Background: Peanut allergy has a rising prevalence in high-income countries, affecting 0.5–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents. Methods: Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food induced anaphylaxis cases in a tertiary paediatric allergy centre. Results: 3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs 38%; p=0.001), asthma comorbidity (47% vs 35%; p<0.001), relevant co-factors (29% vs 22%; p=0.004) and biphasic reactions (10% vs 4%; p=0.001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs 56% and grade IV 1.1% vs 0.9%; p=0.001). Self-administration of intramuscular adrenaline was low (17% vs 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs 26%; p=0.003). Hospitalisation was higher for peanut anaphylaxis (67% vs 54%; p=0.004). Conclusions: The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g. presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.

Background: It is unclear if asthma and its allergic phenotype are risk factors for hospitalization or severe disease from SARS-CoV-2. Methods: All patients testing positive for SARS-CoV-2 between March 1 and September 30, 2020, were retrospectively identified and characterized through electronic analysis at Stanford. A sub-cohort was followed prospectively to evaluate long-term COVID-19 symptoms. Results: 168,190 patients underwent SARS-CoV-2 testing, and 6,976 (4·15%) tested positive. In a multivariate analysis, asthma was not an independent risk factor for hospitalization (OR 1·12 [95% CI 0·86, 1·45], p=0·40). Among SARS-CoV-2 positive asthmatics, allergic asthma lowered the risk of hospitalization and had a protective effect compared to non-allergic asthma (OR 0·52 (0·28, 0·91), p=0·026); there was no association between baseline medication use as characterized by GINA and hospitalization risk. Patients with severe COVID-19 disease had lower eosinophil levels during hospitalization compared to patients with mild or asymptomatic disease, independent of asthma status (p=0.0014). In a patient sub-cohort followed longitudinally, asthmatics and non-asthmatics had similar time to resolution of COVID-19 symptoms, particularly lower respiratory symptoms. Conclusions: Asthma is not a risk factor for more severe COVID-19 disease. Allergic asthmatics were half as likely to be hospitalized with COVID-19 compared to non-allergic asthmatics. Lower levels of eosinophil counts (allergic biomarkers) were associated with more severe COVID-19 disease trajectory. Recovery was similar among asthmatics and non-asthmatics with over 50% of patients reporting ongoing lower respiratory symptoms three months post-infection.

Because of their selectivity, biologicals are crucial therapeutic agents in oncological, immunological, and inflammatory diseases and their use in clinical practice is broadening. Biologicals are among the most common drugs that can cause hypersensitivity reactions (HSRs), and this is primarily attributed to an explosion in new treatment options that has developed through personalized and precision medicine. Patients can develop HSRs to these agents during the first lifetime exposure or after repeated exposure. Despite its relatively high prevalence, the underlying mechanisms and optimal management of HSRs to biologicals remain incompletely explained. In this position paper, the authors provided evidence-based recommendations for the diagnosis and management of HSRs to biologicals. Additionally, the document defines unmet needs, which should be topics of future studies.

This systematic review evaluates the efficacy, safety and economic impact of dupilumabcompared to standard of care for uncontrolled moderate-to-severe atopic dermatitis (AD). Pubmed, EMBASE and Cochrane Library were searched for RCTs and health economic evaluations. Critical and important AD-related outcomes were considered. The risk of bias and the certainty of the evidence were assessed using GRADE. Seven RCTs including 1845 subjects > 12 years treated with dupilumab16 to 52 weeks were evaluated. For adultsthere is high certainty that dupilumabdecreasesSCORAD (MD -30,72; 95%CI -34,65% to -26,79%) and EASI-75 (RR 3.09; 95%CI 2.45 to 3.89), pruritus (RR 2.96; 95%CI 2.37 to 3.70), rescue medication (RR 3.46; 95%CI 2.79 to 4.30), sleep disturbance (MD -7.29; 95%CI -8.23 to -6.35), anxiety/depression (MD -3.08; 95% CI -4.41 to -1.75) and improves quality of life (MD -4.80; 95% CI -5.55 to -4.06). The efficacy for adolescents is similar. Dupilumab-related adverse events (AEs) slightly increase (low certainty). The evidence for dupilumab-related serious AE is uncertain. The incremental cost-effectiveness ratio ranged from 28,500 £ (low certainty) to 124,541 US$ (moderate certainty).More data on long term safety are needed both for children and adults, together with more efficacy data in the paediatric population.

Adolescent and young adult (AYA) patients need additional support while they experience the challenges associated with their age. They need specific training to learn the knowledge and skills required to confidently self-manage their allergies and/or asthma. Transitional care is a complex process which should address the psychological, medical, educational and vocational needs of AYA in the developmentally appropriate way. The European Academy of Allergy and Clinical Immunology has developed a clinical practice guideline to provide evidence-based recommendations for healthcare professionals to support the transitional care of AYA with allergy and/or asthma. This guideline was developed by a multi-disciplinary working panel of experts and patient representatives based on two recent systematic reviews. It sets out a series of general recommendations on operating a clinical service for AYA, which include: (i) starting transition early (11-13 years), (ii) using a structured, multidisciplinary approach, (iii) ensuring AYA fully understand their condition and have resources they can access, (iv) active monitoring of adherence and (v) discussing any implications for further education and work. Specific allergy and asthma transition recommendations include (i) simplifying medication regimes and using reminders; (ii) focusing on areas where AYA are not confident and involving peers in training AYA patients; (iii) identifying and managing psychological and socioeconomic issues impacting disease control and quality of life; (iv) enrolling the family in assisting AYA to undertake self-management and (v) encouraging AYA to let their friends know about their allergies and asthma. These recommendations may need to be adapted to fit into national healthcare systems.

Sweet syndrome induced by SARS-CoV-2 Pfizer-BioNTech mRNA vaccineAS Darrigade, MD1, H Théophile, MD2, P Sanchez-Pena, MD2, B Milpied, MD1, M Colbert4, MD, S Pedeboscq5, MD, T Pistone6, MD, ML Jullié, MD7, J Seneschal, MD, PhD1,31 : Department of Adult and Pediatric Dermatology, Bordeaux University Hospitals, France2 : Department of pharmacovigilancy, Bordeaux University Hospitals, France3 : Research Unit INSERM U10354 : Department of geriatry, Clinic Bordeaux Nord, Bordeaux, France5 : Department of pharmacology, Bordeaux University Hospitals, France6: Department of infectious disease, Bordeaux University Hospitals, France7: Department of anatomopathology, Bordeaux University Hospitals, FranceManuscript word count: 607Key words : sweet syndrome, SARS-CoV-2, Pfizer-BioNTech mRNA vaccine, delayed hypersensitivity, IDRCorresponding author: A.S. Darrigade, Dermatology Department, Saint-André Hospital, 1, rue Jean Burguet 33000 Bordeaux, FrancePhone: +33556794705Fax: [email protected] source: No financial disclosuresFinancial Disclosure: No external funding for this manuscriptTo the editor,A 45-year-old woman, without any past medical history or allergy presented in our clinic with a rapid onset of diffuse skin eruptions. Five days earlier, she received the first injection of the SARS-CoV-2 Pfizer-BioNTech mRNA. Concomitantly she took 1000mg paracetamol to prevent any post-vaccination syndrome. She well tolerated the preceding vaccines (influenza every year) before this one.The eruption started 24h after vaccine injection and was composed at time of the clinical exam of erythematous infiltrated papulosis located all over the body, without face involvement (Figure 1). No other extracutaneous symptoms were noted. Blood exams showed increased blood count levels with increased neutrophils count (8.77G/l), hepatic cytolysis (AST 67UI/L and ALT 116UI/l) with high level of PCR (115mg/l). SARS-CoV-2 PCR test and serology were negative. Viral tests for EBV, CMV, parvovirus B19, and Herpes simplex/Herpes zoster showed only a slight EBV reactivation. Histopathological examination of the skin biopsy showed a hyperplastic epidermis with an edematous papillary dermis. A superficial and deep dermal perivascular, periadnexal and interstitial dense infiltrate composed of neutrophils, eosinophils and lymphocytes was also a feature. Leukocytoclastic vasculitis was also seen (Figure 2A-2B). Clinical and pathological exams were compatible with the diagnosis of SS induced by SARS-CoV-2 Pfizer-BioNTech mRNA vaccine. Systemic steroid therapy (prednisone 0.5mg/kg/d) for five days was started and led to rapid improvement of the skin condition without any recurrence after treatment discontinuation. She did not receive the second vaccine injection.Patch-tests performed (14 days after steroid treatment stop, one month after SS) on both on healed and normal skin with pur SARS-CoV-2 Pfizer-BioNTech mRNA vaccine prepared less than 4 hours before were negative (Figure 1C 2-3). Then, intradermoreaction (IDR) with vaccine diluted at 1/10 on normal skin was positive in delayed reading (Figure 1C 1). Cutaneous biopsy was realized on the positive IDR reaction, showing an abundant inflammatory infiltrate predominantly with lymphocytes (Figure 2C).Cutaneous reactions after vaccine injection are rare, and heterogenous1. They could be related to the vaccine or the adjuvant. In addition, vaccine could trigger flares of chronic inflammatory conditions as it was previously reported1. At that time, minor local side effects are reported with SARS-CoV-2 vaccines such as pain, swelling or redness; hypersensitivity reactions were anaphylactic reaction but no severe delayed hypersensitivity are reported2-3. Three cases of acute febrile neutrophilic dermatosis are reported in the international bank of WHO, one in United Kingdom, one in United States of America and our case. Under SARS-CoV-2 Pfizer-BioNTech mRNA vaccine four cases of vasculitis had been reported after injection. In France one case of relapse of neutrophilic disorder was reported one day after SARS-CoV-2 Pfizer-BioNTech mRNA vaccine. The adjuvant associated with the SARS-CoV-2 Pfizer-BioNTech mRNA vaccine is polyethylene glycol (PEG) 20003. However our patient never received infusion containing PEG or polysorbate before. Patch-tests with PEG or polysorbate alone were not performed because of the negativity of the patch-test with the SARS-CoV-2 Pfizer-BioNTech mRNA vaccine. Only 10 cases of SS induced by vaccine are published so far including: 3 with seasonal influenza, 1 with influenza A, 2 with pneumococcal, 2 tuberculosis, 2 small pox4. SS is an acute inflammatory skin disease associated with important infiltration of neutrophils. Leukocytoclastic vasculitis could be present in SS5. One case of SS in a patient receiving pneumococcal vaccine showed the presence of dermal vasculitis associated with infiltration of neutrophils6. In case of anaphylactic reaction under SARS-CoV-2 Pfizer-BioNTech mRNA vaccine, the risk of relapse with the Moderna SARS-CoV-2 mRNA vaccine or SARS-CoV-2 vaccines with an adenovirus carrier and protein subunit remains unknown3, in case of SS even more.To conclude we report the first case of SS induce by SARS-CoV-2 Pfizer-BioNTech mRNA vaccine confirmed by positive IDR.

COVID-19 Clinical trials: quality matters more than quantity

To the Editor: Asthma is a complex and heterogeneous chronic airway inflammatory disease with the involvement of environmental factors through epigenetic mechanisms.1 Accordingly, repeated injury, repair and regeneration of the airway epithelium following exposure to environmental factors and inflammation results in histological changes and functional abnormalities in the airway mucosal epithelium, which are associated with the pathophysiology of asthma.2Epigenetics is defined by heritable changes in gene expression without changes in the DNA sequence.3 Regulation of gene expression is mediated by different mechanisms such as DNA methylation, histone modifications and RNA-associated silencing by small non-coding RNAs. CpG sites are dinucleotides consisting of guanine and cytosine concentrated in clusters referred to CpG islands found at important regulatory sites, such as promoter and enhancer regions.4 Their de novo methylation occurs in response to various cellular stressors and signals by DNA methyltransferases (DNMT3a and 3b), which add a methyl group to position 5 of cytosine residues at the CpG site. During DNA replication both of the separated strands of DNA carry one methylated cytosine to be used as a template for duplication. Daughter DNA duplex strands will thus be hemi-methylated, which is recognized by a different DNA methyltransferase isoform (DNMT1).5 Because DNA methylation is a reversible process, the DNMTs are considered as a therapeutic target. Several DNMT inhibitors have been identified recently, among the non-nucleoside inhibitors, 4-aminoquoline-based inhibitors, such as SGI-1027 showed potent inhibitory activity. SGI-1027 occupies the binding site of DNMTs resulting in the prevention of access of target DNA to the substrate binding pocket.6We have demonstrated in previous studies from our laboratory that human primary bronchial epithelial cells (HBEC) isolated from patients with asthma showed lower barrier integrity compared to controls.7 To investigate the level of global methylation in HBEC, we investigated control and asthma samples for the long interspersed nuclear element-1 (LINE-1) methylation levels (Figure 1A). HBEC from asthma patients showed a tendency for higher global methylation levels, together with higher expression of 5-methylcytosine (5-mc) in immunofluorescence staining (Figure 1B). Next, we performed methylation profiling (Illumina Infinium EPIC array) to investigate genes methylated in ALI cultures of HBEC. Interestingly, in a highly methylated group of top 100 genes, we found many genes associated with cell growth, ion transport, and cytoskeletal remodeling (Figure S1). We kept our attention on the methylated epigenetic and tight junction (TJ) genes and further focused on TJs, especially zonula occludens and claudins which showed higher methylation in contrast to occludin, which was not methylated (Figure S2). As higher methylation levels were observed in HBEC of asthmatic origin, we inhibited the DNA methyltransferase enzyme with a specific inhibitor, SGI-1027, to demonstrate the role of CpG methylation on epithelial barrier integrity. ALI cultures were treated with the DNA methyltransferase inhibitor for 72 hours. Significantly decreased expression of 5-mc was observed after 48 hours of DNA-methyltransferase inhibition, demonstrating that the methylation of 5-methylcytosine (5-mc) in bronchial epithelium was reversed (Figure 2A). This prompted us to investigate the changes triggered by the inhibitor in epithelial cells. Further experiments showed increased transepithelial electric resistance (TER) in bronchial epithelial cells, in ALI from asthmatic donors after 48 hours of DNMT inhibition (Figure 2B). The link between barrier integrity and TER results were confirmed by the significantly decreased paracellular passage of FITC-labelled 4kD dextran after inhibition of DNMTs (Figure 2C). The reconstitution of TER in asthmatic ALI was associated with decreased protein DNMT1 expression and increased ZO-1 and claudin-18 proteins (Figure 2D). We also observed increased claudin-4, but not occludin expression upon DNMT inhibition (Figure S3). Increased expression of ZO-1 with an intact and honeycomb-like structure in the immunofluorescence staining of bronchial epithelial cells confirmed the effect on protein expression of bronchial epithelial barrier in asthma donors (Figure S4).Defective epithelial barrier has been established in asthma in addition to several chronic inflammatory diseases.8 Direct targeting of the epithelial barrier leakiness for the treatments represents an important target, however so far there is no treatment possibility targeting epigenetic mechanisms. The present study demonstrates an increased global methylation level in HBEC from asthmatic individuals. CpG methylation of specific genes is essential for the defect of epithelial barrier integrity, which is reversed upon DNMT inhibition. The inversion of CpG methylation, restores leakiness in the epithelium in asthma by increasing TER, decreasing paracellular flux and improves the structure of bronchial epithelial cells by increasing the expression of TJ proteins. The better understanding of the importance of epigenetic memory in chronic tissue inflammatory diseases together with the availability of treatment modalities targeting epigenetic mechanisms and transition of these molecules into the clinical studies may lead to curative treatment of allergic and autoimmune inflammatory diseases.9Paulina Wawrzyniak1, PhD,Krzysztof Krawczyk1,3, MSc,Swati Acharya5, PhD,Ge Tan1,7, PhD,Marcin Wawrzyniak1, PhD,Emmanuel Karouzakis4, PhD,Anita Dreher, Sci. Tech.,Bogdan Jakiela2, MD, PhD,Can Altunbulakli1, PhD,Marek Sanak2, MD, PhD,Liam O‘Mahony1,6, PD, PhD,Kari Nadeau5, MD, PhD,Cezmi A. Akdis1, MD1Swiss Institute of Allergy and Asthma Research (SIAF), University of Zürich, Davos, Switzerland, Christine Kühne-Center for Allergy Research and Education (CK-CARE)2Department of Medicine, Jagiellonian University Medical College, Krakow, Poland3Faculty of Biology and Environmental Protection, Department of Cellular Immunology, Lodz, Poland4Department of Rheumatology, University Hospital of Zurich5Departament of Medicine, Stanford University, United States6 Department of Medicine and School of Microbiology, APC Microbiome Ireland, University College Cork, Cork, Ireland.7 Functional Genomics Center Zurich, ETH Zurich/University of ZurichCorresponding author:Paulina WawrzyniakSwiss Institute of Allergy and Asthma Research (SIAF), University of Zürich, Davos, SwitzerlandObere Strasse 22,7270 Davos, SwitzerlandTel: +41 81 410 08 48Fax: +41 81 410 08 [email protected] of interest:The authors declare that they have no conflicts of interest.Founding sources:Supported by Swiss National Science Foundation grants 310030_156823, and 320030_176190.Word count: 765Keywords: asthma, tight junction, CpG methylation, DNA methyltransferases,

Coronavirus disease 2019 (COVID-19), a respiratory tract infection caused by a novel human coronavirus, the severe acute respiratory syndrome coronavirus 2, leads to a wide spectrum of clinical manifestations ranging from asymptomatic cases to patients with mild and severe symptoms, with or without pneumonia. Given the huge influence caused by the overwhelming COVID-19 pandemic affecting over three million people worldwide, a wide spectrum of drugs is considered for the treatment in the concept of repurposing and off-label use. There is no knowledge about the diagnosis and clinical management of the drug hypersensitivity reactions that can potentially occur during the disease. This review brings together all the published information about the diagnosis and management of drug hypersensitivity reactions due to current and candidate off-label drugs and highlights relevant recommendations. Furthermore, it gathers all the dermatologic manifestations reported during the disease for guiding the clinicians to establish a better differential diagnosis of drug hypersensitivity reactions in the course of the disease.

The “coronavirus disease 2019 (COVID-19)” outbreak was first reported in December 2019 (China). Since then, this disease has rapidly spread across the globe and in March 2020 the World Health Organization (WHO) declared the COVID-19 pandemic.1 Since the outbreak was first announced, our journal has extensively focused on the clinical features, outcomes, diagnosis, immunology, and pathogenesis of COVID-19 and its infectious agent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We published our first COVID-19 article on 19 February, focusing for the first time on the clinical characteristics of 140 cases of human-to-human coronavirus transmission without any links to the Huanan Wet Market.2 Hypertension and diabetes were mentioned as risk factors and there was no increased prevalence in allergic patients. This early study reported that the main symptoms at hospital admission were fever (91.7%), cough (75.0%), fatigue (75.0%), gastrointestinal symptoms (39.6%), and dyspnea (36.7%). Lymphopenia and eosinopenia were also reported as important signs and biomarkers for monitoring and severity of the patients.2 The prevalent eosinopenia in COVID-19 patients and the possible anti-viral role of eosinophils were further discussed in several following publications inAllergy .3,4 Our second COVID-19 paper brought attention to the wide range of clinical manifestations of this disease, from asymptomatic cases to patients with mild and severe symptoms, with or without pneumonia as well as with only diarrhea.5Patients with common allergic diseases did not develop distinct symptoms and severe courses. Cases with pre-existing chronic obstructive pulmonary disease or complicated with a secondary bacterial pneumonia were severe. Another article, timely appearing in our journal, alerted the scientific community that even in experienced hands there was a 14.1% false negative polymerase chain reaction (PCR) diagnosis in COVID-19 cases and were later diagnosed positive after repeated tests.6 A pediatric article was also published extensively analyzing 182 cases and it was reported that children with COVID-19 showed a mild clinical course.7 Patients with pneumonia had a higher proportion of fever and cough and increased inflammatory biomarkers compared to those without pneumonia. There were 43 allergic patients in this series and there was no significant difference between allergic and non-allergic COVID-19 children in disease incidence, clinical features, laboratory, and immunological findings. Allergy was not a risk factor for disease and severity of SARS-CoV-2 infection and did not significantly influence the disease course of COVID-19 in children.7The immunology of COVID-19 was extensively reviewed in two articles from leading experts with a comprehensive discussion of the tip of the iceberg in COVID-19 epidemiology, anti-viral response, antibody response to SARS-CoV-2, acute phase reactants, cytokine storm, and pathogenesis of tissue injury and severity. 8,9Two studies timely reported the role of possible trained immunity in countries with a Bacillus Calmette-Guérin (BCG) vaccination programme and a relatively low COVID-19 prevalence and mortality rate.10,11 In an extensive RNA sequencing analyses of SARS-CoV-2 receptor and their molecular partners revealed that ACE2 and TMPRSS2 were coexpressed at the epithelial sites of the lung and skin, whereas CD147 (BSG), cyclophilins (PPIA and PPIB), CD26 (DPP4) and related molecules were expressed in both, epithelium and in immune cells.12Allergists, respiratory physicians, pediatricians, and other health care providers treating patients with allergic diseases are frequently in contact with patients potentially infected with SARS-CoV-2. Practical considerations and recommendations given by experts in the field of allergic diseases can provide useful recommendations for clinical daily work. Since the beginning of this current pandemic, our journal has disseminated clinical reports, 2,3,5,6,13 statements on the urgent need for accuracy in designing and reporting clinical trials in COVID-19,14 preventive measures,10,11,15 and Position Statements elaborated by experts in the field in close collaboration with the European Academy of Allergy and Clinical Immunology (EAACI) and its task force “Allergy and Its Impact on Asthma (ARIA) ”.16-28 (keynote information in table 1). A compendium answering 150 frequently encountered questions regarding COVID-19 and allergic diseases has been recently published by experts in their respective area.29 In addition, readers can put further questions regarding this “living ” compendium electronically to the authors and their answers will be available through a new category in the journal’s webpage.30Besides, EAACI in collaboration with ARIA, has provided recommendations on operational plans and practical procedures for ensuring optimal standards in the daily clinical care of patients with allergic diseases, whilst ensuring the safety of patients and healthcare workers.23Table 1: Examples of recently published recommendations, statements and Position Papers of the EAACI

EDITORIAL The average global temperatures on our planet are increasing due to rising anthropogenic greenhouse gases in the atmosphere, in particular carbon dioxide (CO2).1,2 There is an urgent need to call for action on global warming, which is resulting in extreme weather and related catastrophes.1 ,2 The Earth’s rising temperature is evidenced by warming of the oceans, melting glaciers, rising sea levels, and the diminished snow cover in the Northern Hemisphere. Climate-related factors can affect interactive atmospheric components (chemical and biological) and their interrelationship with human health.Climate change, a physics and meteorological event that affects health in the whole biosphere started to receive attention around the mid-twentieth century. Air pollution is the driving force of the Earth’s warming powered by the greenhouse effect (Figure 1). Environmental changes are occurring in frequency, intensity, type of precipitation, and extreme weather events, such as heatwaves, droughts, floods, blizzards, thunderstorms, sandstorms, and hurricanes. These are real and daunting challenges for the human and biosphere health, impacting the food and water supplies.1 ,2 Urbanization, with its high level of vehicle emissions and westernized lifestyle, is linked to the rising levels of particulate matter in the air, food supplies, soil, freshwater, and oceans. These environmental changes are correlated with the increased frequency of respiratory allergic diseases and bronchial asthma observed over recent decades in most industrialized countries and is continuously rising in developing countries.1-5This issue of Allergy focuses on the interrelationship between climate change, air pollution and human health.3-7Climate change is an important medical aspect in allergology as we are observing an increasing incidence of allergic diseases indirectly related to rising temperatures and are becoming a high socio-economic burden.1-3,8 Allergies and asthma appear to be at the front line of the sequelae of climate change along with infectious and cardiovascular diseases.1,5Cecchi et al. focus on the development and exacerbation of allergic diseases can be explained in terms of the exposome, a concept that includes all the environmental exposures from conception onwards. Multiple factors can trigger a pollen-induced respiratory allergy, such as airborne endotoxin levels and microbial composition of pollen, and these comprise a “pollen exposome”.4,9Susan Prescott has written an editorial in this issue bringing the attention to climate change and bidiversity aspects. At the time of Neil Armstrong’s lunar landing 50 years ago, Prof. Rene Dubos, a renowned microbiologist, delivered the seminal lecture “The Spaceship Earth”. He was ahead of his time and warned of an “altered immunity” driven by environmental problems and loss of biodiversity. Most of his predictions proved correct and we are now understanding at a molecular level the pathophysiological mechanisms involved in allergic diseases.8Climate change indirectly affects allergies by altering the pollen concentrations, allergenic potential, composition, migration of species and growth of new ones. Air pollution and climate change have resulted in the faster growth of allergenic plants, increasing the aeroallergen load for patients with inhalant allergy. Phenological studies indicate longer pollen seasons and emerge earlier in the year.1,4,5,8 Pollen and mold allergies are generally used to evaluate the interrelationship between air pollution and allergic respiratory diseases, such as rhinitis and asthma. Studies show that plants exhibit enhanced photosynthesis and reproductive effects and produce more pollen as a response to high atmospheric levels of CO2. 1,4,8 Pollen allergens have been demonstrated to trigger the release of pro-inflammatory and immunomodulatory mediators that accelerate the onset of allergy and the IgE-mediated sensitization. Lightning storms or wet conditions rupture the pollen grains releasing the allergenic proteins that cause asthma exacerbations in patients with pollinosis (thunderstorm-asthma).1,3,4,7,10 As a result of climate change, patients with seasonal allergic rhinoconjunctivitis and asthma have more intense symptoms and need stronger medication.1,4,8 In addition to respiratory illnesses, Fairweather et al. demonstrate the effect of environmental changes on cardiovascular, brain and mind, gastrointestinal, skin, immunologic and metabolic effects.1,3,4,7 The migration of stinging and biting insects to cooler climates has caused an increase in insect allergies in those areas.Prunicki et al. focus on the contribution of wildfires and deforestation and their contribution to global warming and immunological effects. It should be noted that in the last fifty years, half of the pluvial forests on Earth have been lost. Deforestation and forestation degradation is estimated to occur at a rate of 13 million hectares per year, mostly for agricultural purposes. Wildfires are becoming increasingly frequent, posing a serious risk to human health. The fine particulate matter (PM2.5) in wildfire smoke exacerbates asthma attacks, among other health problems. A study of 67 subjects demonstrated that those exposed to wildfire smoke had significantly higher levels of C-reactive protein and IL-1β compared with controls.6 The elevated levels of these two biomarkers are indicative of airway inflammation.Global warming and climate change need actions throughout the whole world with joined forces of all capabilities. These efforts are sometimes hampered by the unresponsiveness of governmental institutions and the general population, the lack of infrastructure and poverty. An action plan is needed to disseminate information on health-related problems associated with climate change. Patients with pollen allergies or asthma should be educated on the higher health risk during a thunderstorm or pollen season and the need for appropriate medication if staying outdoors. In collaboration with environmental organizations, physicians should take the lead to promote actions to mitigate air pollution and advocate the need to reduce global warming to protect our health.

Background: Although the importance of ectopic lymphoid tissues (eLTs) in the pathophysiology of nasal polyps (NPs) is increasingly appreciated, the mechanisms underlying their formation remain unclear. Objective: To study the role of IL-17A, CXCL13 and lymphotoxin (LT) in eLT formation in NPs. Methods: The expression of CXCL13 and LT as well as their receptors, and the phenotypes of stromal cells in NPs were studied by flow cytometry, immunostaining, and RT-PCR. Purified nasal stromal cells and polyp B cells were cultured and a murine model with nasal type 17 inflammation was established for the mechanistic study. Results: Excessive CXCL13 production was found in NPs and correlated with enhanced IL-17A expression. Stromal cells, with an expansion of CD31-Pdpn+ fibroblastic reticular cell (FRC) type, were the major source of CXCL13 in NPs without eLTs. IL-17A induced FRC expansion and CXCL13 production in nasal stromal cells. In contrast, B cells were the main source of CXCL13 and LTα1β2 in NPs with eLTs. CXCL13 upregulated LTα1β2 expression on polyp B cells, which in turn promoted CXCL13 production from polyp B cells and nasal stromal cells. LTα1β2 induced expansion of FRCs and CD31+Pdpn+ lymphoid endothelial cells, corresponding to the phenotypic characteristic of stromal cells in NPs with eLTs. IL-17A gene knockout, and CXCL13 and LTβR blockage diminished nasal eLT formation in the murine model. Conclusion: We identified an important role of IL-17A-induced stromal cell remodeling in the initiation, and crosstalk between B and stromal cells via CXCL13 and LTα1β2 in the enlargement of eLTs in NPs.

Adequate nasal breathing is indispensable for athletes and nasal symptoms have been shown to inter-fere with their subjective feeling of comfortable breathing and quality of life. Nasal symptoms are caused by either structural abnormalities or mucosal pathology. Structural pathologies are managed differently from mucosal disease and therefore adequate diagnosis is of utmost importance in athletes in order to choose the correct treatment option for the individual. Literature suggests that nasal symp-toms are more prevalent in athletes compared to the general population and certain sport environments might even trigger the development of symptoms. Given the high demands of respiratory function in athletes, insight into triggering factors is of high importance for disease prevention. Also, it has been suggested that athletes are more neglectful to their symptoms and hence remain undertreated, meaning that special attention should be paid to education of athletes and their caregivers. This review aims at giving an overview of nasal physiology in exercise as well as the possible types of nasal pathology. Additionally, diagnostic and treatment options are discussed and we focus on un-met needs for the management and prevention of these symptoms in athletes within the concept of precision medicine.

Treatment of Chronic Spontaneous Urticaria With Benralizumab: Report of Primary Endpoint Per Protocol Analysis, and Exploratory EndpointsStandard treatments for chronic spontaneous urticaria (CSU) including the second-generation H1-antihistamines (SGAH) are often ineffective even with four-times the FDA-recommended dose.1,2Eosinophilic infiltrates and an abundance of interleukin-5 (IL5) in CSU lesions (hives) support a role for IL5 in the pathomechanism of CSU.3 Thus, the use of biologic therapies, e.g. benralizumab targeting IL5-receptor-α, in treating SGAH-resistant CSU was hypothesized.A repeated-measures, 24-week study was designed and conducted at an urticaria clinic to determine clinical efficacy of benralizumab in CSU. Twelve SGAH-unresponsive CSU patients (3 males, 9 females; 2 blacks, 10 whites; between ages 32-65 years) having a median daily Urticaria Activity Score (UAS7)4 of 4, and pruritus severity ≥2 were enrolled. After a baseline run-in period, subjects were treated with a subcutaneous placebo dose followed by benralizumab 30mg subcutaneously every month (×3 doses) followed by two off-medication monthly-visits. Subject-reported responses to UAS7 and CU-QoL questionnaires were recorded at the monthly visits. The primary and exploratory endpoints were the change in UAS7 and Chronic Urticaria Quality-of-Life Total Score (CUQoLTS) respectively, from 4 weeks after placebo dose (visit 2) to 4 weeks after last dose of benralizumab (visit 5). Nine subjects completed the study; three withdrew after the first benralizumab dose. An intent-to-treat (ITT) analysis (n=12) of the primary endpoint has been reported previously.5Per-protocol (PP) analysis (n=9) of the primary endpoint, and PP vs. ITT of the exploratory endpoint are reported here. It was presumed that lesions were not self-limiting, and any improvement in outcomes during the study were because of intervention. Non-responders to benralizumab were identified if at any time during the 16 weeks after the first benralizumab dose there was <40% improvement in UAS7 from baseline vs. responders if UAS7 was ≤6.The average duration of urticarial symptoms was 7.0 years. Baseline UAS7 and CUQoLTS ranged between 22-42 and 36-95 respectively. Both outcomes significantly improved at visit 5 vs. visit 2 in 7 of 9 (78%) subjects completing the study. The average difference (95% CL) between visit 2 and visit 5 for UAS7, was -15.5 (-4.1, -26.8, p=0.003) and for CUQoLTS, using ITT analysis, was-13.2 (-2.4, -24.0, p=0.0005) or, using PP analysis, was -11.6 (-0.8, -22.4, p=0.03) (Figure-1 ). Five responders reported no hives/pruritus (UAS7=0) at visit 5 or 6.Between responders and non-responders, the average age (51.6 vs. 53, p=0.9) and symptom duration (5 vs. 9 years, p=0.5) did not differ significantly. However, the adjusted mean UAS7 percentage difference, adjusted for symptom duration, age, and blood eosinophils (eos%), from visit 2 till visit 5 was -84% for responders and +7.5% for non-responders, p=0.0009 (Table-1) . The average baseline UAS7 was not statistically significant (27 vs. 37.5, p=0.5) between groups however, the baseline mean difference for eos% was -6±1 (p=0.001), and for basophil% was -1.2±0.2, p=0.02), which were not observed at visit 5 (eos%: 0±1, p=0.9; basophil%: 0.2±0.2, p=0.8) (Table-1 ). Thus, clinical improvement among responders was independent of baseline disease severity. Non-responsiveness to benralizumab, measured by changes in UAS7, are likely due to other mechanistic factors unrelated to eos% which are eliminated by blocking IL-5R with benralizumab(S-Figure-1) .UAS7 and CU-QoLTS values were significantly correlated (r2=0.9, p<0.0001) (S-Table-3) . CU-QoL components that improved significantly were the pruritus/wheal scores, urticarial interference with physical activities, sleep and spare time (S-Table-4) .This study supports the use of benralizumab for treatment of SGAH-unresponsive CSU. Benralizumab-related improvements in UAS7 and CUQoLTS reported here are similar to the efficacy of omalizumab in CSU reported in a previous study (S-Table-5) .6The sustained significant improvement in urticarial lesions based on subject-reported outcomes by benralizumab warrants further investigation of underlying biologic pathways to better elucidate the role of IL-5 in CSU.

Although there is a considerable body of knowledge about allergen immunotherapy (AIT), there is a lack of data on the reliability of real-world evidence (RWE) in AIT and consequently, a lack of information on how AIT effectively works in real life. To address the current unmet need for an appraisal of the quality of RWE in AIT, the European Academy of Allergy and Clinical Immunology Methodology Committee recently initiated a systematic review of observational studies of AIT, which will use the RELEVANT tool and the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE) to rate the quality of the evidence base as a whole. The next step will be to develop a broadly applicable, pragmatic “real-world” database using systematic data collection. Based on the current RWE base, and perspectives and recommendations of authorities and scientific societies, a hierarchy of RWE in AIT is proposed, which places pragmatic trials and registry data at the positions of highest level of evidence. There is a need to establish more AIT registries that collect data in a cohesive way, using standardised protocols. This will provide an essential source of real-world data that can be easily shared, promoting evidence-based research and quality improvement in study design and clinical decision-making.

Background Essential training for emergency adrenaline auto-injector administration alone provides inadequate safeguard in school environments. Recent UK deaths have reinforced the urgency for embedding whole school (WS) allergy awareness to minimise risk. We document development of a practical, flexible WS Food Allergy Awareness Toolkit for UK secondary schools. Methods We used a multidisciplinary participatory action research methodology, involving successive modification and retesting of a pragmatic toolkit in 3 case study schools. A School Allergy Action Group drives WS risk assessment, helping schools gradually implement best practice policy in line with their particular needs. Additional schools self-piloted the resulting toolkit with only remote monitoring. School surveys, based on EAACI guidelines were developed to identify priorities and assess change. Results Effectiveness of the resulting process toolkit, now available online, was independently demonstrated via pre/post intervention questionnaires from 24/10 pupils with food allergy (FA) and 97/6 pupils without FA, respectively. Pearson correlational analysis showed strong negative relationships between Food Allergy Quality of Life Questionnaire (FAQLQ) at T0 and School Support (SS) at T0 (r=-0.8, p<0.01), and between SS and Self-Efficacy (SE) (r=0.73, p<0.05). Mean FAQLQ scores improved between T0 (3.3) and T1 (2.5). SE improved for those with FA (mean difference =1.0). In those without FA, SE (mean difference =0.9) and Attitudes and Knowledge (mean difference =0.7) also improved. Conclusions Full stakeholder involvement in toolkit development encourages usage and therefore improves WS community awareness; reduces risk of reactions; fosters a more accepting societal attitude; and empowers pupils with/without allergies to self-manage effectively.

Our understanding of IgE-mediated drug allergy relies on the hapten concept, which is well established in inducing reactions of the immune system to small molecules like drugs. The role of hapten-carrier adducts in re-challenge reactions leading to mast cell degranulation and anaphylaxis is unclear. Based on clinical observations, the speed of adduct formation, skin and in-vitro tests to inert drug molecules, a different explanation of IgE-mediated reactions to drugs is proposed: These are a) A natural role of reduced mast cell (MC) reactivity in developing IgE-mediated reactions to drugs. This MC-unresponsiveness is antigen-specific and covers the serum drug concentrations, but allows reactivity to locally higher concentrations. b) Some non-covalent drug-protein complexes rely on rather affine bindings and have a similar appearance as covalent hapten-carrier adducts. Such drug-protein complexes represent so-called “fake antigens”, as they are unable to induce immunity, but may react with and crosslink preformed drug-specific IgE. As they are formed very rapidly and in high concentrations, they may cause fulminant MC degranulation and anaphylaxis. c) The generation of covalent hapten-protein adducts requires hours, either because the formation of covalent bonds requires time or because first a metabolic step for forming a reactive metabolite is required. This slow process of stable adduct formation has the advantage that it may give time to desensitize mast cells, even in already sensitized individuals. The consequences of this new interpretation of IgE mediated reactions to drugs are potentially wide-reaching for IgE-mediated drug allergy but also allergy in general.

Background The prevalence of allergy to cat is expanding worldwide. Allergen-specific immunotherapy (AIT) has advantages over symptomatic pharmacotherapy and promises long lasting disease control in allergic patients. However, there is still a need to improve cat AIT regarding efficacy, safety and adherence to the treatment. Here we aim to boost immune tolerance to the major cat allergen Fel d 1 by increasing the anti-inflammatory activity of AIT with the established immunomodulatory adjuvant CpG, but at a higher dose than previously used in AIT. Methods Together with CpG, we used endotoxin-free Fel d 1 as therapeutic allergen throughout the study in a BALB/c model of allergy to Fel d 1, thus mimicking the conditions of human AIT trials. Multidimensional immune phenotyping including mass cytometry was applied to analyze AIT-specific immune signatures. Results We show that AIT with high-dose CpG in combination with endotoxin-free Fel d 1 reverts all major hallmarks of allergy. High dimensional CyTOF analysis of the immune cell signatures initiating and sustaining the AIT effect indicates the simultaneous engagement of both, the pDC-Treg and -B cell axis, with the emergence of a systemic GATA3+ FoxP3hi biTreg population. The regulatory immune signature also suggests the involvement of the anti-inflammatory TNF/TNFR2 signaling cascade in NK and B cells at an early stage and in Tregs later during AIT. Conclusion Our results highlight the potential of CpG adjuvant in a novel formulation to be further exploited for inducing allergen-specific tolerance in patients with cat allergy or other allergic diseases in the future.