RESUMEN
BACKGROUND: Group 2 innate lymphoid cells (ILC2s) are critical mediators of type 2 respiratory inflammation, releasing IL-5 and IL-13 and promoting the pulmonary eosinophilia associated with allergen provocation. Although ILC2s have been shown to promote eosinophil activities, the role of eosinophils in group 2 innate lymphoid cell (ILC2) responses is less well defined. OBJECTIVE: We sought to investigate the role of eosinophils in activation of ILC2s in models of allergic asthma and in vitro. METHODS: Inducible eosinophil-deficient mice were exposed to allergic respiratory inflammation models of asthma, such as ovalbumin or house dust mite challenge, or to innate models of type 2 airway inflammation, such as inhalation of IL-33. Eosinophil-specific IL-4/13-deficient mice were used to address the specific roles for eosinophil-derived cytokines. Direct cell interactions between ILC2s and eosinophils were assessed by in vitro culture experiments. RESULTS: Targeted depletion of eosinophils resulted in significant reductions of total and IL-5+ and IL-13+ lung ILC2s in all models of respiratory inflammation. This correlated with reductions in IL-13 levels and mucus in the airway. Eosinophil-derived IL-4/13 was necessary for both eosinophil and ILC2 accumulation in lung in allergen models. In vitro, eosinophils released soluble mediators that induced ILC2 proliferation and G protein-coupled receptor-dependent chemotaxis of ILC2s. Coculture of ILC2s and IL-33-activated eosinophils resulted in transcriptome changes in both ILC2s and eosinophils, suggesting potential novel reciprocal interactions. CONCLUSION: These studies demonstrate that eosinophils play a reciprocal role in ILC2 effector functions as part of both adaptive and innate type 2 pulmonary inflammatory events.
Asunto(s)
Asma , Inmunidad Innata , Ratones , Animales , Eosinófilos/metabolismo , Interleucina-33/metabolismo , Interleucina-13/metabolismo , Interleucina-5/metabolismo , Interleucina-4/metabolismo , Linfocitos , Pulmón , Citocinas/metabolismo , Asma/metabolismo , Inflamación/metabolismo , Alérgenos/metabolismoRESUMEN
BACKGROUND: There is a need for new and effective oral asthma therapies. Dexpramipexole, an oral eosinophil-lowering drug, has not previously been studied in asthma. OBJECTIVE: We sought to evaluate the safety and efficacy of dexpramipexole in lowering blood and airway eosinophilia in subjects with eosinophilic asthma. METHODS: We performed a randomized, double-blind, placebo-controlled proof-of-concept trial in adults with inadequately controlled moderate to severe asthma and blood absolute eosinophil count (AEC) greater than or equal to 300/µL. Subjects were randomly assigned (1:1:1:1) to dexpramipexole 37.5, 75, or 150 mg BID (twice-daily) or placebo. The primary end point was the relative change in AEC from baseline to week 12. Prebronchodilator FEV1 week-12 change from baseline was a key secondary end point. Nasal eosinophil peroxidase was an exploratory end point. RESULTS: A total of 103 subjects were randomly assigned to dexpramipexole 37.5 mg BID (N = 22), 75 mg BID (N = 26), 150 mg BID (N = 28), or placebo (N = 27). Dexpramipexole significantly reduced placebo-corrected AEC week-12 ratio to baseline, in both the 150-mg BID (ratio, 0.23; 95% CI, 0.12-0.43; P < .0001) and the 75-mg BID (ratio, 0.34; 95% CI, 0.18-0.65; P = .0014) dose groups, corresponding to 77% and 66% reductions, respectively. Dexpramipexole reduced the exploratory end point of nasal eosinophil peroxidase week-12 ratio to baseline in the 150-mg BID (median, 0.11; P = .020) and the 75-mg BID (median, 0.17; P = .021) groups. Placebo-corrected FEV1 increases were observed starting at week 4 (nonsignificant). Dexpramipexole displayed a favorable safety profile. CONCLUSIONS: Dexpramipexole demonstrated effective eosinophil lowering and was well tolerated. Additional larger clinical trials are needed to understand the clinical efficacy of dexpramipexole in asthma.
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Antiasmáticos , Asma , Eosinofilia Pulmonar , Adulto , Humanos , Pramipexol/farmacología , Pramipexol/uso terapéutico , Peroxidasa del Eosinófilo , Asma/tratamiento farmacológico , Eosinofilia Pulmonar/tratamiento farmacológico , Eosinófilos , Resultado del Tratamiento , Método Doble Ciego , Antiasmáticos/uso terapéuticoRESUMEN
Background: Pollen is a key source of aeroallergens responsible for allergic rhinitis, conjunctivitis, and asthma. Objective: The goal of this scoping review was to summarize current available literature on the factors that affect pollen counts, allergenicity, and thresholds that induce symptoms in individuals who were sensitized. Methods: Several databases showed no published articles with a similar scope as of January 2022. A search of these data bases yielded 373 articles for assessment. These were then reviewed for relevance, and articles were selected to demonstrate the breadth of available data on pollen counts, allergenicity, and thresholds that induce symptoms in individuals who were sensitized. Additional articles were identified through examination of bibliographies of search-identified articles. Results: Several environmental factors have shown a correlation with pollen counts and allergen load, including the distance from the source, wind characteristics, pollen size, terrain, urban environments, air composition (particulate matter, CO2 levels, ozone, NO2), and weather conditions (humidity, thunderstorms, precipitation). Pollen thresholds at which symptoms were induced varied by study, pollen type, symptom, disease, and location. In addition, there was heterogeneity in study designs, threshold definition, and outcome measures. Conclusion: This scoping review demonstrates the plethora of variables that influence the relationship between pollen and the symptoms of allergic diseases. Analysis of the available data sheds light on the complex interaction between environmental and biologic factors that affect pollen's role in allergic diseases and provides guidance on multiple areas for further investigation.
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Asma , Conjuntivitis , Rinitis Alérgica , Humanos , Alérgenos , PolenRESUMEN
OBJECTIVES: Eosinophilic esophagitis (EoE), a chronic food allergic disease, lacks sensitive and specific peripheral biomarkers. We hypothesized that levels of EoE-related biomarkers captured using a 1-hour minimally invasive Esophageal String Test (EST) would correlate with mucosal eosinophil counts and tissue concentrations of these same biomarkers. We aimed to determine whether a 1-hour EST accurately distinguishes active from inactive EoE or a normal esophagus. METHODS: In a prospective, multisite study, children and adults (ages 7-55 years) undergoing a clinically indicated esophagogastroduodenoscopy performed an EST with an esophageal dwell time of 1 hour. Subjects were divided into 3 groups: active EoE, inactive EoE, and normal esophageal mucosa. Eosinophil-associated protein levels were compared between EST effluents and esophageal biopsy extracts. Statistical modeling was performed to select biomarkers that best correlated with and predicted eosinophilic inflammation. RESULTS: One hundred thirty-four subjects (74 children, 60 adults) with active EoE (n = 62), inactive EoE (n = 37), and patient controls with a normal esophagus (n = 35) completed the study. EST-captured eosinophil-associated biomarkers correlated significantly with peak eosinophils/high-power field, endoscopic visual scoring, and the same proteins extracted from mucosal biopsies. Statistical modeling, using combined eotaxin-3 and major basic protein-1 concentrations, led to the development of EoE scores that distinguished subjects with active EoE from inactive EoE or normal esophagi. Eighty-seven percent of children, 95% of parents, and 92% of adults preferred the EST over endoscopy if it provided similar information. DISCUSSION: The 1-hour EST accurately distinguishes active from inactive EoE in children and adults and may facilitate monitoring of disease activity in a safe and minimally invasive fashion.
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Esofagitis Eosinofílica/diagnóstico , Eosinófilos , Mucosa Esofágica/citología , Esófago/citología , Adolescente , Adulto , Biomarcadores/análisis , Biomarcadores/metabolismo , Biopsia , Quimiocina CCL24/análisis , Quimiocina CCL24/metabolismo , Quimiocina CCL26/análisis , Quimiocina CCL26/metabolismo , Niño , Endoscopía del Sistema Digestivo , Esofagitis Eosinofílica/patología , Mucosa Esofágica/diagnóstico por imagen , Mucosa Esofágica/patología , Esófago/diagnóstico por imagen , Esófago/patología , Estudios de Factibilidad , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto JovenRESUMEN
The inflammatory responses in chronic airway diseases leading to emphysema are not fully defined. We hypothesised that lung eosinophilia contributes to airspace enlargement in a mouse model and to emphysema in patients with chronic obstructive pulmonary disease (COPD).A transgenic mouse model of chronic type 2 pulmonary inflammation (I5/hE2) was used to examine eosinophil-dependent mechanisms leading to airspace enlargement. Human sputum samples were collected for translational studies examining eosinophilia and matrix metalloprotease (MMP)-12 levels in patients with chronic airways disease.Airspace enlargement was identified in I5/hE2 mice and was dependent on eosinophils. Examination of I5/hE2 bronchoalveolar lavage identified elevated MMP-12, a mediator of emphysema. We showed, in vitro, that eosinophil-derived interleukin (IL)-13 promoted alveolar macrophage MMP-12 production. Airspace enlargement in I5/hE2 mice was dependent on MMP-12 and eosinophil-derived IL-4/13. Consistent with this, MMP-12 was elevated in patients with sputum eosinophilia and computed tomography evidence of emphysema, and also negatively correlated with forced expiratory volume in 1â s.A mouse model of chronic type 2 pulmonary inflammation exhibited airspace enlargement dependent on MMP-12 and eosinophil-derived IL-4/13. In chronic airways disease patients, lung eosinophilia was associated with elevated MMP-12 levels, which was a predictor of emphysema. These findings suggest an underappreciated mechanism by which eosinophils contribute to the pathologies associated with asthma and COPD.
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Eosinófilos/inmunología , Interleucina-13/inmunología , Neumonía/etiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfisema Pulmonar/etiología , Anciano , Animales , Asma/inmunología , Asma/patología , Modelos Animales de Enfermedad , Eosinófilos/patología , Femenino , Humanos , Interleucina-4/inmunología , Macrófagos Alveolares/patología , Masculino , Metaloproteinasa 12 de la Matriz/inmunología , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Análisis Multivariante , Neumonía/inmunología , Neumonía/patología , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Enfermedad Pulmonar Obstructiva Crónica/patología , Enfisema Pulmonar/inmunología , Enfisema Pulmonar/patología , Análisis de Regresión , Sistema Respiratorio/fisiopatologíaRESUMEN
BACKGROUND: The persistence of eosinophils in sputum despite high doses of corticosteroids indicates disease severity in asthmatic patients. Chronic inflamed airways can lose tolerance over time to immunogenic entities released on frequent eosinophil degranulation, which further contributes to disease severity and necessitates an increase in maintenance corticosteroids. OBJECTIVES: We sought to investigate the possibility of a polyclonal autoimmune event in the airways of asthmatic patients and to identify associated clinical and molecular characteristics. METHODS: The presence of autoantibodies against eosinophil peroxidase (EPX) and anti-nuclear antibodies was investigated in patients with eosinophilic asthma maintained on high-dose corticosteroids, prednisone, or both. The ability of sputum immunoglobulins to induce eosinophil degranulation in vitro was assessed. In addition, the associated inflammatory microenvironment in patients with detectable autoantibodies was examined. RESULTS: We report a "polyclonal" autoimmune event occurring in the airways of prednisone-dependent asthmatic patients with increased eosinophil activity, recurrent pulmonary infections, or both, as evident by the concomitant presence of sputum anti-EPX and anti-nuclear antibodies of the IgG subtype. Extensive cytokine profiling of sputum revealed a TH2-dominated microenvironment (eotaxin-2, IL-5, IL-18, and IL-13) and increased signalling molecules that support the formation of ectopic lymphoid structures (B-cell activating factor and B cell-attracting chemokine 1). Immunoprecipitated sputum immunoglobulins from patients with increased autoantibody levels triggered eosinophil degranulation in vitro, with release of extensive histone-rich extracellular traps, an event unsuppressed by dexamethasone and possibly contributing to the steroid-unresponsive nature of these eosinophilic patients. CONCLUSION: This study identifies an autoimmune endotype of severe asthma that can be identified by the presence of sputum autoantibodies against EPX and autologous cellular components.
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Asma/inmunología , Autoanticuerpos/metabolismo , Eosinofilia Pulmonar/inmunología , Esputo/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Antiasmáticos/uso terapéutico , Anticuerpos Antinucleares/metabolismo , Asma/tratamiento farmacológico , Biomarcadores/metabolismo , Peroxidasa del Eosinófilo/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prednisona/uso terapéutico , Eosinofilia Pulmonar/tratamiento farmacológico , Estudios Retrospectivos , Índice de Severidad de la EnfermedadRESUMEN
RATIONALE: The release of eosinophil granule proteins in the lungs of patients with asthma has been dogmatically linked with lung remodeling and airway hyperresponsiveness. However, the demonstrated inability of established mouse models to display the eosinophil degranulation occurring in human subjects has prevented a definitive in vivo test of this hypothesis. OBJECTIVES: To demonstrate in vivo causative links between induced pulmonary histopathologies/lung dysfunction and eosinophil degranulation. METHODS: A transgenic mouse model of chronic T-helper cell type 2-driven inflammation overexpressing IL-5 from T cells and human eotaxin 2 in the lung (I5/hE2) was used to test the hypothesis that chronic histopathologies and the development of airway hyperresponsiveness occur as a consequence of extensive eosinophil degranulation in the lung parenchyma. MEASUREMENT AND MAIN RESULTS: Studies targeting specific inflammatory pathways in I5/hE2 mice surprisingly showed that eosinophil-dependent immunoregulative events and not the release of individual secondary granule proteins are the central contributors to T-helper cell type 2-induced pulmonary remodeling and lung dysfunction. Specifically, our studies highlighted a significant role for eosinophil-dependent IL-13 expression. In contrast, extensive degranulation leading to the release of major basic protein-1 or eosinophil peroxidase was not causatively linked to many of the induced pulmonary histopathologies. However, these studies did define a previously unappreciated link between the release of eosinophil peroxidase (but not major basic protein-1) and observed levels of induced airway mucin. CONCLUSIONS: These data suggest that improvements observed in patients with asthma responding to therapeutic strategies ablating eosinophils may occur as a consequence of targeting immunoregulatory mechanisms and not by simply eliminating the destructive activities of these purportedly end-stage effector cells.
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Eosinófilos/metabolismo , Inflamación/metabolismo , Inflamación/patología , Pulmón/metabolismo , Pulmón/patología , Animales , Quimiocina CCL24/metabolismo , Enfermedad Crónica , Modelos Animales de Enfermedad , Citometría de Flujo , Interleucina-5/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Células Th2/metabolismoRESUMEN
Eosinophils are recruited to the airways as a prominent feature of the asthmatic inflammatory response where they are broadly perceived as promoting pathophysiology. Respiratory virus infections exacerbate established asthma; however, the role of eosinophils and the nature of their interactions with respiratory viruses remain uncertain. To explore these questions, we established acute infection with the rodent pneumovirus, pneumonia virus of mice (PVM), in 3 distinct mouse models of Th2 cytokine-driven asthmatic inflammation. We found that eosinophils recruited to the airways of otherwise naïve mice in response to Aspergillus fumigatus, but not ovalbumin sensitization and challenge, are activated by and degranulate specifically in response to PVM infection. Furthermore, we demonstrate that activated eosinophils from both Aspergillus antigen and cytokine-driven asthma models are profoundly antiviral and promote survival in response to an otherwise lethal PVM infection. Thus, although activated eosinophils within a Th2-polarized inflammatory response may have pathophysiologic features, they are also efficient and effective mediators of antiviral host defense.
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Eosinófilos/inmunología , Pulmón/inmunología , Pulmón/virología , Virus de la Neumonía Murina/inmunología , Infecciones por Pneumovirus/inmunología , Animales , Aspergillus fumigatus/inmunología , Asma/inmunología , Asma/microbiología , Degranulación de la Célula , Eosinófilos/fisiología , Eosinófilos/virología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ovalbúmina/inmunologíaRESUMEN
BACKGROUND: Contact toxicant reactions are accompanied by localized skin inflammation and concomitant increases in site-specific itch responses. The role(s) of eosinophils in these reactions is poorly understood. However, previous studies have suggested that localized eosinophil-nerve interactions at sites of inflammation significantly alter tissue innervation. OBJECTIVE: To define a potential mechanistic link between eosinophils and neurosensory responses in the skin leading to itching. METHODS: BALB/cJ mice were exposed to different contact toxicants, identifying trimellitic anhydride (TMA) for further study on the basis of inducing a robust eosinophilia accompanied by degranulation. Subsequent studies using TMA were performed with wild type versus eosinophil-deficient PHIL mice, assessing edematous responses and remodeling events such as sensory nerve innervation of the skin and induced pathophysiological responses (ie, itching). RESULTS: Exposure to TMA, but not dinitrofluorobenzene, resulted in a robust eosinophil skin infiltrate accompanied by significant levels of degranulation. Follow-up studies using TMA with wild type versus eosinophil-deficient PHIL mice showed that the induced edematous responses and histopathology were, in part, causatively linked with the presence of eosinophils. Significantly, these data also demonstrated that eosinophil-mediated events correlated with a significant increase in substance P content of the cutaneous nerves and an accompanying increase in itching, both of which were abolished in the absence of eosinophils. CONCLUSIONS: Eosinophil-mediated events following TMA contact toxicant reactions increase skin sensory nerve substance P and, in turn, increase itching responses. Thus, eosinophil-nerve interactions provide a potential mechanistic link between eosinophil-mediated events and neurosensory responses following exposure to some contact toxicants.
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Eosinófilos/inmunología , Prurito/etiología , Piel/inmunología , Piel/inervación , Alérgenos/administración & dosificación , Alérgenos/inmunología , Animales , Degranulación de la Célula , Colágeno/metabolismo , Dinitrofluorobenceno/administración & dosificación , Dinitrofluorobenceno/efectos adversos , Modelos Animales de Enfermedad , Eosinofilia/inmunología , Eosinofilia/metabolismo , Eosinofilia/patología , Eosinófilos/metabolismo , Fibrosis , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Ratones , Anhídridos Ftálicos/administración & dosificación , Anhídridos Ftálicos/efectos adversos , Anhídridos Ftálicos/inmunología , Prurito/diagnóstico , Piel/efectos de los fármacos , Piel/patología , Sustancia P/genética , Sustancia P/metabolismoRESUMEN
Eosinophil activities are often linked with allergic diseases such as asthma and the pathologies accompanying helminth infection. These activities have been hypothesized to be mediated, in part, by the release of cationic proteins stored in the secondary granules of these granulocytes. The majority of the proteins stored in these secondary granules (by mass) are major basic protein 1 (MBP-1) and eosinophil peroxidase (EPX). Unpredictably, a knockout approach targeting the genes encoding these proteins demonstrated that, unlike in mice containing a single deficiency of only MBP-1 or EPX, the absence of both granule proteins resulted in the near complete loss of peripheral blood eosinophils with no apparent impact on any other hematopoietic lineage. Moreover, the absence of MBP-1 and EPX promoted a concomitant loss of eosinophil lineage-committed progenitors in the marrow, identifying a specific blockade in eosinophilopoiesis as the causative event. Significantly, this blockade of eosinophilopoiesis is also observed in ex vivo cultures of marrow progenitors and is not rescued in vivo by adoptive bone marrow engraftment, suggesting a cell-autonomous defect in marrow progenitors. These observations implicate a role for granule protein gene expression as a regulator of eosinophilopoiesis and provide another strain of mice congenitally deficient of eosinophils.
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Proteína Mayor Básica del Eosinófilo/fisiología , Peroxidasa del Eosinófilo/fisiología , Eosinófilos/fisiología , Mielopoyesis/genética , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/fisiología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Proteína Mayor Básica del Eosinófilo/genética , Proteína Mayor Básica del Eosinófilo/metabolismo , Peroxidasa del Eosinófilo/genética , Peroxidasa del Eosinófilo/metabolismo , Eosinófilos/efectos de los fármacos , Eosinófilos/metabolismo , Interleucina-5/farmacología , Recuento de Leucocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mielopoyesis/efectos de los fármacos , Mielopoyesis/fisiologíaAsunto(s)
Peroxidasa del Eosinófilo/metabolismo , Factor de Transcripción GATA3/metabolismo , Rinitis/metabolismo , Sinusitis/metabolismo , Proteínas de Dominio T Box/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Enfermedad Crónica , Senos Etmoidales/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , FenotipoAsunto(s)
Esofagitis Eosinofílica/metabolismo , Factor de Transcripción GATA3/metabolismo , Reflujo Gastroesofágico/metabolismo , Estudios de Casos y Controles , Niño , Preescolar , Esofagitis Eosinofílica/tratamiento farmacológico , Femenino , Reflujo Gastroesofágico/tratamiento farmacológico , Humanos , Masculino , Inhibidores de la Bomba de Protones/uso terapéutico , ARN Mensajero/metabolismo , Estudios Retrospectivos , Células Th2/efectos de los fármacos , Células Th2/metabolismoRESUMEN
OBJECTIVE: Eosinophil predominant inflammation characterises histological features of eosinophilic oesophagitis (EoE). Endoscopy with biopsy is currently the only method to assess oesophageal mucosal inflammation in EoE. We hypothesised that measurements of luminal eosinophil-derived proteins would correlate with oesophageal mucosal inflammation in children with EoE. DESIGN: The Enterotest diagnostic device was used to develop an oesophageal string test (EST) as a minimally invasive clinical device. EST samples and oesophageal mucosal biopsies were obtained from children undergoing upper endoscopy for clinically defined indications. Eosinophil-derived proteins including eosinophil secondary granule proteins (major basic protein-1, eosinophil-derived neurotoxin, eosinophil cationic protein, eosinophil peroxidase) and Charcot-Leyden crystal protein/galectin-10 were measured by ELISA in luminal effluents eluted from ESTs and extracts of mucosal biopsies. RESULTS: ESTs were performed in 41 children with active EoE (n=14), EoE in remission (n=8), gastro-oesophageal reflux disease (n=4) and controls with normal oesophagus (n=15). EST measurement of eosinophil-derived protein biomarkers significantly distinguished between children with active EoE, treated EoE in remission, gastro-oesophageal reflux disease and normal oesophagus. Levels of luminal eosinophil-derived proteins in EST samples significantly correlated with peak and mean oesophageal eosinophils/high power field (HPF), eosinophil peroxidase indices and levels of the same eosinophil-derived proteins in extracts of oesophageal biopsies. CONCLUSIONS: The presence of eosinophil-derived proteins in luminal secretions is reflective of mucosal inflammation in children with EoE. The EST is a novel, minimally invasive device for measuring oesophageal eosinophilic inflammation in children with EoE.
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Esofagitis Eosinofílica/diagnóstico , Esófago/metabolismo , Mucositis/diagnóstico , Adolescente , Biomarcadores/metabolismo , Biopsia , Niño , Diagnóstico Diferencial , Proteínas en los Gránulos del Eosinófilo/metabolismo , Esofagitis Eosinofílica/metabolismo , Esofagitis Eosinofílica/terapia , Esófago/patología , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/metabolismo , Glicoproteínas/metabolismo , Humanos , Lisofosfolipasa/metabolismo , Mucositis/metabolismo , Mucositis/terapia , Membrana Mucosa/patología , Sensibilidad y Especificidad , Manejo de Especímenes/instrumentación , Manejo de Especímenes/métodos , Adulto JovenRESUMEN
OBJECTIVE: To evaluate eosinophil peroxidase (EPX) as a biomarker for tissue levels of eosinophilia, cytokines, and chemokines within chronic rhinosinusitis (CRS). METHODS: Twenty-eight subjects undergoing sinonasal surgery were prospectively enrolled. Ethmoid tissue was analyzed with an in-house EPX immunoassay and a 48-plex cytokine-chemokine array. Clinical severity was assessed using SNOT-22 and Lund-Mackay scores. Subjects were grouped as follows: controls, polyp status (CRS with [CRSwNP] and without nasal polyps [CRSsNP]), tissue eosinophilia (eosinophilic CRS [eCRS], non-eosinophilic CRS [neCRS]), or combinations thereof (eCRSwNP, eCRSsNP, neCRSsNP). eCRS was defined as >10 eosinophils per high power field (HPF). Subjects without CRS or asthma were enrolled as controls. RESULTS: EPX was elevated in CRSwNP compared to control (p = 0.007), in eCRS compared to neCRS (p = 0.002), and in eCRSwNP along with eCRSsNP compared to neCRSsNP (p = 0.023, p = 0.015, respectively). eCRS displayed elevated IL-5 compared to neCRS (p = 0.005). No significant differences in EPX or IL-5 were observed between eCRSwNP and eCRSsNP. IL-5 was elevated in eCRSwNP (p = 0.019) compared neCRSsNP. Area under the receiver operator characteristic curve was 0.938 (95% CI, 0.835-1.00) for EPX and tissue eosinophilia, with an optimal cut-point of 470 ng/mL being 100% specific and 81.25% sensitive for tissue eosinophilia. Linear regression revealed a strong correlation between EPX and IL-5 (R2 = 0.64, p < 0.001). Comparing EPX and IL-5, only EPX displayed significant correlation with SNOT-22 (p = 0.04) and Lund-Mackay score (p = 0.004). CONCLUSION: EPX is associated with tissue eosinophilia in CRS patients regardless of polyp status. EPX correlates with IL-5 and could be potentially considered a biomarker for anti-IL-5 therapies. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:69-78, 2024.
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Eosinofilia , Pólipos Nasales , Rinitis , Rinosinusitis , Sinusitis , Humanos , Biomarcadores , Enfermedad Crónica , Citocinas , Peroxidasa del Eosinófilo , Eosinofilia/complicaciones , Eosinófilos , Interleucina-5 , Pólipos Nasales/complicaciones , Pólipos Nasales/diagnóstico , Rinitis/complicaciones , Rinitis/diagnóstico , Sinusitis/complicaciones , Sinusitis/diagnóstico , Sinusitis/cirugíaRESUMEN
Leukotrienes (i.e., products of the 5-lipoxygenase pathway) are thought to be contributors to lung pathologies. Moreover, eosinophils have been linked with pulmonary leukotriene activities both as potential sources of these mediators and as responding effector cells. The objective of the present study was to define the role(s) of leukotrienes in the lung pathologies accompanying eosinophil-associated chronic respiratory inflammation. A transgenic mouse model of chronic T helper (Th) 2-driven inflammation expressing IL-5 from T cells and human eotaxin-2 locally in the lung (I5/hE2) was used to define potential in vivo relationships among eosinophils, leukotrienes, and chronic Th2-polarized pulmonary inflammation. Airway levels of cys-leukotrienes and leukotriene B4 (LTB4) are both significantly elevated in I5/hE2 mice. The eosinophil-mediated airway hyperresponsiveness (AHR) characteristic of these mice was abolished in the absence of leukotrienes (i.e., 5-lipoxygenase-deficient I5/hE2). More importantly, the loss of leukotrienes led to an unexpectedly significant decrease in collagen deposition (i.e., pulmonary fibrosis) that accompanied elevated levels of IL-4/-13 and TGF-ß in the lungs of I5/hE2 mice. Further studies using mice deficient for the LTB4 receptor (BLT-1(-/-)/I5/hE2) and I5/hE2 animals administered a cys-leukotriene receptor antagonist (montelukast) demonstrated that the AHR and the enhanced pulmonary fibrosis characteristic of the I5/hE2 model were uniquely cys-leukotriene-mediated events. These data demonstrate that, similar to allergen challenge models of wild-type mice, cys-leukotrienes underlie AHR in this transgenic model of severe pulmonary Th2 inflammation. These data also suggest that an underappreciated link exists among eosinophils, cys-leukotriene-mediated events, and fibrotic remodeling associated with elevated levels of IL-4/-13 and TGF-ß.
Asunto(s)
Eosinófilos/inmunología , Leucotrienos/inmunología , Neumonía/etiología , Fibrosis Pulmonar/etiología , Animales , Araquidonato 5-Lipooxigenasa/deficiencia , Araquidonato 5-Lipooxigenasa/genética , Araquidonato 5-Lipooxigenasa/inmunología , Hiperreactividad Bronquial/inmunología , Quimiocina CCL24/genética , Quimiocina CCL24/inmunología , Modelos Animales de Enfermedad , Eosinófilos/patología , Humanos , Interleucina-5/inmunología , Leucotrieno B4/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Neumonía/inmunología , Neumonía/patología , Fibrosis Pulmonar/inmunología , Fibrosis Pulmonar/patología , Receptores de Leucotrieno B4/deficiencia , Receptores de Leucotrieno B4/genética , Receptores de Leucotrieno B4/inmunología , Células Th2/inmunología , Células Th2/patologíaRESUMEN
The respective life histories of human subjects and mice are well defined and describe a unique story of evolutionary conservation extending from sequence identity within the genome to the underpinnings of biochemical, cellular, and physiologic pathways. As a consequence, the hematopoietic lineages of both species are invariantly maintained, each with identifiable eosinophils. This canonical presence nonetheless does not preclude disparities between human and mouse eosinophils, their effector functions, or both. Indeed, many books and reviews dogmatically highlight differences, providing a rationale to discount the use of mouse models of human eosinophilic diseases. We suggest that this perspective is parochial and ignores the wealth of available studies and the consensus of the literature that overwhelming similarities (and not differences) exist between human and mouse eosinophils. The goal of this review is to summarize this literature and in some cases provide experimental details comparing and contrasting eosinophils and eosinophil effector functions in human subjects versus mice. In particular, our review will provide a summation and an easy-to-use reference guide to important studies demonstrating that although differences exist, more often than not, their consequences are unknown and do not necessarily reflect inherent disparities in eosinophil function but instead species-specific variations. The conclusion from this overview is that despite nominal differences, the vast similarities between human and mouse eosinophils provide important insights as to their roles in health and disease and, in turn, demonstrate the unique utility of mouse-based studies with an expectation of valid extrapolation to the understanding and treatment of patients.
Asunto(s)
Eosinófilos/fisiología , Animales , Degranulación de la Célula , Proteína Catiónica del Eosinófilo/fisiología , Peroxidasa del Eosinófilo/fisiología , Evolución Molecular , Glicoproteínas/fisiología , Hematopoyesis , Humanos , Lisofosfolipasa/fisiología , RatonesRESUMEN
This case reports the unique association of eosinophilic gastrointestinal disease with eosinophilic bronchitis, asthma and chronic rhinosinusitis and some features of lymphocytic hypereosinophilic syndrome, describes a diagnostic protocol for patients with asthma and persistent eosinophilic bronchitis, and suggests that the use of a novel EPX-mAb provides a reliable method to identify eosinophilic inflammation.
RESUMEN
The analysis of eosinophil shape change and mediator secretion is a useful tool in understanding how eosinophils respond to immunological stimuli and chemotactic factors. Eosinophils undergo dramatic shape changes, along with secretion of the granule-derived enzyme eosinophil peroxidase (EPX) in response to chemotactic stimuli including platelet-activating factor (PAF) and CCL11 (eotaxin-1). Here, we describe the analysis of eosinophil shape change by confocal microscopy analysis and provide an experimental approach for comparing unstimulated cells with those that have been stimulated to undergo chemotaxis. In addition, we illustrate two different degranulation assays for EPX using OPD and an ELISA technique and show how eosinophil degranulation may be assessed from in vitro as well as ex vivo stimulation.
Asunto(s)
Eosinófilos/metabolismo , Eosinófilos/fisiología , Microscopía Fluorescente/métodos , Secreciones Corporales , Degranulación de la Célula/inmunología , Forma de la Célula/fisiología , Quimiocina CCL11 , Quimiotaxis , Ensayo de Inmunoadsorción Enzimática/métodos , Peroxidasa del Eosinófilo/inmunología , Humanos , Leucocitos , Neutrófilos/inmunología , Factor de Activación Plaquetaria , Vías Secretoras/fisiologíaRESUMEN
BACKGROUND & AIMS: Eosinophilic esophagitis (EoE) is characterized by medically/surgically-resistant gastroesophageal reflux symptoms and dense squamous eosinophilia. Studies suggest that histologic assessment of esophageal eosinophilia alone cannot reliably separate patients with EoE from those with gastroesophageal reflux disease (GERD). Our goal was to develop an assay to identify EoE patients and perhaps differentiate EoE from other causes of esophageal eosinophilia. METHODS: A monoclonal antibody specific for an eosinophil secondary granule protein (eosinophil peroxidase [EPX]) was developed and shown to specifically identify intact eosinophils and detect eosinophil degranulation in formalin-fixed specimens. A histopathologic scoring algorithm was developed to analyze data from patient evaluations; the utility of this algorithm was assessed by using archived esophageal tissues from patients with known diagnoses of EoE and GERD as well as controls from 2 tertiary care centers. RESULTS: Intraobserver/interobserver blinded evaluations demonstrated a significant difference (P < .001) between scores of samples taken from control subjects, from patients with esophageal eosinophilia who had a diagnosis of EoE, and from patients with GERD (P < .001). This algorithm also was able to identify patients whose clinical course was suggestive of a diagnosis of EoE, but that nonetheless failed to reach the critical threshold number of > or =15 eosinophils in a high-power (40x) microscopy field. CONCLUSIONS: A novel immunohistochemical scoring system was developed to address an unmet medical need to differentiate histologic specimens from patients with EoE relative to those with GERD. The availability of a unique anti-EPX-specific monoclonal antibody, combined with the ease/rapidity of this staining method and scoring system, will provide a valuable strategy for the assessment of esophageal eosinophilia.