cellular populations, which would otherwise be missed in traditional scRNA-seq. scCapture-seq TF targeting represents a cost-effective enhancement of scRNA-seq, which could be broadly applied to improve scRNA-seq resolution.


Subject(s)
Induced Pluripotent Stem Cells , Single-Cell Analysis , Gene Expression Profiling/methods , Gene Regulatory Networks , Humans , Induced Pluripotent Stem Cells/metabolism , Sequence Analysis, RNA/methods , Single-Cell Analysis/methods , Transcription Factors/genetics , Transcription Factors/metabolism
2.
Br J Psychiatry ; 224(6): 252-257, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38699852

ABSTRACT

Leucine-rich glioma-inactivated 1-antibody-encephalitis is a treatable and potentially reversible cause of cognitive and psychiatric presentations, and may mimic cognitive decline, rapidly progressive dementia and complex psychosis in older patients. This aetiology is of immediate relevance given the alternative treatment pathway required, compared with other conditions presenting with cognitive deficits.


Subject(s)
Autoantibodies , Dementia , Humans , Dementia/therapy , Autoantibodies/blood , Encephalitis/therapy , Encephalitis/diagnosis , Encephalitis/immunology , Intracellular Signaling Peptides and Proteins , Diagnosis, Differential , Aged , Mental Health Services , Female , Male
3.
Brain ; 145(8): 2742-2754, 2022 08 27.
Article in English | MEDLINE | ID: mdl-35680425

ABSTRACT

Autoantibodies against the extracellular domain of the N-methyl-d-aspartate receptor (NMDAR) NR1 subunit cause a severe and common form of encephalitis. To better understand their generation, we aimed to characterize and identify human germinal centres actively participating in NMDAR-specific autoimmunization by sampling patient blood, CSF, ovarian teratoma tissue and, directly from the putative site of human CNS lymphatic drainage, cervical lymph nodes. From serum, both NR1-IgA and NR1-IgM were detected more frequently in NMDAR-antibody encephalitis patients versus controls (both P < 0.0001). Within patients, ovarian teratoma status was associated with a higher frequency of NR1-IgA positivity in serum (OR = 3.1; P < 0.0001) and CSF (OR = 3.8, P = 0.047), particularly early in disease and before ovarian teratoma resection. Consistent with this immunoglobulin class bias, ovarian teratoma samples showed intratumoral production of both NR1-IgG and NR1-IgA and, by single cell RNA sequencing, contained expanded highly-mutated IgA clones with an ovarian teratoma-restricted B cell population. Multiplex histology suggested tertiary lymphoid architectures in ovarian teratomas with dense B cell foci expressing the germinal centre marker BCL6, CD21+ follicular dendritic cells, and the NR1 subunit, alongside lymphatic vessels and high endothelial vasculature. Cultured teratoma explants and dissociated intratumoral B cells secreted NR1-IgGs in culture. Hence, ovarian teratomas showed structural and functional evidence of NR1-specific germinal centres. On exploring classical secondary lymphoid organs, B cells cultured from cervical lymph nodes of patients with NMDAR-antibody encephalitis produced NR1-IgG in 3/7 cultures, from patients with the highest serum NR1-IgG levels (P < 0.05). By contrast, NR1-IgG secretion was observed neither from cervical lymph nodes in disease controls nor in patients with adequately resected ovarian teratomas. Our multimodal evaluations provide convergent anatomical and functional evidence of NMDAR-autoantibody production from active germinal centres within both intratumoral tertiary lymphoid structures and traditional secondary lymphoid organs, the cervical lymph nodes. Furthermore, we develop a cervical lymph node sampling protocol that can be used to directly explore immune activity in health and disease at this emerging neuroimmune interface.


Subject(s)
Anti-N-Methyl-D-Aspartate Receptor Encephalitis , Lymphatic Vessels , Teratoma , Autoantibodies , Female , Germinal Center , Humans , Immunoglobulin A , Immunoglobulin G , Ovarian Neoplasms , Receptors, N-Methyl-D-Aspartate
4.
J Biol Chem ; 295(10): 2948-2958, 2020 03 06.
Article in English | MEDLINE | ID: mdl-31914405

ABSTRACT

Forkhead box N1 (FOXN1) is a member of the forkhead box family of transcription factors and plays an important role in thymic epithelial cell differentiation and development. FOXN1 mutations in humans and mice give rise to the "nude" phenotype, which is marked by athymia. FOXN1 belongs to a subset of the FOX family that recognizes an alternative forkhead-like (FHL) consensus sequence (GACGC) that is different from the more widely recognized forkhead (FKH) sequence RYAAAYA (where R is purine, and Y is pyrimidine). Here, we present the FOXN1 structure in complex with DNA containing an FHL motif at 1.6 Å resolution, in which the DNA sequence is recognized by a mixture of direct and water-mediated contacts provided by residues in an α-helix inserted in the DNA major groove (the recognition helix). Comparisons with the structure of other FOX family members revealed that the FKH and FHL DNA sequences are bound in two distinct modes, with partially different registers for the protein DNA contacts. We identified a single alternative rotamer within the recognition helix itself as an important determinant of DNA specificity and found protein sequence features in the recognition helix that could be used to predict the specificity of other FOX family members. Finally, we demonstrate that the C-terminal region of FOXN1 is required for high-affinity DNA binding and that FOXN1 has a significantly reduced affinity for DNA that contains 5'-methylcytosine, which may have implications for the role of FOXN1 in thymic involution.


Subject(s)
DNA/metabolism , Forkhead Transcription Factors/metabolism , Amino Acid Sequence , Base Sequence , Binding Sites , Crystallography, X-Ray , DNA/chemistry , DNA Methylation , Electrophoretic Mobility Shift Assay , Forkhead Transcription Factors/chemistry , Forkhead Transcription Factors/genetics , Humans , Protein Binding , Protein Conformation, alpha-Helical , Protein Structure, Tertiary , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Sequence Alignment
5.
RNA Biol ; 17(12): 1741-1753, 2020 12.
Article in English | MEDLINE | ID: mdl-32597303

ABSTRACT

RNA-seq is the standard method for profiling gene expression in many biological systems. Due to the wide dynamic range and complex nature of the transcriptome, RNA-seq provides an incomplete characterization, especially of lowly expressed genes and transcripts. Targeted RNA sequencing (RNA CaptureSeq) focuses sequencing on genes of interest, providing exquisite sensitivity for transcript detection and quantification. However, uses of CaptureSeq have focused on bulk samples and its performance on very small populations of cells is unknown. Here we show CaptureSeq greatly enhances transcriptomic profiling of target genes in ultra-low-input samples and provides equivalent performance to that on bulk samples. We validate the performance of CaptureSeq using multiple probe sets on samples of iPSC-derived cortical neurons. We demonstrate up to 275-fold enrichment for target genes, the detection of 10% additional genes and a greater than 5-fold increase in identified gene isoforms. Analysis of spike-in controls demonstrated CaptureSeq improved both detection sensitivity and expression quantification. Comparison to the CORTECON database of cerebral cortex development revealed CaptureSeq enhanced the identification of sample differentiation stage. CaptureSeq provides sensitive, reliable and quantitative expression measurements on hundreds-to-thousands of target genes from ultra-low-input samples and has the potential to greatly enhance transcriptomic profiling when samples are limiting.


Subject(s)
Gene Expression Profiling , High-Throughput Nucleotide Sequencing , Sequence Analysis, RNA , Transcriptome , Cell Differentiation/genetics , Computational Biology/methods , Gene Expression Profiling/methods , High-Throughput Nucleotide Sequencing/methods , Humans , Neurons/cytology , Neurons/metabolism , Sequence Analysis, RNA/methods , Transcription Factors/metabolism
6.
Hum Mol Genet ; 26(1): 79-89, 2017 01 01.
Article in English | MEDLINE | ID: mdl-27798116

ABSTRACT

Dense genotyping approaches have revealed much about the genetic architecture both of gene expression and disease susceptibility. However, assigning causality to genetic variants associated with a transcriptomic or phenotypic trait presents a far greater challenge. The development of epigenomic resources by ENCODE, the Epigenomic Roadmap and others has led to strategies that seek to infer the likely functional variants underlying these genome-wide association signals. It is known, for example, that such variants tend to be located within areas of open chromatin, as detected by techniques such as DNase-seq and FAIRE-seq. We aimed to assess what proportion of variants associated with phenotypic or transcriptomic traits in the human brain are located within transcription factor binding sites. The bioinformatic tools, Wellington and HINT, were used to infer transcription factor footprints from existing DNase-seq data derived from central nervous system tissues with high spatial resolution. This dataset was then employed to assess the likely contribution of altered transcription factor binding to both expression quantitative trait loci (eQTL) and genome-wide association study (GWAS) signals. Surprisingly, we show that most haplotypes associated with GWAS or eQTL phenotypes are located outside of DNase-seq footprints. This could imply that DNase-seq footprinting is too insensitive an approach to identify a large proportion of true transcription factor binding sites. Importantly, this suggests that prioritising variants for genome engineering studies to establish causality will continue to be frustrated by an inability of footprinting to identify the causative variant within a haplotype.


Subject(s)
Brain Diseases/pathology , Brain/pathology , DNA Footprinting/methods , Deoxyribonuclease I/metabolism , Haplotypes/genetics , Quantitative Trait Loci/genetics , Transcription Factors/metabolism , Binding Sites , Brain/metabolism , Brain Diseases/genetics , Brain Diseases/metabolism , Chromatin/metabolism , Chromatin Immunoprecipitation , Computational Biology/methods , Databases, Factual , Gene Expression Regulation , Genetic Variation/genetics , Genome, Human , Genome-Wide Association Study , Genotype , High-Throughput Nucleotide Sequencing/methods , Humans , Molecular Sequence Annotation , Phenotype , Protein Binding , Sequence Analysis, DNA/methods
7.
Hum Mol Genet ; 25(5): 989-1000, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26740550

ABSTRACT

Induced pluripotent stem cell (iPSC)-derived cortical neurons potentially present a powerful new model to understand corticogenesis and neurological disease. Previous work has established that differentiation protocols can produce cortical neurons, but little has been done to characterize these at cellular resolution. In particular, it is unclear to what extent in vitro two-dimensional, relatively disordered culture conditions recapitulate the development of in vivo cortical layer identity. Single-cell multiplex reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was used to interrogate the expression of genes previously implicated in cortical layer or phenotypic identity in individual cells. Totally, 93.6% of single cells derived from iPSCs expressed genes indicative of neuronal identity. High proportions of single neurons derived from iPSCs expressed glutamatergic receptors and synaptic genes. And, 68.4% of iPSC-derived neurons expressing at least one layer marker could be assigned to a laminar identity using canonical cortical layer marker genes. We compared single-cell RNA-seq of our iPSC-derived neurons to available single-cell RNA-seq data from human fetal and adult brain and found that iPSC-derived cortical neurons closely resembled primary fetal brain cells. Unexpectedly, a subpopulation of iPSC-derived neurons co-expressed canonical fetal deep and upper cortical layer markers. However, this appeared to be concordant with data from primary cells. Our results therefore provide reassurance that iPSC-derived cortical neurons are highly similar to primary cortical neurons at the level of single cells but suggest that current layer markers, although effective, may not be able to disambiguate cortical layer identity in all cells.


Subject(s)
Cerebral Cortex/metabolism , Induced Pluripotent Stem Cells/metabolism , Nerve Tissue Proteins/metabolism , Neurogenesis/genetics , Neurons/metabolism , Transcriptome , Adult , Aged , Biomarkers/metabolism , Cell Differentiation , Cell Line , Cerebral Cortex/cytology , Female , Fetus , Fibroblasts/cytology , Fibroblasts/metabolism , Gene Expression Profiling , Gene Expression Regulation, Developmental , Humans , Induced Pluripotent Stem Cells/cytology , Nerve Tissue Proteins/genetics , Neurons/cytology , Real-Time Polymerase Chain Reaction , Receptors, Glutamate/genetics , Receptors, Glutamate/metabolism , Sequence Analysis, RNA , Single-Cell Analysis
9.
Hum Mol Genet ; 23(4): 942-8, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-24092328

ABSTRACT

Genome-wide association studies (GWASs) have shown that approximately 60 genetic variants influence the risk of developing multiple sclerosis (MS). Our aim was to identify the cell types in which these variants are active. We used available data on MS-associated single nucleotide polymorphisms (SNPs) and deoxyribonuclease I hypersensitive sites (DHSs) from 112 different cell types. Genomic intervals were tested for overlap using the Genomic Hyperbrowser. The expression profile of the genes located nearby MS-associated SNPs was assessed using the software GRAIL (Gene Relationships Across Implicated Loci). Genomic regions associated with MS were significantly enriched for a number of immune DHSs and in particular T helper (Th) 1, Th17, CD8+ cytotoxic T cells, CD19+ B cells and CD56+ natural killer (NK) cells (enrichment = 2.34, 2.19, 2.27, 2.05 and 1.95, respectively; P < 0.0001 for all of them). Similar results were obtained when genomic regions with suggestive association with MS and additional immune-mediated traits were investigated. Several new candidate MS-associated genes located within regions of suggestive association were identified by GRAIL (CARD11, FCRL2, CHST12, SYK, TCF7, SOCS1, NFKBIZ and NPAS1). Genetic data indicate that Th1, Th17, cytotoxic T, B and NK cells play a prominent role in the etiology of MS. Regions with confirmed and suggestive association have a similar immunological profile, indicating that many SNPs truly influencing the risk of MS actually fail to reach genome-wide significance. Finally, similar cell types are involved in the etiology of other immune-mediated diseases.


Subject(s)
Multiple Sclerosis/genetics , Deoxyribonucleases/chemistry , Epistasis, Genetic , Genetic Predisposition to Disease , Genome-Wide Association Study , Hep G2 Cells , Humans , Polymorphism, Single Nucleotide
11.
BMC Med Educ ; 14: 225, 2014 Oct 21.
Article in English | MEDLINE | ID: mdl-25335431

ABSTRACT

BACKGROUND: Medical students perceive neurology to be a difficult subject, a phenomenon described as "neurophobia". Studies investigating student attitudes towards neurology have so far been limited by small sample sizes as a consequence of being conducted within a single medical school or region. We aimed to conduct the first national survey of the perception of neurology among UK medical students. METHODS: A 24 question online survey was designed and distributed in the form of a web-link to all UK medical schools. Responses were collected for 10 weeks with reminders sent at 3 and 6 weeks. A prize-draw of £300 was offered upon completion of the survey. RESULTS: 2877 medical students from 25 of 31 medical schools responded. Students found neurology to be significantly more difficult than other specialties and were least comfortable drawing up a neurological differential diagnosis compared to other specialties (p < 0.0001 for neurology vs. each of the other specialties). Neuroanatomy was regarded as the most important factor contributing to neurology being perceived as difficult. CONCLUSIONS: The findings of the first national survey addressing this issue are consistent with previous research. The perception of neurology remains unchanged, in contrast to the rapidly changing demands of neurological care in an ageing population. Neurological examination and formulating a differential diagnosis are important skills in any medical specialty, and combatting "neurophobia" in medical students is therefore essential.


Subject(s)
Career Choice , Education, Medical, Undergraduate/statistics & numerical data , Neurology/education , Students, Medical/statistics & numerical data , Surveys and Questionnaires , Adult , Cross-Sectional Studies , Education, Medical, Undergraduate/methods , Educational Measurement , Female , Humans , Male , Perception , Population Surveillance , Schools, Medical/statistics & numerical data , Students, Medical/psychology , United Kingdom
12.
Ann Clin Transl Neurol ; 11(4): 1053-1058, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38303486

ABSTRACT

Patient-reported quality-of-life (QoL) and carer impacts are not reported after leucine-rich glioma-inactivated 1-antibody encephalitis (LGI1-Ab-E). From 60 patients, 85% (51 out of 60) showed one abnormal score across QoL assessments and 11 multimodal validated questionnaires. Compared to the premorbid state, QoL significantly deteriorated (p < 0.001) and, at a median of 41 months, fatigue was its most important predictor (p = 0.025). In total, 51% (26 out of 51) of carers reported significant burden. An abbreviated five-item battery explained most variance in QoL. Wide-ranging impacts post-LGI1-Ab-E include decreased QoL and high caregiver strain. We identify a rapid method to capture QoL in routine clinic or clinical trial settings.


Subject(s)
Encephalitis , Glioma , Humans , Leucine , Quality of Life , Intracellular Signaling Peptides and Proteins , Autoantibodies , Fatigue/etiology
13.
JAMA Neurol ; 81(5): 525-533, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38497971

ABSTRACT

Importance: Rapid and accurate diagnosis of autoimmune encephalitis encourages prompt initiation of immunotherapy toward improved patient outcomes. However, clinical features alone may not sufficiently narrow the differential diagnosis, and awaiting autoantibody results can delay immunotherapy. Objective: To identify simple magnetic resonance imaging (MRI) characteristics that accurately distinguish 2 common forms of autoimmune encephalitis, LGI1- and CASPR2-antibody encephalitis (LGI1/CASPR2-Ab-E), from 2 major differential diagnoses, viral encephalitis (VE) and Creutzfeldt-Jakob disease (CJD). Design, Setting, and Participants: This cross-sectional study involved a retrospective, blinded analysis of the first available brain MRIs (taken 2000-2022) from 192 patients at Oxford University Hospitals in the UK and Mayo Clinic in the US. These patients had LGI1/CASPR2-Ab-E, VE, or CJD as evaluated by 2 neuroradiologists (discovery cohort; n = 87); findings were validated in an independent cohort by 3 neurologists (n = 105). Groups were statistically compared with contingency tables. Data were analyzed in 2023. Main Outcomes and Measures: MRI findings including T2 or fluid-attenuated inversion recovery (FLAIR) hyperintensities, swelling or volume loss, presence of gadolinium contrast enhancement, and diffusion-weighted imaging changes. Correlations with clinical features. Results: Among 192 participants with MRIs reviewed, 71 were female (37%) and 121 were male (63%); the median age was 66 years (range, 19-92 years). By comparison with VE and CJD, in LGI1/CASPR2-Ab-E, T2 and/or FLAIR hyperintensities were less likely to extend outside the temporal lobe (3/42 patients [7%] vs 17/18 patients [94%] with VE; P < .001, and 3/4 patients [75%] with CJD; P = .005), less frequently exhibited swelling (12/55 [22%] with LGI1/CASPR2-Ab-E vs 13/22 [59%] with VE; P = .003), and showed no diffusion restriction (0 patients vs 16/22 [73%] with VE and 8/10 [80%] with CJD; both P < .001) and rare contrast enhancement (1/20 [5%] vs 7/17 [41%] with VE; P = .01). These findings were validated in an independent cohort and generated an area under the curve of 0.97, sensitivity of 90%, and specificity of 95% among cases with T2/FLAIR hyperintensity in the hippocampus and/or amygdala. Conclusions and Relevance: In this study, T2 and/or FLAIR hyperintensities confined to the temporal lobes, without diffusion restriction or contrast enhancement, robustly distinguished LGI1/CASPR2-Ab-E from key differential diagnoses. These observations should assist clinical decision-making toward expediting immunotherapy. Their generalizability to other forms of autoimmune encephalitis and VE should be examined in future studies.


Subject(s)
Autoantibodies , Encephalitis , Intracellular Signaling Peptides and Proteins , Magnetic Resonance Imaging , Membrane Proteins , Nerve Tissue Proteins , Humans , Male , Female , Aged , Intracellular Signaling Peptides and Proteins/immunology , Middle Aged , Magnetic Resonance Imaging/methods , Cross-Sectional Studies , Autoantibodies/immunology , Encephalitis/diagnostic imaging , Encephalitis/immunology , Encephalitis/pathology , Retrospective Studies , Nerve Tissue Proteins/immunology , Membrane Proteins/immunology , Adult , Aged, 80 and over , Creutzfeldt-Jakob Syndrome/diagnostic imaging , Creutzfeldt-Jakob Syndrome/immunology , Creutzfeldt-Jakob Syndrome/pathology , Diagnosis, Differential , Brain/diagnostic imaging , Brain/pathology , Hashimoto Disease/diagnostic imaging , Hashimoto Disease/immunology , Young Adult
14.
Genome Res ; 20(10): 1352-60, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20736230

ABSTRACT

Initially thought to play a restricted role in calcium homeostasis, the pleiotropic actions of vitamin D in biology and their clinical significance are only now becoming apparent. However, the mode of action of vitamin D, through its cognate nuclear vitamin D receptor (VDR), and its contribution to diverse disorders, remain poorly understood. We determined VDR binding throughout the human genome using chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq). After calcitriol stimulation, we identified 2776 genomic positions occupied by the VDR and 229 genes with significant changes in expression in response to vitamin D. VDR binding sites were significantly enriched near autoimmune and cancer associated genes identified from genome-wide association (GWA) studies. Notable genes with VDR binding included IRF8, associated with MS, and PTPN2 associated with Crohn's disease and T1D. Furthermore, a number of single nucleotide polymorphism associations from GWA were located directly within VDR binding intervals, for example, rs13385731 associated with SLE and rs947474 associated with T1D. We also observed significant enrichment of VDR intervals within regions of positive selection among individuals of Asian and European descent. ChIP-seq determination of transcription factor binding, in combination with GWA data, provides a powerful approach to further understanding the molecular bases of complex diseases.


Subject(s)
Autoimmune Diseases/genetics , Chromatin Immunoprecipitation , Evolution, Molecular , Genome-Wide Association Study , Receptors, Calcitriol/metabolism , Vitamin D/metabolism , Binding Sites , Crohn Disease/genetics , Diabetes Mellitus, Type 1/genetics , Humans , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Multiple Sclerosis/genetics , Protein Binding , Protein Tyrosine Phosphatase, Non-Receptor Type 2/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 2/metabolism , Sequence Analysis, DNA/methods
15.
BMC Med ; 11: 163, 2013 Jul 12.
Article in English | MEDLINE | ID: mdl-23849224

ABSTRACT

BACKGROUND: Vitamin D insufficiency has been implicated in autoimmunity. ChIP-seq experiments using immune cell lines have shown that vitamin D receptor (VDR) binding sites are enriched near regions of the genome associated with autoimmune diseases. We aimed to investigate VDR binding in primary CD4+ cells from healthy volunteers. METHODS: We extracted CD4+ cells from nine healthy volunteers. Each sample underwent VDR ChIP-seq. Our results were analyzed in relation to published ChIP-seq and RNA-seq data in the Genomic HyperBrowser. We used MEMEChIP for de novo motif discovery. 25-Hydroxyvitamin D levels were measured using liquid chromatography-tandem mass spectrometry and samples were divided into vitamin D sufficient (25(OH)D ≥75 nmol/L) and insufficient/deficient (25(OH)D <75 nmol/L) groups. RESULTS: We found that the amount of VDR binding is correlated with the serum level of 25-hydroxyvitamin D (r = 0.92, P= 0.0005). In vivo VDR binding sites are enriched for autoimmune disease associated loci, especially when 25-hydroxyvitamin D levels (25(OH)D) were sufficient (25(OH)D ≥75: 3.13-fold, P<0.0001; 25(OH)D <75: 2.76-fold, P<0.0001; 25(OH)D ≥75 enrichment versus 25(OH)D <75 enrichment: P= 0.0002). VDR binding was also enriched near genes associated specifically with T-regulatory and T-helper cells in the 25(OH)D ≥75 group. MEME ChIP did not identify any VDR-like motifs underlying our VDR ChIP-seq peaks. CONCLUSION: Our results show a direct correlation between in vivo 25-hydroxyvitamin D levels and the number of VDR binding sites, although our sample size is relatively small. Our study further implicates VDR binding as important in gene-environment interactions underlying the development of autoimmunity and provides a biological rationale for 25-hydroxyvitamin D sufficiency being based at 75 nmol/L. Our results also suggest that VDR binding in response to physiological levels of vitamin D occurs predominantly in a VDR motif-independent manner.


Subject(s)
Autoimmune Diseases/blood , CD4-Positive T-Lymphocytes/metabolism , Protein Array Analysis/methods , Receptors, Calcitriol/blood , Vitamin D/analogs & derivatives , Amino Acid Motifs , Amino Acid Sequence , Autoimmune Diseases/genetics , Autoimmune Diseases/pathology , Binding Sites/genetics , CD4-Positive T-Lymphocytes/pathology , Genomics/methods , Humans , Primary Cell Culture , Receptors, Calcitriol/genetics , Vitamin D/blood
16.
Nat Commun ; 14(1): 4071, 2023 07 10.
Article in English | MEDLINE | ID: mdl-37429879

ABSTRACT

The network of thymic stromal cells provides essential niches with unique molecular cues controlling T cell development and selection. Recent single-cell RNA sequencing studies have uncovered previously unappreciated transcriptional heterogeneity among thymic epithelial cells (TEC). However, there are only very few cell markers that allow a comparable phenotypic identification of TEC. Here, using massively parallel flow cytometry and machine learning, we deconvoluted known TEC phenotypes into novel subpopulations. Using CITEseq, these phenotypes were related to corresponding TEC subtypes defined by the cells' RNA profiles. This approach allowed the phenotypic identification of perinatal cTEC and their physical localisation within the cortical stromal scaffold. In addition, we demonstrate the dynamic change in the frequency of perinatal cTEC in response to developing thymocytes and reveal their exceptional efficiency in positive selection. Collectively, our study identifies markers that allow for an unprecedented dissection of the thymus stromal complexity, as well as physical isolation of TEC populations and assignment of specific functions to individual TEC subtypes.


Subject(s)
Epithelial Cells , Thymocytes , Female , Pregnancy , Humans , Cell Differentiation , Cues , RNA
17.
Dis Model Mech ; 15(10)2022 10 01.
Article in English | MEDLINE | ID: mdl-36254682

ABSTRACT

Alzheimer's disease (AD) is the most common form of dementia, and risk-influencing genetics implicates microglia and neuroimmunity in the pathogenesis of AD. Induced pluripotent stem cell (iPSC)-derived microglia (iPSC-microglia) are increasingly used as a model of AD, but the relevance of historical immune stimuli to model AD is unclear. We performed a detailed cross-comparison over time on the effects of combinatory stimulation of iPSC-microglia, and in particular their relevance to AD. We used single-cell RNA sequencing to measure the transcriptional response of iPSC-microglia after 24 h and 48 h of stimulation with prostaglandin E2 (PGE2) or lipopolysaccharide (LPS)+interferon gamma (IFN-γ), either alone or in combination with ATPγS. We observed a shared core transcriptional response of iPSC-microglia to ATPγS and to LPS+IFN-γ, suggestive of a convergent mechanism of action. Across all conditions, we observed a significant overlap, although directional inconsistency to genes that change their expression levels in human microglia from AD patients. Using a data-led approach, we identify a common axis of transcriptomic change across AD genetic mouse models of microglia and show that only LPS provokes a transcriptional response along this axis in mouse microglia and LPS+IFN-γ in human iPSC-microglia. This article has an associated First Person interview with the first author of the paper.


Subject(s)
Alzheimer Disease , Microglia , Alzheimer Disease/metabolism , Animals , Dinoprostone/metabolism , Disease Models, Animal , Humans , Interferon-gamma/metabolism , Lipopolysaccharides/metabolism , Lipopolysaccharides/pharmacology , Mice , Microglia/pathology , Transcriptome/genetics
18.
Sci Adv ; 8(19): eabm9844, 2022 May 13.
Article in English | MEDLINE | ID: mdl-35559672

ABSTRACT

The thymic stroma is composed of epithelial and nonepithelial cells providing separate microenvironments controlling homing, differentiation, and selection of hematopoietic precursor cells to functional T cells. Here, we explore at single-cell resolution the complex composition and dynamic changes of the nonepithelial stromal compartment across different developmental stages in the human and mouse thymus, and in an experimental model of the DiGeorge syndrome, the most common form of human thymic hypoplasia. The detected gene expression signatures identify previously unknown stromal subtypes and relate their individual molecular profiles to separate differentiation trajectories and functions, revealing an unprecedented heterogeneity of different cell types that emerge at discrete developmental stages and vary in their expression of key regulatory signaling circuits and extracellular matrix components. Together, these findings highlight the dynamic complexity of the nonepithelial thymus stroma and link this to separate instructive roles essential for normal thymus organogenesis and tissue maintenance.

19.
BMC Med ; 9: 1, 2011 Jan 10.
Article in English | MEDLINE | ID: mdl-21219637

ABSTRACT

BACKGROUND: Venous thromboembolism (VTE) is a common complication during and after a hospital admission. Although it is mainly considered a complication of surgery, it often occurs in people who have not undergone surgery, with recent evidence suggesting that immune-mediated diseases may play a role in VTE risk. We, therefore, decided to study the risk of deep vein thrombosis (DVT) and pulmonary embolism (PE) in people admitted to hospital with a range of immune-mediated diseases. METHODS: We analysed databases of linked statistical records of hospital admissions and death certificates for the Oxford Record Linkage Study area (ORLS1:1968 to 1998 and ORLS2:1999 to 2008) and the whole of England (1999 to 2008). Rate ratios for VTE were determined, comparing immune-mediated disease cohorts with comparison cohorts. RESULTS: Significantly elevated risks of VTE were found, in all three populations studied, in people with a hospital record of admission for autoimmune haemolytic anaemia, chronic active hepatitis, dermatomyositis/polymyositis, type 1 diabetes mellitus, multiple sclerosis, myasthenia gravis, myxoedema, pemphigus/pemphigoid, polyarteritis nodosa, psoriasis, rheumatoid arthritis, Sjogren's syndrome, and systemic lupus erythematosus. Rate ratios were considerably higher for some of these diseases than others: for example, for systemic lupus erythematosus the rate ratios were 3.61 (2.36 to 5.31) in the ORLS1 population, 4.60 (3.19 to 6.43) in ORLS2 and 3.71 (3.43 to 4.02) in the England dataset. CONCLUSIONS: People admitted to hospital with immune-mediated diseases may be at an increased risk of subsequent VTE. Our findings need independent confirmation or refutation; but, if confirmed, there may be a role for thromboprophylaxis in some patients with these diseases.


Subject(s)
Hospital Records , Immune System Diseases/complications , Patient Admission , Venous Thromboembolism/etiology , Case-Control Studies , Cohort Studies , Confidence Intervals , Female , Humans , Male , Risk Factors , Time Factors
20.
Eur J Clin Invest ; 41(11): 1254-8, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21418205

ABSTRACT

BACKGROUND: Research using experimental autoimmune encephalitis (EAE) models accounts for almost 20% of the papers. published in multiple sclerosis (MS). METHODS: We performed a literature review of papers indexed with ISI Web of Science on EAE and MS over the last 30 years and a detailed analysis of studies of molecular pathways in EAE published in 2008 and 2009. RESULTS: The impact of EAE studies declines more rapidly than other studies published on MS (EAE cited corrected half-life = 4·00 years vs. MS cited corrected half-life = 9·66 years, P < 0·0001). The pathology of EAE differs quite markedly from that observed in the human disease. EAE has implicated many different genes as important to pathogenesis but only a minority of these are supported by human studies. CONCLUSIONS: Future research should critically appraise precisely what is being modelled by EAE before drawing conclusions about human disease.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/immunology , Multiple Sclerosis/immunology , Animals , Disease Models, Animal , Encephalomyelitis, Autoimmune, Experimental/genetics , Genetic Predisposition to Disease , Humans , Multiple Sclerosis/genetics
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