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Erle, D. J.

Publications and source records attributed to Erle, D. J..

18 recordsLinked to original sources

Allergen-responsive T helper type 2 cells revealed by high-dimensional profiling in allergen challenged human airways

Asthma is a chronic inflammatory disease affecting over 300 million people worldwide. This disease has multiple underlying etiologies, and a major endotype of asthma is characterized by cellular and molecular signatures of type 2 (allergic) inflammation. In this study we conducted bronchoscopies with airway segmental allergen challenge in allergic asthmatics to dissect airway responses to allergen. Using mass cytometry and single-cell RNA sequencing, we characterized with high resolution the airway immune landscape before and after allergen challenge and the heterogeneity present between subjects. This heterogeneity generally falls along a type 1/ type 2 axis. In type 2 high individuals, we identified allergen-reactive Th2 cells by using TCR sequences to barcode clonal T cell populations in single-cell genomic and activation-induced marker expression assays. These potentially pathogenic Th2 cell clones were present systemically and expanded following allergen challenge, connecting local lung inflammation to systemic clonal Th2 cell dynamics. Th2 cell airway ingress was coordinated with myeloid cell expression of T cell chemoattractants including CCL17 and CCL22. This study provides insight into the molecular and cellular components of allergen-induced tissue inflammation in asthma. Deeper resolution of the T cell response to aeroallergens may inform novel diagnostic and therapeutic strategies for asthma and other allergic airway diseases.

immunology↗

Identification of a multi-omics factor predictive of long COVID in the IMPACC study

Following SARS-CoV-2 infection, [~]10-35% of COVID-19 patients experience long COVID (LC), in which often debilitating symptoms persist for at least three months. Elucidating the biologic underpinnings of LC could identify therapeutic opportunities. We utilized machine learning methods on biologic analytes and patient reported outcome surveys provided over 12 months after hospital discharge from >500 hospitalized COVID-19 patients in the IMPACC cohort to identify a multi-omics "recovery factor". IMPACC participants who experienced LC had lower recovery factor scores compared to participants without LC. Biologic characterization revealed increased levels of plasma proteins associated with inflammation, elevated transcriptional signatures of heme metabolism, and decreased androgenic steroids in LC patients. The recovery factor was also associated with altered circulating immune cell frequencies. Notably, recovery factor scores were predictive of LC occurrence in patients as early as hospital admission, irrespective of acute disease severity. Thus, the recovery factor identifies patients at risk of LC early after SARS-CoV-2 infection and reveals LC biomarkers and potential treatment targets.

systems biology↗

Immediate myeloid depot for SARS-CoV-2 in the human lung

In the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, considerable focus has been placed on a model of viral entry into host epithelial populations, with a separate focus upon the responding immune system dysfunction that exacerbates or causes disease. We developed a precision-cut lung slice model to investigate very early host-viral pathogenesis and found that SARS-CoV-2 had a rapid and specific tropism for myeloid populations in the human lung. Infection of alveolar macrophages was partially dependent upon their expression of ACE2, and the infections were productive for amplifying virus, both findings which were in contrast with their neutralization of another pandemic virus, Influenza A virus (IAV). Compared to IAV, SARS-CoV-2 was extremely poor at inducing interferon-stimulated genes in infected myeloid cells, providing a window of opportunity for modest titers to amplify within these cells. Endotracheal aspirate samples from humans with the acute respiratory distress syndrome (ARDS) from COVID-19 confirmed the lung slice findings, revealing a persistent myeloid depot. In the early phase of SARS-CoV-2 infection, myeloid cells may provide a safe harbor for the virus with minimal immune stimulatory cues being generated, resulting in effective viral colonization and quenching of the immune system.

immunology↗

A conserved immune trajectory of recovery in hospitalized COVID-19 patients

Many studies have provided insights into the immune response to COVID-19; however, little is known about the immunological changes and immune signaling occurring during COVID-19 resolution. Individual heterogeneity and variable disease resolution timelines obscure unifying immune characteristics. Here, we collected and profiled >200 longitudinal peripheral blood samples from patients hospitalized with COVID-19, with other respiratory infections, and healthy individuals, using mass cytometry to measure immune cells and signaling states at single cell resolution. COVID-19 patients showed a unique immune composition and an early, coordinated and elevated immune cell signaling profile, which correlated with early hospital discharge. Intra-patient time course analysis tied to clinically relevant events of recovery revealed a conserved set of immunological processes that accompany, and are unique to, disease resolution and discharge. This immunological process, together with additional changes in CD4 regulatory T cells and basophils, accompanies recovery from respiratory failure and is associated with better clinical outcomes at the time of admission. Our work elucidates the biological timeline of immune recovery from COVID-19 and provides insights into the fundamental processes of COVID-19 resolution in hospitalized patients.

immunology↗

Targeting a central feature of asthma using a cell type-selective IL-13-responsive enhancer

IL-13 is a central mediator of asthma1-3. Here, we used genome-wide approaches to characterize genes and regulatory elements modulated by IL-13 and other asthma-associated cytokines in airway epithelial cells and showed how they can be used for therapeutic purposes. Using bulk and single cell RNA-seq, we found distinctive responses to IL-13, IL-17, and interferons in human bronchial epithelial basal, ciliated, and secretory cells. H3K27ac ChIP-seq revealed that IL-13 had widespread effects on regulatory elements. Detailed characterization of an enhancer of SPDEF, a transcription factor required for pathologic mucin production, revealed that STAT6 and KLF5 binding sites cooperate to drive IL-13-dependent transcription selectively in secretory cells. Using this enhancer to drive CRISPRi and knockdown either SPDEF or the mucin MUC5AC showed the potential use of this approach for asthma therapeutics. This work identifies numerous genes and regulatory elements involved in cell type-selective cytokine responses and showcases their use for therapeutic purposes.

immunology↗

A Pan-Cancer Census of Dominant Tumor Immune Archetypes

Cancers display significant heterogeneity with respect to tissue of origin, driver mutations and other features of the surrounding tissue. It is likely that persistent tumors differentially engage inherent patterns-here Archetypes-of the immune system, to both benefit from a tumor immune microenvironment (TIME) and to disengage tumor-targeting. To discover dominant immune system archetypes, the Immunoprofiler Initiative (IPI) processed 364 individual tumors across 12 cancer types using standardized protocols. Computational clustering of flow cytometry and transcriptomic data obtained from cell sub compartments uncovered archetypes that exist across indications. These Immune composition-based archetypes differentiate tumors based upon unique immune and tumor gene-expression patterns. Archetypes discovered this way also tie closely to well-established classifications of tumor biology. The IPI resource provides a template for understanding cancer immunity as a collection of dominant patterns of immune infiltration and provides a rational path forward to learn how to modulate these patterns to improve therapy. O_FIG O_LINKSMALLFIG WIDTH=182 HEIGHT=200 SRC="FIGDIR/small/441344v1_ufig1.gif" ALT="Figure 1"> View larger version (77K): org.highwire.dtl.DTLVardef@55a5ccorg.highwire.dtl.DTLVardef@f8205corg.highwire.dtl.DTLVardef@1480b8org.highwire.dtl.DTLVardef@eb94e_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Longitudinal single-cell epitope and RNA-sequencing reveals the immunological impact of type 1 interferon autoantibodies in critical COVID-19

Type I interferon (IFN-I) neutralizing autoantibodies have been found in some critical COVID-19 patients; however, their prevalence and longitudinal dynamics across the disease severity scale, and functional effects on circulating leukocytes remain unknown. Here, in 284 COVID-19 patients, we found IFN-I autoantibodies in 19% of critical, 6% of severe and none of the moderate cases. Longitudinal profiling of over 600,000 peripheral blood mononuclear cells using multiplexed single-cell epitope and transcriptome sequencing from 54 COVID-19 patients, 15 non-COVID-19 patients and 11 non-hospitalized healthy controls, revealed a lack of IFN-I stimulated gene (ISG-I) response in myeloid cells from critical cases, including those producing anti-IFN-I autoantibodies. Moreover, surface protein analysis showed an inverse correlation of the inhibitory receptor LAIR-1 with ISG-I expression response early in the disease course. This aberrant ISG-I response in critical patients with and without IFN-I autoantibodies, supports a unifying model for disease pathogenesis involving ISG-I suppression via convergent mechanisms.

immunology↗

The type 2 asthma mediator IL-13 inhibits SARS-CoV-2 infection of bronchial epithelium

RationaleAsthma is associated with chronic changes in the airway epithelium, a key target of SARS-CoV-2. Many epithelial changes are driven by the type 2 cytokine IL-13, but the effects of IL-13 on SARS-CoV-2 infection are unknown. ObjectivesWe sought to discover how IL-13 and other cytokines affect expression of genes encoding SARS-CoV-2-associated host proteins in human bronchial epithelial cells (HBECs) and determine whether IL-13 stimulation alters susceptibility to SARS-CoV-2 infection. MethodsWe used bulk and single cell RNA-seq to identify cytokine-induced changes in SARS-CoV-2-associated gene expression in HBECs. We related these to gene expression changes in airway epithelium from individuals with mild-moderate asthma and chronic obstructive pulmonary disease (COPD). We analyzed effects of IL-13 on SARS-CoV-2 infection of HBECs. Measurements and Main ResultsTranscripts encoding 332 of 342 (97%) SARS-CoV-2-associated proteins were detected in HBECs ([&ge;]1 RPM in 50% samples). 41 (12%) of these mRNAs were regulated by IL-13 (>1.5-fold change, FDR < 0.05). Many IL-13-regulated SARS-CoV-2-associated genes were also altered in type 2 high asthma and COPD. IL-13 pretreatment reduced viral RNA recovered from SARS-CoV-2 infected cells and decreased dsRNA, a marker of viral replication, to below the limit of detection in our assay. Mucus also inhibited viral infection. ConclusionsIL-13 markedly reduces susceptibility of HBECs to SARS-CoV-2 infection through mechanisms that likely differ from those activated by type I interferons. Our findings may help explain reports of relatively low prevalence of asthma in patients diagnosed with COVID-19 and could lead to new strategies for reducing SARS-CoV-2 infection.

cell biology↗

Global Absence and Targeting of Protective Immune States in Severe COVID-19.

While SARS-CoV-2 infection has pleiotropic and systemic effects in some patients, many others experience milder symptoms. We sought a holistic understanding of the severe/mild distinction in COVID-19 pathology, and its origins. We performed a whole-blood preserving single-cell analysis protocol to integrate contributions from all major cell types including neutrophils, monocytes, platelets, lymphocytes and the contents of serum. Patients with mild COVID-19 disease display a coordinated pattern of interferon-stimulated gene (ISG) expression across every cell population and these cells are systemically absent in patients with severe disease. Severe COVID-19 patients also paradoxically produce very high anti-SARS-CoV-2 antibody titers and have lower viral load as compared to mild disease. Examination of the serum from severe patients demonstrates that they uniquely produce antibodies with multiple patterns of specificity against interferon-stimulated cells and that those antibodies functionally block the production of the mild disease-associated ISG-expressing cells. Overzealous and auto-directed antibody responses pit the immune system against itself in many COVID-19 patients and this defines targets for immunotherapies to allow immune systems to provide viral defense. One Sentence SummaryIn severe COVID-19 patients, the immune system fails to generate cells that define mild disease; antibodies in their serum actively prevents the successful production of those cells.

immunology↗

Flow cytometric analysis and purification of airway epithelial cell subsets

The human airway epithelium is essential in homeostasis, and epithelial dysfunction contributes to chronic airway disease. Development of flow cytometric methods to characterize subsets of airway epithelial cells will enable further dissection of airway epithelial biology. Leveraging single cell RNA-sequencing (scRNA-seq) data in combination with known cell type-specific markers, we developed panels of antibodies to characterize and isolate the major airway epithelial subsets (basal, ciliated, and secretory cells) from human bronchial epithelial cell cultures. We also identified molecularly distinct subpopulations of secretory cells and demonstrated cell subset-specific expression of low abundance transcripts and micro-RNAs that are challenging to analyze with current scRNA-seq methods. These new tools will be valuable for analyzing and separating airway epithelial subsets and interrogating airway epithelial biology.

cell biology↗

MPRAudit Quantifies the Fraction of Variance Described by Unknown Features in Massively Parallel Reporter Assays

Transformative advances in molecular technologies, such as massively parallel reporter assays (MPRAs) and CRISPR screens, can efficiently characterize the effects of genetic and genomic variation on cellular phenotypes. Analysis approaches to date have focused on identifying individual genomic regions or genetic variants that perturb a phenotype of interest. In this work, we develop a wholistic framework (MPRAudit) to determine the global contribution of sequence to phenotypic variation across subsets of the entire experiment, opening the door to myriad novel analyses. For example, MPRAudit can reliably estimate the upper limit of predictive performance, the fraction of variation attributed to specific biological categories, and the total contribution of experimental noise. We demonstrate through simulation and application to several types of real MPRA data sets how MPRAudit can lead to an improved understanding of experimental quality, molecular biology, and guide future research. Applying MPRAudit to real MPRA data, we observe that sequence variation is the primary driver of outcome variability, but that known biological categories explain only a fraction of this variance. We conclude that our understanding of how sequence variation impacts phenotype, even at the level of MPRAs, remains open to further scientific discovery.

bioinformatics↗

Massively Parallel Analysis of Human 3' UTRs Reveals that AU-Rich Element Length and Registration Predict mRNA Destabilization

AU-rich elements (AREs) are 3' UTR cis-regulatory elements that regulate the stability of mRNAs. Consensus ARE motifs have been determined, but little is known about how differences in 3' UTR sequences that conform to these motifs affect their function. Here we use functional annotation of sequences from 3' UTRs (fast-UTR), a massively parallel reporter assay (MPRA), to investigate the effects of 41,288 3' UTR sequence fragments from 4,653 transcripts on gene expression and mRNA stability. The library included 9,142 AREs, and incorporated a set of fragments bearing mutations in each ARE. Our analyses demonstrate that the length of an ARE and its registration (the first and last nucleotides of the repeating ARE motif) have significant effects on gene expression and stability. Based on this finding, we propose improved ARE classification and concomitant methods to categorize and predict the effect of AREs on gene expression and stability. Our new approach explains 64{+/-}13% of the contribution of AREs to the stability of human 3' UTRs in Jurkat cells and predicts ARE activity in an unrelated cell type. Finally, to investigate the advantages of our general experimental design for annotating 3' UTR elements we examine other motifs including constitutive decay elements (CDEs), where we show that the length of the CDE stem-loop has a significant impact on steady-state expression and mRNA stability. We conclude that fast-UTR, in conjunction with our analytical approach, can produce improved yet simple sequence-based rules for predicting the activity of human 3' UTRs containing functional motifs.

genomics↗

Efficient RNP-directed human gene targeting reveals SPDEF is required for IL-13-induced mucostasis

Primary human bronchial epithelial cell (HBEC) cultures are a useful model for studies of lung health and major airway diseases. However, mechanistic studies have been limited by our ability to selectively disrupt specific genes in these cells. Here we optimize methods for gene targeting in HBECs by direct delivery of single guide RNA (sgRNA) and recombinant Cas9 (rCas9) complexes by electroporation, without a requirement for plasmids, viruses, or antibiotic selection. Variations in the method of delivery, sgRNA and rCas9 concentrations, and sgRNA sequences all had effects on targeting efficiency, allowing for predictable control of the extent of gene targeting and for near complete disruption of gene expression. To demonstrate the value of this system, we targeted SPDEF, which encodes a transcription factor previously shown to be essential for the differentiation of MUC5AC-producing goblet cells in mouse models of asthma. Targeting SPDEF led to proportional decreases in MUC5AC expression in HBECs stimulated with IL-13, a central mediator of allergic asthma. Near-complete targeting of SPDEF abolished IL-13-induced MUC5AC expression and goblet cell differentiation. In addition, targeting of SPDEF prevented IL-13-induced impairment of mucociliary clearance, which is likely to be an important contributor to airway obstruction, morbidity, and mortality in asthma. We conclude that direct delivery of sgRNA and rCas9 complexes allows for predictable and efficient gene targeting and enables mechanistic studies of disease-relevant pathways in primary HBECs.

molecular biology↗

Comparison of miRNA profiling methods using synthetic miRNA pools and standardized exRNA samples reveals substantial performance differences

MicroRNAs (miRNAs) found in biofluids play functional roles in health and in disease pathogenesis, underpinning their potential as clinical biomarkers. Several platforms for measurement of extracellular RNAs have recently become available. We evaluated the reproducibility, accuracy, sensitivity, and specificity of four miRNA quantification platforms, including one widely used discovery approach (small RNA-seq) and three targeted platforms (FirePlex, EdgeSeq, and nCounter). Using pools of synthetic miRNAs, we observed that reproducibility was highest for RNA-seq and EdgeSeq, that all three targeted platforms had lower bias than RNA-seq, and that RNA-seq had the best ability to distinguish between present and absent sequences. Overall reproducibility was lower for plasma samples than synthetic miRNA pools. We compared expression of placental miRNAs in plasma from pregnant and non-pregnant women and observed expected differences with RNA-seq and EdgeSeq, but not FirePlex or nCounter. We conclude that differences in performance among miRNA profiling platforms impact their relative utility as potential assay systems for clinical biomarkers.

genomics↗

A global map of RNA binding protein occupancy guides functional dissection of post-transcriptional regulation of the T cell transcriptome

RNA binding proteins (RBPs) mediate constitutive RNA metabolism and gene specific regulatory interactions. To identify RNA cis-regulatory elements, we developed GCLiPP, a biochemical technique for detecting RBP occupancy transcriptome-wide. GCLiPP sequence tags corresponded with known RBP binding sites, specifically correlating to abundant cytosolic RBPs. To demonstrate the utility of our occupancy profiles, we performed functional dissection of 3' UTRs with CRISPR/Cas9 genome editing. Two RBP occupied sites in the CD69 3' UTR destabilized the transcript of this key regulator of lymphocyte tissue egress. Comparing human Jurkat T cells and mouse primary T cells uncovered hundreds of biochemically shared peaks of GCLiPP signal across homologous regions of human and mouse 3' UTRs, including a cis-regulatory element that governs the stability of the mRNA that encodes the proto-oncogene PIM3 in both species. Our GCLiPP datasets provide a rich resource for investigation of post-transcriptional regulation in the immune system.

genomics↗

Detection of succinate by intestinal tuft cells triggers a type 2 innate immune circuit

Initiation of immune responses requires innate immune sensing, but immune detection of the helminths, protists, and allergens that stimulate type 2 immunity remains poorly understood. In the small intestine, type 2 immune responses are regulated by a tuft cell-ILC2 signaling circuit. Tuft cells express components of a canonical taste transduction pathway, including the membrane channel TRPM5, but the ligands and receptors that activate tuft cells in the small intestine are unknown. Here we identify succinate as the first ligand that activates intestinal tuft cells to initiate type 2 immune responses. Using mRNA-Seq on tuft cells from different tissues, we show that all tuft cells express the intracellular taste transduction pathway, but expression of upstream receptors is tissue-specific. In the small intestine, tuft cells express the succinate receptor SUCNR1. Remarkably, providing succinate in drinking water is sufficient to induce a multifaceted type 2 immune response in the murine small intestine, involving all known components of the tuft-ILC2 circuit. The helminth Nippostrongylus brasiliensis secretes succinate as a metabolite, and sensing of both succinate and N. brasiliensis requires tuft cells and TRPM5, suggesting a novel paradigm in which type 2 immunity monitors microbial metabolism. Manipulation of succinate sensing may have therapeutic benefit in numerous intestinal diseases.

immunology↗

Large differences in small RNA composition between human biofluids

Extracellular miRNAs and other small RNAs are implicated in cellular communication and may be useful as disease biomarkers. We systematically compared small RNAs in 12 human biofluid types using RNA-seq. miRNAs and tRNA-derived RNAs (tDRs) accounted for the majority of mapped reads in all biofluids, but the ratio of miRNA to tDR reads varied from 72 in plasma to 0.004 in bile. miRNA levels were highly correlated across all biofluids but levels of some miRNAs differed markedly between biofluids. tDR populations differed extensively between biofluids. Y RNA fragments were seen in all biofluids and accounted for >10% of reads in blood plasma, serum, and CSF. Reads mapping exclusively to piRNAs were very rare except in seminal plasma. These results demonstrate extensive differences in small RNAs between human biofluids and provide a useful resource for investigating extracellular RNA biology and developing biomarkers.

genomics↗

Accuracy, Reproducibility And Bias Of Next Generation Sequencing For Quantitative Small RNA Profiling: A Multiple Protocol Study Across Multiple Laboratories

Small RNA-seq is increasingly being used for profiling of small RNAs. Quantitative characteristics of long RNA-seq have been extensively described, but small RNA-seq involves fundamentally different methods for library preparation, with distinct protocols and technical variations that have not been fully and systematically studied. We report here the results of a study using common references (synthetic RNA pools of defined composition, as well as plasma-derived RNA) to evaluate the accuracy, reproducibility and bias of small RNA-seq library preparation for five distinct protocols and across nine different laboratories. We observed protocol-specific and sequence-specific bias, which was ameliorated using adapters for ligation with randomized end-nucleotides, and computational correction factors. Despite this technical bias, relative quantification using small RNA-seq was remarkably accurate and reproducible, even across multiple laboratories using different methods. These results provide strong evidence for the feasibility of reproducible cross-laboratory small RNA-seq studies, even those involving analysis of data generated using different protocols.

genomics↗