RESUMEN
Repetitive exposure to antigen in chronic infection and cancer drives T cell exhaustion, limiting adaptive immunity. In contrast, aberrant, sustained T cell responses can persist over decades in human allergic disease. To understand these divergent outcomes, we employed bioinformatic, immunophenotyping and functional approaches with human diseased tissues, identifying an abundant population of type 2 helper T (TH2) cells with co-expression of TCF7 and LEF1, and features of chronic activation. These cells, which we termed TH2-multipotent progenitors (TH2-MPP) could self-renew and differentiate into cytokine-producing effector cells, regulatory T (Treg) cells and follicular helper T (TFH) cells. Single-cell T-cell-receptor lineage tracing confirmed lineage relationships between TH2-MPP, TH2 effectors, Treg cells and TFH cells. TH2-MPP persisted despite in vivo IL-4 receptor blockade, while thymic stromal lymphopoietin (TSLP) drove selective expansion of progenitor cells and rendered them insensitive to glucocorticoid-induced apoptosis in vitro. Together, our data identify TH2-MPP as an aberrant T cell population with the potential to sustain type 2 inflammation and support the paradigm that chronic T cell responses can be coordinated over time by progenitor cells.
Asunto(s)
Factor Nuclear 1-alfa del Hepatocito , Hipersensibilidad , Factor de Unión 1 al Potenciador Linfoide , Células Madre Multipotentes , Factor 1 de Transcripción de Linfocitos T , Células Th2 , Humanos , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Factor de Unión 1 al Potenciador Linfoide/genética , Células Th2/inmunología , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Factor Nuclear 1-alfa del Hepatocito/genética , Hipersensibilidad/inmunología , Células Madre Multipotentes/metabolismo , Células Madre Multipotentes/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Diferenciación Celular , Citocinas/metabolismo , Linfopoyetina del Estroma Tímico , Animales , Células Cultivadas , RatonesRESUMEN
There is pressing urgency to understand the pathogenesis of the severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2), which causes the disease COVID-19. SARS-CoV-2 spike (S) protein binds angiotensin-converting enzyme 2 (ACE2), and in concert with host proteases, principally transmembrane serine protease 2 (TMPRSS2), promotes cellular entry. The cell subsets targeted by SARS-CoV-2 in host tissues and the factors that regulate ACE2 expression remain unknown. Here, we leverage human, non-human primate, and mouse single-cell RNA-sequencing (scRNA-seq) datasets across health and disease to uncover putative targets of SARS-CoV-2 among tissue-resident cell subsets. We identify ACE2 and TMPRSS2 co-expressing cells within lung type II pneumocytes, ileal absorptive enterocytes, and nasal goblet secretory cells. Strikingly, we discovered that ACE2 is a human interferon-stimulated gene (ISG) in vitro using airway epithelial cells and extend our findings to in vivo viral infections. Our data suggest that SARS-CoV-2 could exploit species-specific interferon-driven upregulation of ACE2, a tissue-protective mediator during lung injury, to enhance infection.
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Células Epiteliales Alveolares/metabolismo , Enterocitos/metabolismo , Células Caliciformes/metabolismo , Interferón Tipo I/metabolismo , Mucosa Nasal/citología , Peptidil-Dipeptidasa A/genética , Adolescente , Células Epiteliales Alveolares/inmunología , Enzima Convertidora de Angiotensina 2 , Animales , Betacoronavirus/fisiología , COVID-19 , Línea Celular , Células Cultivadas , Niño , Infecciones por Coronavirus/virología , Enterocitos/inmunología , Células Caliciformes/inmunología , Infecciones por VIH/inmunología , Humanos , Gripe Humana/inmunología , Interferón Tipo I/inmunología , Pulmón/citología , Pulmón/patología , Macaca mulatta , Ratones , Mycobacterium tuberculosis , Mucosa Nasal/inmunología , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/virología , Receptores Virales/genética , SARS-CoV-2 , Serina Endopeptidasas/metabolismo , Análisis de la Célula Individual , Tuberculosis/inmunología , Regulación hacia ArribaRESUMEN
Severe asthma and sinus disease are consequences of type 2 inflammation (T2I), mediated by interleukin (IL)-33 signaling through its membrane-bound receptor, ST2. Soluble (s)ST2 reduces available IL-33 and limits T2I, but little is known about its regulation. We demonstrate that prostaglandin E2 (PGE2) drives production of sST2 to limit features of lung T2I. PGE2-deficient mice display diminished sST2. In humans with severe respiratory T2I, urinary PGE2 metabolites correlate with serum sST2. In mice, PGE2 enhanced sST2 secretion by mast cells (MCs). Mice lacking MCs, ST2 expression by MCs, or E prostanoid (EP)2 receptors by MCs showed reduced sST2 lung concentrations and strong T2I. Recombinant sST2 reduced T2I in mice lacking PGE2 or ST2 expression by MCs back to control levels. PGE2 deficiency also reversed the hyperinflammatory phenotype in mice lacking ST2 expression by MCs. PGE2 thus suppresses T2I through MC-derived sST2, explaining the severe T2I observed in low PGE2 states.
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Dinoprostona , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-33 , Pulmón , Mastocitos , Ratones Noqueados , Animales , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/genética , Mastocitos/inmunología , Mastocitos/metabolismo , Dinoprostona/metabolismo , Ratones , Interleucina-33/metabolismo , Humanos , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Asma/inmunología , Asma/metabolismo , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Ratones Endogámicos C57BL , Inflamación/inmunología , Femenino , Masculino , Transducción de Señal , Neumonía/inmunología , Neumonía/metabolismoRESUMEN
Mast cells are evolutionarily ancient sentinel cells. Like basophils, mast cells express the high-affinity receptor for immunoglobulin E (IgE) and have been linked to host defense and diverse immune-system-mediated diseases. To better characterize the function of these cells, we assessed the transcriptional profiles of mast cells isolated from peripheral connective tissues and basophils isolated from spleen and blood. We found that mast cells were transcriptionally distinct, clustering independently from all other profiled cells, and that mast cells demonstrated considerably greater heterogeneity across tissues than previously appreciated. We observed minimal homology between mast cells and basophils, which shared more overlap with other circulating granulocytes than with mast cells. The derivation of mast-cell and basophil transcriptional signatures underscores their differential capacities to detect environmental signals and influence the inflammatory milieu.
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Basófilos/fisiología , Células Sanguíneas/fisiología , Células del Tejido Conectivo/fisiología , Mastocitos/fisiología , Bazo/citología , Animales , Separación Celular , Células Cultivadas , Citometría de Flujo , Perfilación de la Expresión Génica , Inmunoglobulina E/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Análisis de Matrices TisularesRESUMEN
Multistep mast cell desensitization blocks the release of mediators following IgE crosslinking with increasing doses of Ag. Although its in vivo application has led to the safe reintroduction of drugs and foods in IgE-sensitized patients at risk for anaphylaxis, the mechanisms of the inhibitory process have remained elusive. We sought to investigate the kinetics, membrane, and cytoskeletal changes and to identify molecular targets. IgE-sensitized wild-type murine (WT) and FcεRIα humanized (h) bone marrow mast cells were activated and desensitized with DNP, nitrophenyl, dust mites, and peanut Ags. The movements of membrane receptors, FcεRI/IgE/Ag, actin, and tubulin and the phosphorylation of Syk, Lyn, P38-MAPK, and SHIP-1 were assessed. Silencing SHIP-1 protein was used to dissect the SHIP-1 role. Multistep IgE desensitization of WT and transgenic human bone marrow mast cells blocked the release of ß-hexosaminidase in an Ag-specific fashion and prevented actin and tubulin movements. Desensitization was regulated by the initial Ag dose, number of doses, and time between doses. FcεRI, IgE, Ags, and surface receptors were not internalized during desensitization. Phosphorylation of Syk, Lyn, p38 MAPK, and SHIP-1 increased in a dose-response manner during activation; in contrast, only SHIP-1 phosphorylation increased in early desensitization. SHIP-1 phosphatase function had no impact on desensitization, but silencing SHIP-1 increased ß-hexoxaminidase release, preventing desensitization. Multistep IgE mast cell desensitization is a dose- and time-regulated process that blocks ß-hexosaminidase, impacting membrane and cytoskeletal movements. Signal transduction is uncoupled, favoring early phosphorylation of SHIP-1. Silencing SHIP-1 impairs desensitization without implicating its phosphatase function.
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Actinas , Mastocitos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Animales , Humanos , Ratones , Inmunoglobulina E , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas/genética , Monoéster Fosfórico Hidrolasas , Receptores de IgE , Tubulina (Proteína)RESUMEN
BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) is a severe disease involving dysregulated type 2 inflammation. However, the role other inflammatory pathways play in AERD is poorly understood. OBJECTIVE: We sought to broadly define the inflammatory milieu of the upper respiratory tract in AERD and to determine the effects of IL-4Rα inhibition on mediators of nasal inflammation. METHODS: Twenty-two AERD patients treated with dupilumab for 3 months were followed over 3 visits and compared to 10 healthy controls. Nasal fluid was assessed for 45 cytokines and chemokines using Olink Target 48. Blood neutrophils and cultured human mast cells, monocytes/macrophages, and nasal fibroblasts were assessed for response to IL-4/13 stimulation in vitro. RESULTS: Of the nasal fluid cytokines measured, nearly one third were higher in AERD patients compared to healthy controls, including IL-6 and the IL-6 family-related cytokine oncostatin M (OSM), both of which correlated with nasal albumin levels, a marker of epithelial barrier dysregulation. Dupilumab significantly decreased many nasal mediators, including OSM and IL-6. IL-4 stimulation induced OSM production from mast cells and macrophages but not from neutrophils, and OSM and IL-13 stimulation induced IL-6 production from nasal fibroblasts. CONCLUSION: In addition to type 2 inflammation, innate and IL-6-related cytokines are also elevated in the respiratory tract in AERD. Both OSM and IL-6 are locally produced in nasal polyps and likely promote pathology by negatively affecting epithelial barrier function. IL-4Rα blockade, although seemingly directed at type 2 inflammation, also decreases mediators of innate inflammation and epithelial dysregulation, which may contribute to dupilumab's therapeutic efficacy in AERD.
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Anticuerpos Monoclonales Humanizados , Asma Inducida por Aspirina , Subunidad alfa del Receptor de Interleucina-4 , Interleucina-6 , Oncostatina M , Transducción de Señal , Humanos , Oncostatina M/metabolismo , Femenino , Masculino , Persona de Mediana Edad , Interleucina-6/metabolismo , Interleucina-6/inmunología , Adulto , Subunidad alfa del Receptor de Interleucina-4/metabolismo , Subunidad alfa del Receptor de Interleucina-4/inmunología , Asma Inducida por Aspirina/inmunología , Mastocitos/inmunología , Mastocitos/metabolismo , Células Cultivadas , Anciano , Fibroblastos/metabolismo , Fibroblastos/inmunología , Mucosa Nasal/inmunología , Mucosa Nasal/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismoRESUMEN
Macrophages expressing group V phospholipase A2 (Pla2g5) release the free fatty acid (FFA) linoleic acid (LA), potentiating lung type 2 inflammation. Although Pla2g5 and LA increase in viral infections, their role remains obscure. We generated Pla2g5flox/flox mice, deleted Pla2g5 by using the Cx3cr1cre transgene, and activated bone marrow-derived macrophages (BM-Macs) with poly:IC, a synthetic double-stranded RNA that triggers a viral-like immune response, known Pla2g5-dependent stimuli (IL-4, LPS + IFNγ, IL-33 + IL-4 + GM-CSF) and poly:IC + LA followed by lipidomic and transcriptomic analysis. Poly:IC-activated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs had downregulation of major bioactive lipids and critical enzymes producing those bioactive lipids. In addition, AKT phosphorylation was lower in poly:IC-stimulated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs, which was not restored by adding LA to poly:IC-stimulated BM-Macs. Consistently, Pla2g5flox/flox;Cx3cr1cre/+ mice had diminished poly:IC-induced lung inflammation, including inflammatory macrophage proliferation, while challenging Pla2g5flox/flox;Cx3cr1cre/+ mice with poly:IC + LA partially restored lung inflammation and inflammatory macrophage proliferation. Finally, mice lacking FFA receptor-1 (Ffar1)-null mice had reduced poly:IC-induced lung cell recruitment and tissue macrophage proliferation, not corrected by LA. Thus, Pla2g5 contributes to poly:IC-induced lung inflammation by regulating inflammatory macrophage proliferation and LA/Ffar1-mediated lung cell recruitment and tissue macrophage proliferation.
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Ácido Linoleico , Neumonía , Animales , Ratones , Proliferación Celular , Interleucina-4/metabolismo , Ácido Linoleico/metabolismo , Pulmón , MacrófagosRESUMEN
Barrier tissue dysfunction is a fundamental feature of chronic human inflammatory diseases1. Specialized subsets of epithelial cells-including secretory and ciliated cells-differentiate from basal stem cells to collectively protect the upper airway2-4. Allergic inflammation can develop from persistent activation5 of type 2 immunity6 in the upper airway, resulting in chronic rhinosinusitis, which ranges in severity from rhinitis to severe nasal polyps7. Basal cell hyperplasia is a hallmark of severe disease7-9, but it is not known how these progenitor cells2,10,11 contribute to clinical presentation and barrier tissue dysfunction in humans. Here we profile primary human surgical chronic rhinosinusitis samples (18,036 cells, n = 12) that span the disease spectrum using Seq-Well for massively parallel single-cell RNA sequencing12, report transcriptomes for human respiratory epithelial, immune and stromal cell types and subsets from a type 2 inflammatory disease, and map key mediators. By comparison with nasal scrapings (18,704 cells, n = 9), we define signatures of core, healthy, inflamed and polyp secretory cells. We reveal marked differences between the epithelial compartments of the non-polyp and polyp cellular ecosystems, identifying and validating a global reduction in cellular diversity of polyps characterized by basal cell hyperplasia, concomitant decreases in glandular cells, and phenotypic shifts in secretory cell antimicrobial expression. We detect an aberrant basal progenitor differentiation trajectory in polyps, and propose cell-intrinsic13, epigenetic14,15 and extrinsic factors11,16,17 that lock polyp basal cells into this uncommitted state. Finally, we functionally demonstrate that ex vivo cultured basal cells retain intrinsic memory of IL-4/IL-13 exposure, and test the potential for clinical blockade of the IL-4 receptor α-subunit to modify basal and secretory cell states in vivo. Overall, we find that reduced epithelial diversity stemming from functional shifts in basal cells is a key characteristic of type 2 immune-mediated barrier tissue dysfunction. Our results demonstrate that epithelial stem cells may contribute to the persistence of human disease by serving as repositories for allergic memories.
Asunto(s)
Hipersensibilidad/inmunología , Hipersensibilidad/patología , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/patología , Células Madre/inmunología , Células Madre/patología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Células Cultivadas , Epigénesis Genética , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Humanos , Hiperplasia/metabolismo , Hiperplasia/patología , Interleucina-13/inmunología , Interleucina-4/inmunología , Subunidad alfa del Receptor de Interleucina-4/antagonistas & inhibidores , Subunidad alfa del Receptor de Interleucina-4/inmunología , Persona de Mediana Edad , Pólipos Nasales/inmunología , Pólipos Nasales/patología , Rinitis/inmunología , Rinitis/patología , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Sinusitis/inmunología , Sinusitis/patología , Transcripción Genética , Transcriptoma , Adulto JovenRESUMEN
BACKGROUND: IgE-induced mast cell (MC) degranulation can be inhibited by IgG antibodies, signaling via FcγRIIb, but the effects of IgG on IgE-induced MC transcription are unknown. OBJECTIVE: We sought to assess inhibitory IgG:FcγRIIb effects on MC responses to IgE using complementary transcriptomic and functional approaches. METHODS: RNA sequencing was performed on bone marrow-derived MCs from wild-type and FcγRIIb-deficient mice to identify genes activated following IgE receptor crosslinking that were further modulated in the presence of antigen-specific IgG in an FcγRIIb-dependent fashion. Parallel analyses of signaling pathways and allergic responses in vivo were performed to assess the impact of these changes in gene expression. RESULTS: Rapid changes in the transcription of 879 genes occurred in MCs activated by IgE, peaking at 1 hour. Surprisingly, only 12% of these were altered by IgG signaling via FcγRIIb, including numerous transcripts involved in orchestrating type 2 responses linked to spleen tyrosine kinase signaling. Consistent with this finding, IgG suppressed IgE-induced phospho-intermediates in the spleen tyrosine kinase signaling pathway. In vivo studies confirmed that the IgG-mediated suppression of both systemic anaphylaxis and MC-driven tissue recruitment of inflammatory cells following allergen challenge was dependent on FcγRIIb. In contrast, genes in the STAT5a cell survival pathway were unaltered by IgG, and STAT5a phosphorylation increased after IgE-induced MC activation but was unaffected by IgG. CONCLUSIONS: Our findings indicate that inhibitory IgG:FcγRIIb signals block an IgE-induced proallergic program but spare a prosurvival program.
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Anafilaxia , Receptores de IgE , Ratones , Animales , Receptores de IgG , Quinasa Syk/metabolismo , Inmunoglobulina E , Mastocitos , Inmunoglobulina G , Degranulación de la CélulaRESUMEN
Aminoglycoside antibiotics, such as gentamicin and kanamycin, directly target the ribosome, yet the mechanisms by which these bactericidal drugs induce cell death are not fully understood. Recently, oxidative stress has been implicated as one of the mechanisms whereby bactericidal antibiotics kill bacteria. Here, we use systems-level approaches and phenotypic analyses to provide insight into the pathway whereby aminoglycosides ultimately trigger hydroxyl radical formation. We show, by disabling systems that facilitate membrane protein traffic, that mistranslation and misfolding of membrane proteins are central to aminoglycoside-induced oxidative stress and cell death. Signaling through the envelope stress-response two-component system is found to be a key player in this process, and the redox-responsive two-component system is shown to have an associated role. Additionally, we show that these two-component systems play a general role in bactericidal antibiotic-mediated oxidative stress and cell death, expanding our understanding of the common mechanism of killing induced by bactericidal antibiotics.
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Antibacterianos/farmacología , Membrana Celular/metabolismo , Proteínas de la Membrana/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , Aminoglicósidos/química , Escherichia coli/metabolismo , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Radical Hidroxilo , Modelos Biológicos , Modelos Genéticos , Oxidación-Reducción , Estrés Oxidativo , Desnaturalización Proteica , Pliegue de ProteínaRESUMEN
In this post-genomic era, our capacity to explore biological networks and predict network architectures has been greatly expanded, accelerating interest in systems biology. Here, we highlight recent systems biology studies in prokaryotes, consider the challenges ahead, and suggest opportunities for future studies in bacterial models.
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Bacterias/metabolismo , Biología de Sistemas , Bacterias/citología , Bacterias/genética , GenómicaRESUMEN
Mast cells (MCs) are widely recognized as central effector cells during type 2 inflammatory reactions and thought to also play a role in innate immune responses, wound healing, and potentially cancer. Circulating progenitor cells mature to MCs in peripheral tissues, where they exhibit phenotypic and functional heterogeneity. This diversity likely originates from differences in MC development imprinted by microenvironmental signals. The advent of single-cell transcriptomics reveals MC diversity beyond differences in proteases that were classically used to identify MC phenotypes. Here, we provide an overview of the current knowledge on MC progenitor differentiation and characteristics, and MC heterogeneity seen in health versus disease, that are drastically advanced through single-cell profiling technologies. This powerful approach can provide detailed cellular maps of tissues to decipher the complex cellular functions and interactions that may lead to identifying candidate factors to target in therapies.
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Hipersensibilidad , Transcriptoma , Diferenciación Celular , Humanos , Hipersensibilidad/metabolismo , Mastocitos/metabolismo , Péptido Hidrolasas/metabolismo , Células MadreRESUMEN
BACKGROUND: Mast cells (MCs) are pleiotropic cells that accumulate in the esophagus of patients with eosinophilic esophagitis (EoE) and are thought to contribute to disease pathogenesis, yet their properties and functions in this organ are largely unknown. OBJECTIVES: This study aimed to perform a comprehensive molecular and spatial characterization of esophageal MCs in EoE. METHODS: Esophageal biopsies obtained from patients with active EoE, patients with EoE in histologic remission, and individuals with histologically normal esophageal biopsies and no history of esophageal disease (ie, control individuals) were subject to single-cell RNA sequencing, flow cytometry, and immunofluorescence analyses. RESULTS: This study probed 39,562 single esophageal cells by single-cell RNA sequencing; approximately 5% of these cells were MCs. Dynamic MC expansion was identified across disease states. During homeostasis, TPSAB1highAREGhigh resident MCs were mainly detected in the lamina propria and exhibited a quiescent phenotype. In patients with active EoE, resident MCs assumed an activated phenotype, and 2 additional proinflammatory MC populations emerged in the intraepithelial compartment, each linked to a proliferating MKI67high cluster. One proinflammatory activated MC population, marked as KIThighIL1RL1highFCER1Alow, was not detected in disease remission (termed "transient MC"), whereas the other population, marked as CMA1highCTSGhigh, was detected in disease remission where it maintained an activated state (termed "persistent MC"). MCs were prominent producers of esophageal IL-13 mRNA and protein, a key therapeutic target in EoE. CONCLUSIONS: Esophageal MCs comprise heterogeneous populations with transcriptional signatures associated with distinct spatial compartmentalization and EoE disease status. In active EoE, they assume a proinflammatory state and locally proliferate, and they remain activated and poised to reinitiate inflammation even during disease remission.
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Esofagitis Eosinofílica , Proliferación Celular , Esofagitis Eosinofílica/genética , Esofagitis Eosinofílica/metabolismo , Humanos , Mastocitos/patología , Análisis de Secuencia de ARNRESUMEN
BACKGROUND: Eosinophilic asthma and nasal polyposis are hallmarks of aspirin-exacerbated respiratory disease (AERD), and IL-5 inhibition has been shown to provide therapeutic benefit. However, IL-5Rα is expressed on many cells in addition to eosinophils, and the mechanisms by which IL-5 inhibition leads to clinical benefit in eosinophilic asthma and nasal polyposis are unlikely to be due exclusively to antieosinophil effects. OBJECTIVE: We sought to identify the mechanisms by which anti-IL-5 treatment with mepolizumab improves respiratory inflammation in AERD. METHODS: The clinical characteristics, circulating granulocytes, nasal scraping transcripts, eosinophilic cationic protein, tryptase, and antibody levels, and urinary and nasal eicosanoid levels were measured for 18 subjects with AERD who were taking mepolizumab and compared with those of 18 matched subjects with AERD who were not taking mepolizumab. RESULTS: Subjects taking mepolizumab had significantly fewer peripheral blood eosinophils and basophils, and those cells that remained had higher surface CRTH2 expression than did the cells from subjects not taking mepolizumab. Nasal prostaglandin F2α, prostaglandin D2 metabolites, leukotriene B4, and thromboxane levels were lower in subjects taking mepolizumab, as were urinary levels of tetranor-prostaglandin D2 and leukotriene E4. The nasal epithelial cell transcripts that were overexpressed among subjects with AERD who were taking mepolizumab were enriched for genes involved in tight junction formation and cilium organization. Nasal and urinary prostaglandin E2, tryptase, and antibody levels were not different between the 2 groups. CONCLUSION: IL-5 inhibition in AERD decreases production of inflammatory eicosanoids and upregulates tight junction-associated nasal epithelial cell transcripts, likely due to decreased IL-5 signaling on tissue mast cells, eosinophils, and epithelial cells. These direct effects on multiple relevant immune cells contribute to the mechanism of benefit afforded by mepolizumab.
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Anticuerpos Monoclonales Humanizados/administración & dosificación , Asma Inducida por Aspirina , Basófilos , Eosinófilos , Pólipos Nasales , Adolescente , Adulto , Anciano , Asma Inducida por Aspirina/tratamiento farmacológico , Asma Inducida por Aspirina/inmunología , Asma Inducida por Aspirina/orina , Basófilos/inmunología , Basófilos/patología , Eicosanoides/inmunología , Eicosanoides/orina , Eosinófilos/inmunología , Eosinófilos/patología , Femenino , Humanos , Interleucina-5/inmunología , Subunidad alfa del Receptor de Interleucina-5/inmunología , Masculino , Persona de Mediana Edad , Pólipos Nasales/tratamiento farmacológico , Pólipos Nasales/inmunología , Pólipos Nasales/orinaRESUMEN
The American Initiative in Mast Cell Diseases (AIM) held its inaugural investigator conference at Stanford University School of Medicine in May 2019. The overarching goal of this meeting was to establish a Pan-American organization of physicians and scientists with multidisciplinary expertise in mast cell disease. To serve this unmet need, AIM envisions a network where basic, translational, and clinical researchers could establish collaborations with both academia and biopharma to support the development of new diagnostic methods, enhanced understanding of the biology of mast cells in human health and disease, and the testing of novel therapies. In these AIM proceedings, we highlight selected topics relevant to mast cell biology and provide updates regarding the recently described hereditary alpha-tryptasemia. In addition, we discuss the evaluation and treatment of mast cell activation (syndromes), allergy and anaphylaxis in mast cell disorders, and the clinical and biologic heterogeneity of the more indolent forms of mastocytosis. Because mast cell disorders are relatively rare, AIM hopes to achieve a coordination of scientific efforts not only in the Americas but also in Europe by collaborating with the well-established European Competence Network on Mastocytosis.
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Mastocitosis/diagnóstico , Mastocitosis/etiología , Mastocitosis/terapia , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Humanos , Mastocitosis/complicaciones , Investigación , Investigación Biomédica TraslacionalRESUMEN
BACKGROUND: The cause of severe nasal polyposis in aspirin-exacerbated respiratory disease (AERD) is unknown. Elevated antibody levels have been associated with disease severity in nasal polyps, but upstream drivers of local antibody production in nasal polyps are undetermined. OBJECTIVE: We sought to identify upstream drivers and phenotypic properties of local antibody-expressing cells in nasal polyps from subjects with AERD. METHODS: Sinus tissue was obtained from subjects with AERD, chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP), CRS without nasal polyps, and controls without CRS. Tissue antibody levels were quantified via ELISA and immunohistochemistry and were correlated with disease severity. Antibody-expressing cells were profiled with single-cell RNA sequencing, flow cytometry, and immunofluorescence, with IL-5Rα function determined through IL-5 stimulation and subsequent RNA sequencing and quantitative PCR. RESULTS: Tissue IgE and IgG4 levels were elevated in AERD compared with in controls (P < .01 for IgE and P < .001 for IgG4 vs CRSwNP). Subjects with AERD whose nasal polyps recurred rapidly had higher IgE levels than did subjects with AERD, with slower regrowth (P = .005). Single-cell RNA sequencing revealed increased IL5RA, IGHG4, and IGHE in antibody-expressing cells from patients with AERD compared with antibody-expressing cells from patients with CRSwNP. There were more IL-5Rα+ plasma cells in the polyp tissue from those with AERD than in polyp tissue from those with CRSwNP (P = .026). IL-5 stimulation of plasma cells in vitro induced changes in a distinct set of transcripts. CONCLUSIONS: Our study identifies an increase in antibody-expressing cells in AERD defined by transcript enrichment of IL5RA and IGHG4 or IGHE, with confirmed surface expression of IL-5Rα and functional IL-5 signaling. Tissue IgE and IgG4 levels are elevated in AERD, and higher IgE levels are associated with faster nasal polyp regrowth. Our findings suggest a role for IL-5Rα+ antibody-expressing cells in facilitating local antibody production and severe nasal polyps in AERD.
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Aspirina/efectos adversos , Inmunoglobulina E/metabolismo , Inmunoglobulina G/metabolismo , Subunidad alfa del Receptor de Interleucina-5/metabolismo , Pólipos Nasales/metabolismo , Sinusitis/metabolismo , Adulto , Anciano , Anticuerpos/metabolismo , Femenino , Humanos , Interleucina-5/metabolismo , Masculino , Persona de Mediana Edad , Pólipos Nasales/inducido químicamente , Células Plasmáticas/efectos de los fármacos , Células Plasmáticas/metabolismo , Análisis de Secuencia de ARN/métodos , Sinusitis/inducido químicamente , Adulto JovenRESUMEN
Macrophages have diverse functions in the pathogenesis, resolution, and repair of inflammatory processes. Elegant studies have elucidated the metabolomic and transcriptomic profiles of activated macrophages. However, the versatility of macrophage responses in inflammation is likely due, at least in part, to their ability to rearrange their repertoire of bioactive lipids, including fatty acids and oxylipins. This review will describe the fatty acids and oxylipins generated by macrophages and their role in type 1 and type 2 immune responses. We will highlight lipidomic studies that have shaped the current understanding of the role of lipids in macrophage polarization.
Asunto(s)
Ácidos Grasos/metabolismo , Activación de Macrófagos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Oxilipinas/metabolismo , Animales , Biomarcadores , Citocinas/metabolismo , Susceptibilidad a Enfermedades , Regulación de la Expresión Génica , Humanos , Inmunidad , Inflamación/etiología , Inflamación/metabolismo , Inflamación/patología , Mediadores de Inflamación , Metabolismo de los Lípidos , Lipidómica/métodos , Redes y Vías Metabólicas , Transducción de SeñalRESUMEN
Programmed cell death is a gene-directed process involved in the development and homeostasis of multicellular organisms. The most common mode of programmed cell death is apoptosis, which is characterized by a stereotypical set of biochemical and morphological hallmarks. Here we report that Escherichia coli also exhibit characteristic markers of apoptosis-including phosphatidylserine exposure, chromosome condensation, and DNA fragmentation-when faced with cell death-triggering stress, namely bactericidal antibiotic treatment. Notably, we also provide proteomic and genetic evidence for the ability of multifunctional RecA to bind peptide sequences that serve as substrates for eukaryotic caspases, and regulation of this phenotype by the protease, ClpXP, under conditions of cell death. Our findings illustrate that prokaryotic organisms possess mechanisms to dismantle and mark dying cells in response to diverse noxious stimuli and suggest that elaborate, multilayered proteolytic regulation of these features may have evolved in eukaryotes to harness and exploit their deadly potential.
Asunto(s)
Ampicilina/farmacología , Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Gentamicinas/farmacología , Norfloxacino/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Caspasas/metabolismo , Caspasas/fisiología , Cromosomas Bacterianos/efectos de los fármacos , Fragmentación del ADN , Endopeptidasa Clp/fisiología , Escherichia coli/citología , Escherichia coli/genética , Proteínas de Escherichia coli/fisiología , Etiquetado Corte-Fin in Situ , Fosfatidilserinas/análisis , Rec A Recombinasas/metabolismo , Rec A Recombinasas/fisiología , Respuesta SOS en Genética/efectos de los fármacos , Estrés Fisiológico , Especificidad por SustratoRESUMEN
The aim of this study was to assess if tactical and technical performance indicators (PIs) could be used in combination to model match outcomes in Australian Football (AF). A database of 101 technical PIs and 14 tactical PIs from every match in the 2009-2016 Australian Football League (AFL) seasons was merged. Two outcome measures Win-loss and Score margin were used as dependent variables. The top 45 ranked technical and tactical PIs from a feature selection process were used to model match outcome using decision tree and Generalised Linear Models (GLMs). Of the top 45 selected features, this included seven tactical PIs. The Win-loss-based Decision tree model achieved a classification accuracy of 89.0% and GLM 93.2%. A Score margin-based GLM achieved a root mean squared error (RMSE) of 6.9 points. A combined approach to the classification of match outcomes provided no improvement in model accuracy compared with previous literature. However, this study has established the relative importance of technical and tactical measures of performance in relation to successful team performance in AF.