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Axion dark matter experiment ultra-low noise haloscope technology has enabled the successful completion of two science runs (1A and 1B) that looked for dark matter axions in the 2.66-3.1 µeV mass range with Dine-Fischler-Srednicki-Zhitnisky sensitivity [Du et al., Phys. Rev. Lett. 120, 151301 (2018) and Braine et al., Phys. Rev. Lett. 124, 101303 (2020)]. Therefore, it is the most sensitive axion search experiment to date in this mass range. We discuss the technological advances made in the last several years to achieve this sensitivity, which includes the implementation of components, such as the state-of-the-art quantum-noise-limited amplifiers and a dilution refrigerator. Furthermore, we demonstrate the use of a frequency tunable microstrip superconducting quantum interference device amplifier in run 1A, and a Josephson parametric amplifier in run 1B, along with novel analysis tools that characterize the system noise temperature.
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Asma , Rinitis Alérgica , Algoritmos , Humanos , Rinitis Alérgica/tratamiento farmacológicoRESUMEN
BACKGROUND: Immunotherapy with peptide hydrolysates from Lolium perenne (LPP) is an alternative treatment for seasonal allergic rhinitis with or without asthma. The aim of this study was to assess the clinical efficacy and safety of a cumulative dose of 170 µg LPP administered subcutaneously over 3 weeks. METHODS: In a randomized, double-blind, placebo-controlled trial, 554 adults with grass pollen rhinoconjunctivitis were randomized (1:2 ratio) to receive 8 subcutaneous injections of placebo or 170 µg LPP administered in increasing doses in 4 visits over 3 weeks. The primary outcome was the combined symptom and medication score (CSMS) measured over the peak pollen season. Reactivity to conjunctival provocation test (CPT) and quality of life (QOL) was assessed as secondary endpoints. RESULTS: The mean reduction in CSMS in the LPP vs placebo group was -15.5% (P = .041) during the peak period and -17.9% (P = .029) over the entire pollen season. LPP-treated group had a reduced reactivity to CPT (P < .001) and, during the pollen season, a lower rhinoconjunctivitis QOL global score (P = .005) compared with placebo group. Mostly mild and WAO grade 1 early systemic reaction (ESR) were observed ≤30 minutes in 10.5% of LPP-treated patients, whereas 3 patients with a medical history of asthma (<1%) experienced a serious ESR that resolved with rescue medication. CONCLUSION: Lolium perenne pollen peptides administered over 3 weeks before the grass pollen season significantly reduced seasonal symptoms and was generally safe and well-tolerated.
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Alérgenos/inmunología , Asma/inmunología , Asma/terapia , Desensibilización Inmunológica , Péptidos/inmunología , Poaceae/efectos adversos , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/terapia , Alérgenos/administración & dosificación , Asma/complicaciones , Estudios de Casos y Controles , Desensibilización Inmunológica/efectos adversos , Desensibilización Inmunológica/métodos , Esquema de Medicación , Femenino , Humanos , Masculino , Péptidos/administración & dosificación , Polen/inmunología , Calidad de Vida , Rinitis Alérgica Estacional/complicaciones , Estaciones del Año , Resultado del TratamientoRESUMEN
BACKGROUND: Systemic allergic reactions are a risk for allergen immunotherapy that utilizes intact allergen preparations. We evaluated the safety, efficacy and immune mechanisms of short-course treatment with adjuvant-free Lolium perenne peptides (LPP) following a 6-week dose-escalation protocol. METHODS: In a prospective, dose-escalation study, 61 grass pollen-allergic patients received 2 subcutaneous injections of LPP once weekly for 6 weeks. Safety was assessed evaluating local reactions, systemic reactions and adverse events. The clinical effect of LPP was determined by reactivity to the conjunctival provocation test (CPT). Specific IgE, IgG4 and blocking antibodies were measured at baseline (V1), during (V6) and after treatment (V8). RESULTS: No fatality, serious adverse event or epinephrine use was reported. Mean wheal diameters after injections were <0.6 cm and mean redness diameters <2.5 cm, independent of dose. Transient and mostly mild adverse events were reported in 33 patients. Two patients experienced a grade I and 4 patients a grade II reaction (AWMF classification). At V8, 69.8% of patients became nonreactive to CPT. sIgG4 levels were higher at V6 (8.1-fold, P < .001) and V8 (12.2-fold, P < .001) than at V1. The sIgE:sIgG4 ratio decreased at V6 (-54.6%, P < .001) and V8 (-71.6%, P < .001) compared to V1. The absolute decrease in IgE-facilitated allergen binding was 18% (P < .001) at V6 and 25% (P < .001) at V8. CONCLUSION: Increasing doses of subcutaneous LPP appeared safe, substantially diminished reactivity to CPT and induced blocking antibodies as early as 4 weeks after treatment initiation. The benefit/risk balance of LPP immunotherapy remains to be further evaluated in large studies.
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Linfocitos B/inmunología , Desensibilización Inmunológica , Tolerancia Inmunológica , Lolium/inmunología , Péptidos/inmunología , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/terapia , Adolescente , Adulto , Alérgenos/inmunología , Linfocitos B/metabolismo , Niño , Preescolar , Desensibilización Inmunológica/efectos adversos , Desensibilización Inmunológica/métodos , Femenino , Humanos , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Pruebas de Provocación Nasal , Polen/inmunología , Rinitis Alérgica Estacional/diagnóstico , Adulto JovenRESUMEN
Nasal allergen challenge (NAC) is an important tool to diagnose allergic rhinitis. In daily clinical routine, experimentally, or when measuring therapeutic success clinically, nasal allergen challenge is fundamental. It is further one of the key diagnostic tools when initiating specific allergen immunotherapy. So far, national recommendations offered guidance on its execution; however, international divergence left many questions unanswered. These differences in the literature caused EAACI to initiate a task force to answer unmet needs and find a consensus in executing nasal allergen challenge. On the basis of a systematic review containing nasal allergen challenges of the past years, task force members reviewed evidence, discussed open issues, and studied variations of several subjective and objective assessment parameters to propose a standardized way of a nasal allergen challenge procedure in clinical practice. Besides an update on indications, contraindications, and preparations for the test procedure, main recommendations are a bilaterally challenge with standardized allergens, with a spray device offering 0.1 mL per nostril. A systematic catalogue for positivity criteria is given for the variety of established subjective and objective assessment methods as well as a schedule for the challenge procedure. The task force recommends a unified protocol for NAC for daily clinical practice, aiming at eliminating the previous difficulty of comparing NAC results due to unmet needs.
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Comités Consultivos , Alérgenos/administración & dosificación , Pruebas de Provocación Nasal/normas , Pruebas de Provocación Nasal/tendencias , Rinitis Alérgica/diagnóstico , Administración Intranasal , Cuidados Posteriores , Anafilaxia , Alemania , Humanos , Inmunoglobulina E/sangre , Mucosa Nasal/inmunología , Obstrucción Nasal/inmunología , Pruebas de Provocación Nasal/métodos , Rociadores Nasales , Prurito/inmunología , Pruebas Cutáneas , Estornudo/inmunologíaRESUMEN
Allergic rhinoconjunctivitis (AR) is an allergic disorder of the nose and eyes affecting about a fifth of the general population. Symptoms of AR can be controlled with allergen avoidance measures and pharmacotherapy. However, many patients continue to have ongoing symptoms and an impaired quality of life; pharmacotherapy may also induce some side-effects. Allergen immunotherapy (AIT) represents the only currently available treatment that targets the underlying pathophysiology, and it may have a disease-modifying effect. Either the subcutaneous (SCIT) or sublingual (SLIT) routes may be used. This Guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on AIT for AR and is part of the EAACI presidential project "EAACI Guidelines on Allergen Immunotherapy." It aims to provide evidence-based clinical recommendations and has been informed by a formal systematic review and meta-analysis. Its generation has followed the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included involvement of the full range of stakeholders. In general, broad evidence for the clinical efficacy of AIT for AR exists but a product-specific evaluation of evidence is recommended. In general, SCIT and SLIT are recommended for both seasonal and perennial AR for its short-term benefit. The strongest evidence for long-term benefit is documented for grass AIT (especially for the grass tablets) where long-term benefit is seen. To achieve long-term efficacy, it is recommended that a minimum of 3 years of therapy is used. Many gaps in the evidence base exist, particularly around long-term benefit and use in children.
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Conjuntivitis Alérgica/prevención & control , Desensibilización Inmunológica/métodos , Desensibilización Inmunológica/normas , Rinitis Alérgica/prevención & control , HumanosRESUMEN
BACKGROUND: A novel subcutaneous allergen immunotherapy formulation (gpASIT+™) containing Lolium perenne peptides (LPP) and having a short up-dosing phase has been developed to treat grass pollen-induced seasonal allergic rhinoconjunctivitis. We investigated peptide immunotherapy containing the hydrolysate from perennial ryegrass allergens for the optimum dose in terms of clinical efficacy, immunogenicity and safety. METHODS: This prospective, double-blind, placebo-controlled, phase IIb, parallel, four-arm, dose-finding study randomized 198 grass pollen-allergic adults to receive placebo or cumulative doses of 70, 170 or 370 µg LPP. All patients received weekly subcutaneous injections, with the active treatment groups reaching assigned doses within 2, 3 and 4 weeks, respectively. Efficacy was assessed by comparing conjunctival provocation test (CPT) reactions at baseline, after 4 weeks and after completion. Grass pollen-specific immunoglobulins were analysed before and after treatment. RESULTS: Conjunctival provocation test (CPT) response thresholds improved from baseline to V7 by at least one concentration step in 51.2% (170 µg; P = .023), 46.3% (370 µg), and 38.6% (70 µg) of patients receiving LPP vs 25.6% of patients receiving placebo (modified per-protocol set). Also, 39% of patients in the 170-µg group became nonreactive to CPT vs 18% in the placebo group. Facilitated allergen-binding assays revealed a highly significant (P < .001) dose-dependent reduction in IgE allergen binding across all treatment groups (70 µg: 17.1%; 170 µg: 18.8%; 370 µg: 26.4%). Specific IgG4 levels increased to 1.6-fold (70 µg), 3.1-fold (170 µg) and 3.9-fold (370 µg) (mPP). CONCLUSION: Three-week immunotherapy with 170 µg LPP reduced CPT reactivity significantly and increased protective specific antibodies.
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Conjuntivitis Alérgica/prevención & control , Desensibilización Inmunológica/métodos , Rinitis Alérgica Estacional/prevención & control , Adulto , Alérgenos/administración & dosificación , Alérgenos/inmunología , Antígenos de Plantas/administración & dosificación , Antígenos de Plantas/inmunología , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Lolium , Masculino , Péptidos/administración & dosificación , Péptidos/inmunologíaRESUMEN
BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis. To inform the development of clinical recommendations, we undertook a systematic review to assess the effectiveness, cost-effectiveness, and safety of AIT in the management of allergic rhinoconjunctivitis. METHODS: We searched nine international biomedical databases for published, in-progress, and unpublished evidence. Studies were independently screened by two reviewers against predefined eligibility criteria and critically appraised using established instruments. Our primary outcomes of interest were symptom, medication, and combined symptom and medication scores. Secondary outcomes of interest included cost-effectiveness and safety. Data were descriptively summarized and then quantitatively synthesized using random-effects meta-analyses. RESULTS: We identified 5960 studies of which 160 studies satisfied our eligibility criteria. There was a substantial body of evidence demonstrating significant reductions in standardized mean differences (SMD) of symptom (SMD -0.53, 95% CI -0.63, -0.42), medication (SMD -0.37, 95% CI -0.49, -0.26), and combined symptom and medication (SMD -0.49, 95% CI -0.69, -0.30) scores while on treatment that were robust to prespecified sensitivity analyses. There was in comparison a more modest body of evidence on effectiveness post-discontinuation of AIT, suggesting a benefit in relation to symptom scores. CONCLUSIONS: AIT is effective in improving symptom, medication, and combined symptom and medication scores in patients with allergic rhinoconjunctivitis while on treatment, and there is some evidence suggesting that these benefits are maintained in relation to symptom scores after discontinuation of therapy.
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Conjuntivitis Alérgica/terapia , Desensibilización Inmunológica/métodos , Rinitis Alérgica Estacional/terapia , Alérgenos/inmunología , Bases de Datos Factuales , HumanosRESUMEN
BACKGROUND: Allergen immunotherapy (AIT) is an effective treatment for allergic rhinoconjunctivitis (AR) with or without asthma. It is important to note that due to the complex interaction between patient, allergy triggers, symptomatology and vaccines used for AIT, some patients do not respond optimally to the treatment. Furthermore, there are no validated or generally accepted candidate biomarkers that are predictive of the clinical response to AIT. Clinical management of patients receiving AIT and efficacy in randomised controlled trials for drug development could be enhanced by predictive biomarkers. METHOD: The EAACI taskforce reviewed all candidate biomarkers used in clinical trials of AR patients with/without asthma in a literature review. Biomarkers were grouped into seven domains: (i) IgE (total IgE, specific IgE and sIgE/Total IgE ratio), (ii) IgG-subclasses (sIgG1, sIgG4 including SIgE/IgG4 ratio), (iii) Serum inhibitory activity for IgE (IgE-FAB and IgE-BF), (iv) Basophil activation, (v) Cytokines and Chemokines, (vi) Cellular markers (T regulatory cells, B regulatory cells and dendritic cells) and (vii) In vivo biomarkers (including provocation tests?). RESULTS: All biomarkers were reviewed in the light of their potential advantages as well as their respective drawbacks. Unmet needs and specific recommendations on all seven domains were addressed. CONCLUSIONS: It is recommended to explore the use of allergen-specific IgG4 as a biomarker for compliance. sIgE/tIgE and IgE-FAB are considered as potential surrogate candidate biomarkers. Cytokine/chemokines and cellular reponses provided insight into the mechanisms of AIT. More studies for confirmation and interpretation of the possible association with the clinical response to AIT are needed.
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Asma/diagnóstico , Asma/terapia , Conjuntivitis Alérgica/diagnóstico , Conjuntivitis Alérgica/terapia , Desensibilización Inmunológica , Rinitis Alérgica/diagnóstico , Rinitis Alérgica/terapia , Alérgenos/inmunología , Asma/inmunología , Basófilos/inmunología , Basófilos/metabolismo , Biomarcadores , Conjuntivitis Alérgica/inmunología , Citocinas/metabolismo , Desensibilización Inmunológica/métodos , Humanos , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Pronóstico , Rinitis Alérgica/inmunología , Resultado del TratamientoRESUMEN
In this review, we report on relevant current topics in allergen immunotherapy (AIT) which were broadly discussed during the first Aarhus Immunotherapy Symposium (Aarhus, Denmark) in December 2015 by leading clinicians, scientists and industry representatives in the field. The aim of this symposium was to highlight AIT-related aspects of public health, clinical efficacy evaluation, mechanisms, development of new biomarkers and an overview of novel therapeutic approaches. Allergy is a public health issue of high socioeconomic relevance, and development of evidence-based action plans to address allergy as a public health issue ought to be on national and regional agendas. The underlying mechanisms are in the focus of current research that lays the ground for innovative therapies. Standardization and harmonization of clinical endpoints in AIT trials as well as current knowledge about potential biomarkers have substantiated proof of effectiveness of this disease-modifying therapeutic option. Novel treatments such as peptide immunotherapy, intralymphatic immunotherapy and use of recombinant allergens herald a new age in which AIT may address treatment of allergy as a public health issue by reaching a large fraction of patients.
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Alérgenos/inmunología , Desensibilización Inmunológica , Hipersensibilidad/inmunología , Hipersensibilidad/terapia , Biomarcadores , Ensayos Clínicos como Asunto , Desensibilización Inmunológica/efectos adversos , Desensibilización Inmunológica/métodos , Manejo de la Enfermedad , Humanos , Hipersensibilidad/diagnóstico , Hipersensibilidad/prevención & control , Tolerancia Inmunológica , Resultado del TratamientoRESUMEN
BACKGROUND: Clinical efficacy of pollen allergen immunotherapy (AIT) has been broadly documented in randomized controlled trials. The underlying clinical endpoints are analysed in seasonal time periods predefined based on the background pollen concentration. However, any validated or generally accepted definition from academia or regulatory authorities for this relevant pollen exposure intensity or period of time (season) is currently not available. Therefore, this Task Force initiative of the European Academy of Allergy and Clinical Immunology (EAACI) aimed to propose definitions based on expert consensus. METHODS: A Task Force of the Immunotherapy and Aerobiology and Pollution Interest Groups of the EAACI reviewed the literature on pollen exposure in the context of defining relevant time intervals for evaluation of efficacy in AIT trials. Underlying principles in measuring pollen exposure and associated methodological problems and limitations were considered to achieve a consensus. RESULTS: The Task Force achieved a comprehensive position in defining pollen exposure times for different pollen types. Definitions are presented for 'pollen season', 'high pollen season' (or 'peak pollen period') and 'high pollen days'. CONCLUSION: This EAACI position paper provides definitions of pollen exposures for different pollen types for use in AIT trials. Their validity as standards remains to be tested in future studies.
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Conjuntivitis Alérgica/inmunología , Conjuntivitis Alérgica/terapia , Desensibilización Inmunológica , Exposición a Riesgos Ambientales/efectos adversos , Polen/inmunología , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/terapia , Ensayos Clínicos como Asunto , Conjuntivitis Alérgica/diagnóstico , Desensibilización Inmunológica/métodos , Relación Dosis-Respuesta Inmunológica , Humanos , Guías de Práctica Clínica como Asunto , Rinitis Alérgica Estacional/diagnóstico , Estaciones del Año , Evaluación de Síntomas , Factores de TiempoRESUMEN
This is an updated guideline for the diagnosis and management of allergic and non-allergic rhinitis, first published in 2007. It was produced by the Standards of Care Committee of the British Society of Allergy and Clinical Immunology, using accredited methods. Allergic rhinitis is common and affects 10-15% of children and 26% of adults in the UK, it affects quality of life, school and work attendance, and is a risk factor for development of asthma. Allergic rhinitis is diagnosed by history and examination, supported by specific allergy tests. Topical nasal corticosteroids are the treatment of choice for moderate to severe disease. Combination therapy with intranasal corticosteroid plus intranasal antihistamine is more effective than either alone and provides second line treatment for those with rhinitis poorly controlled on monotherapy. Immunotherapy is highly effective when the specific allergen is the responsible driver for the symptoms. Treatment of rhinitis is associated with benefits for asthma. Non-allergic rhinitis also is a risk factor for the development of asthma and may be eosinophilic and steroid-responsive or neurogenic and non- inflammatory. Non-allergic rhinitis may be a presenting complaint for systemic disorders such as granulomatous or eosinophilic polyangiitis, and sarcoidoisis. Infective rhinitis can be caused by viruses, and less commonly by bacteria, fungi and protozoa.
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Rinitis Alérgica/diagnóstico , Rinitis Alérgica/terapia , Rinitis/diagnóstico , Rinitis/terapia , Manejo de la Enfermedad , Humanos , Rinitis/epidemiología , Rinitis/etiología , Rinitis Alérgica/epidemiología , Rinitis Alérgica/etiologíaRESUMEN
Allergic diseases often occur early in life and persist throughout life. This life-course perspective should be considered in allergen immunotherapy. In particular it is essential to understand whether this al treatment may be used in old age adults. The current paper was developed by a working group of AIRWAYS integrated care pathways for airways diseases, the model of chronic respiratory diseases of the European Innovation Partnership on active and healthy ageing (DG CONNECT and DG Santé). It considered (1) the political background, (2) the rationale for allergen immunotherapy across the life cycle, (3) the unmet needs for the treatment, in particular in preschool children and old age adults, (4) the strategic framework and the practical approach to synergize current initiatives in allergen immunotherapy, its mechanisms and the concept of active and healthy ageing.
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Rhinitis is a heterogeneous condition that has been associated with inflammatory responses as in allergic rhinitis but can also occur in the absence of inflammation such as in so-called idiopathic (previously 'vasomotor') rhinitis. Allergic rhinitis affects approximately one in four of the population of westernized countries and is characterized by typical symptoms of nasal itching, sneezing, watery discharge and congestion. The intention of this review is to illustrate key concepts of the pathogenesis of rhinitis. Imbalance in innate and adaptive immunity together with environmental factors is likely to play major roles. In allergic rhinitis, initial allergen exposure and sensitization involves antigen-presenting cells, T and B lymphocytes and results in the generation of allergen-specific T cells and allergen-specific IgE antibodies. On re-exposure to relevant allergens, cross-linking of IgE on mast cells results in the release of mediators of hypersensitivity such as histamine and immediate nasal symptoms. Within hours, there is an infiltration by inflammatory cells, particularly Th2 T lymphocytes, eosinophils and basophils into nasal mucosal tissue that results in the late-phase allergic response. Evidence for nasal priming and whether or not remodelling may be a feature of allergic rhinitis will be reviewed. The occurrence of so-called local allergic rhinitis in the absence of systemic IgE will be discussed. Non-allergic (non-IgE-mediated) rhinitis will be considered in the context of inflammatory and non-inflammatory disorders.
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Rinitis/etiología , Remodelación de las Vías Aéreas (Respiratorias) , Alérgenos/inmunología , Biomarcadores , Diagnóstico Diferencial , Humanos , Inmunoglobulina E/inmunología , Fenotipo , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Rinitis/diagnóstico , Rinitis/metabolismo , Rinitis/terapia , Rinitis Alérgica/diagnóstico , Rinitis Alérgica/inmunología , Rinitis Alérgica/metabolismo , Rinitis Alérgica/terapiaRESUMEN
BACKGROUND: Specific allergen immunotherapy (SIT) is an effective allergy treatment, but it is unclear whether SIT is effective for atopic eczema (AE). We undertook a systematic review to assess SIT efficacy and safety for treating AE. METHODS: We searched databases, ongoing clinical trials registers, and conference proceedings up to July 2015. Randomized controlled trials (RCTs) of SIT using standardized allergen extracts, compared with placebo/control, for treating AE in patients with allergic sensitization were eligible. RESULTS: We identified 12 eligible trials with 733 participants. Interventions included subcutaneous (six trials), sublingual (four trials), oral or intradermal SIT in children/adults allergic to house dust mite (10 trials), grass pollen or other inhalants. Risk of bias was moderate, with high loss to follow-up and nonblinding as the main concerns. For our primary outcomes, three studies (208 participants) reported no significant difference - patient-reported global disease severity improvement RR 0.75 (95% CI 0.45, 1.26); and eczema symptoms mean difference -0.74 on a 20-point scale (95% CI -1.98, 0.50). Two studies (85 participants) reported a significant difference - SIT improved global disease severity RR 2.85 (95% CI 1.02, 7.96); and itch mean difference -4.20 on a 10-point scale (95% CI -3.69, -4.71). Meta-analysis was limited due to extreme statistical heterogeneity. For some secondary outcomes, meta-analyses showed benefits for SIT, for example investigator-rated improvement in eczema severity RR 1.48 (95% CI 1.16, 1.88; six trials, 262 participants). We found no evidence of adverse effects. The overall quality of evidence was low. CONCLUSION: We found no consistent evidence that SIT is effective for treating AE, but due to the low quality of evidence further research is needed to establish whether SIT has a role in AE treatment.
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Dermatitis Atópica/terapia , Desensibilización Inmunológica , Eccema/terapia , Alérgenos/inmunología , Terapia Combinada , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/inmunología , Desensibilización Inmunológica/efectos adversos , Desensibilización Inmunológica/métodos , Eccema/inmunología , Humanos , Sesgo de Publicación , Calidad de Vida , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
Follicular helper T cells (Tfh ) are located within germinal centers of lymph nodes. Cognate interaction between Tfh , B cells, and IL-21 drives B cells to proliferate and differentiate into plasma cells thereby leading to antibody production. Tfh cells and IL-21 are involved in infectious and autoimmune diseases, immunodeficiencies, vaccination, and cancer. Human peripheral blood CXCR5(+) CD4(+) T cells comprise different subsets of Tfh -like cells. Despite the importance of the IgE response in the pathogenesis of allergic disorders, little is known about the role of follicular and blood Tfh cells and IL-21 in human and experimental allergic disease. Here, we review recent advances regarding the phenotypic and functional characteristics of both follicular and blood Tfh cells and of the IL-21/IL-21R system in the context of allergic disorders.
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Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Fenómenos del Sistema Inmunológico , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Comunicación Celular/inmunología , Diferenciación Celular/inmunología , Movimiento Celular/inmunología , Centro Germinal/citología , Centro Germinal/inmunología , Centro Germinal/metabolismo , Humanos , Inmunidad , Interleucinas/metabolismo , Ratones , Modelos Animales , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Colaboradores-Inductores/citologíaRESUMEN
BACKGROUND: The calcium-binding 2EF-hand protein Phl p 7 from timothy grass pollen is a highly cross-reactive pollen pan-allergen that can induce severe clinical symptoms in allergic patients. Recently, a human monoclonal Phl p 7-specific IgG4 antibody (mAb102.1F10) was isolated from a patient who had received grass pollen-specific immunotherapy (SIT). METHODS: We studied epitope specificity, cross-reactivity, affinity and cross-protection of mAb102.1F10 towards homologous calcium-binding pollen allergens. Sequence comparisons and molecular modelling studies were performed with ClustalW and SPADE, respectively. Surface plasmon resonance measurements were made with purified recombinant allergens. Binding and cross-reactivity of patients' IgE and mAb102.1F10 to calcium-binding allergens and peptides thereof were studied with quantitative RAST-based methods, in ELISA, basophil activation and IgE-facilitated allergen presentation experiments. RESULTS: Allergens from timothy grass (Phl p 7), alder (Aln g 4), birch (Bet v 4), turnip rape (Bra r 1), lamb's quarter (Che a 3) and olive (Ole e 3, Ole e 8) showed high sequence similarity and cross-reacted with allergic patients' IgE. mAb102.1F10 bound the C-terminal portion of Phl p 7 in a calcium-dependent manner. It cross-reacted with high affinity with Ole e 3, whereas binding and affinity to the other allergens were low. mAb102.1F10 showed limited cross-inhibition of patients' IgE binding and basophil activation. Sequence comparison and surface exposure calculations identified three amino acids likely to be responsible for limited cross-reactivity. CONCLUSIONS: Our results demonstrate that a small number of amino acid differences among cross-reactive allergens can reduce the affinity of binding by a SIT-induced IgG and thus limit cross-protection.
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Alérgenos/inmunología , Reacciones Cruzadas/inmunología , Epítopos/inmunología , Inmunoglobulina G/inmunología , Inmunoterapia , Polen/inmunología , Alérgenos/química , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos/inmunología , Antígenos de Plantas , Calcio/metabolismo , Epítopos/química , Humanos , Inmunoglobulina E/inmunología , Modelos Moleculares , Péptidos/inmunología , Unión Proteica/inmunología , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunologíaRESUMEN
Experimental evolution has provided little support for the hypothesis that the narrow diets of herbivorous insects reflect trade-offs in performance across hosts; selection lines can sometimes adapt to an inferior novel host without a decline in performance on the ancestral host. An alternative approach for detecting trade-offs would be to measure adaptation decay after selection is relaxed, that is, when populations newly adapted to a novel host are reverted to the ancestral one. Lines of the seed beetle Callosobruchus maculatus rapidly adapted to a poor host (lentil); survival in lentil seeds increased from 2% to > 90% in < 30 generations. After the lines had reached a plateau with respect to survival in lentil, sublines were reverted to the ancestral host, mung bean. Twelve generations of reversion had little effect on performance in lentil, but after 25-35 generations, the reverted lines exhibited lower survival, slower development and smaller size. The most divergent pair of lines was then assayed on both lentil and mung bean. Performance on lentil was again much poorer in the reverted line than in the nonreverted one, but the lines performed equally well on mung bean. Moreover, the performance of the nonreverted line on mung bean remained comparable to that of the original mung-bean population. Our results thus present a paradox: loss of adaptation to lentil following reversion implies a trade-off, but the continued strong performance of lentil-adapted lines on mung bean does not. Genomic comparisons of the reverted, nonreverted and ancestral lines may resolve this paradox and determine the importance of selection vs. drift in causing a loss of adaptation following reversion.