Indoor allergen levels in settled airborne dust are higher in day‐care centers than at home

355

357

There has been extensive progress in understanding the cellular and molecular mechanisms of inflammation and immune regulation in allergic diseases of the skin and lungs during the last few years. Asthma and atopic dermatitis (AD) are typical diseases of type 2 immune responses. interleukin (IL)-25, IL-33, and thymic stromal lymphopoietin are essential cytokines of epithelial cells that are activated by allergens, pollutants, viruses, bacteria, and toxins that derive type 2 responses. Th2 cells and innate lymphoid cells (ILC) produce and secrete type 2 cytokines such as IL-4, IL-5, IL-9, and IL-13. IL-4 and IL-13 activate B cells to class-switch to IgE and also play a role in T-cell and eosinophil migration to allergic inflammatory tissues. IL-13 contributes to maturation, activation, nitric oxide production and differentiation of epithelia, production of mucus as well as smooth muscle contraction, and extracellular matrix generation. IL-4 and IL-13 open tight junction barrier and cause barrier leakiness in the skin and lungs. IL-5 acts on activation, recruitment, and survival of eosinophils. IL-9 contributes to general allergic phenotype by enhancing all of the aspects, such as IgE and eosinophilia. Type 2 ILC contribute to inflammation in AD and asthma by enhancing the activity of Th2 cells, eosinophils, and their cytokines. Currently, five biologics are licensed to suppress type 2 inflammation via IgE, IL-5 and | 1583 AKDIS et Al. 1 | INTRODUC TI ON Allergic diseases cause significant morbidity and mortality with almost one billion cases, accounting for a significant portion of overall healthcare costs. The dysregulated immune response, chronic inflammation, and remodeling in the affected tissues define a dynamic and heterogeneous spectrum of anaphylaxis, food allergy, asthma, allergic rhinitis, chronic rhinosinusitis with nasal polyposis (CRSwNP), and atopic dermatitis (AD). Two main subtypes of immune responses driving asthma and AD have been defined, namely type 2-high and type 2-low. 1-4 Precision medicine and biomarker discovery is important for the management of asthma and AD in the context of a better selection of good responders to treatment, prediction of outcomes, and design of disease-modifying strategies. Progress has been made in profiling the type 2 immune response-driven diseases. In contrast, the non-type 2 immune response in asthma and AD is insufficiently understood. The majority of patients with AD, CRS and asthma involve, or result from, an overexpression of type 2 inflammatory pathways (Figure 1). 5-7 A specific type 2 set of cytokines are produced during the induction and maintenance of allergic immune response with the contribution of epithelial cells, dendritic cells (DC), T cells, innate lymphoid cells (ILC), eosinophils, mast cells (MC), and basophils. Activation of Th2 and ILC2 pathways is at the core of type 2 inflammation. Th2 cytokines include interleukin (IL)-4, IL-5, IL-9, IL-13, and IL-31, and main type 2 cytokines of ILC2 are IL-5, IL-9, and IL-13. 8,9 IL-4 induces Th2 cell di...

Section: Type 2 Immunity In the Lung And Skinmentioning

confidence: 99%

Type 2 immunity in the skin and lungs

Akdiş

Arkwright

Brüggen

et al. 2020

355

357

Section: Other Sources Of Indoor Air Pollutionmentioning

confidence: 99%

“…63 In addition to residential environments, indoor air quality in nonresidential buildings (e.g., schools) plays an important role in respiratory health. [64][65][66] The Schools Indoor Pollution and Health: Observatory Network in Europe (SINPHONIE) project, funded by the European Parliament, assessed indoor air exposure in schools in 23 countries. 67 The study found that PM 2.5 , some VOCs (e.g., formaldehyde), radon, and allergens (especially molds) were commonly present.…”

Section: (B) (B) (C) (A)mentioning

confidence: 99%

The need for clean air: The way air pollution and climate change affect allergic rhinitis and asthma

Eguiluz‐Gracia

Mathioudakis

Bartel

et al. 2020

282

193

Air pollution and climate change have a significant impact on human health and well‐being and contribute to the onset and aggravation of allergic rhinitis and asthma among other chronic respiratory diseases. In Westernized countries, households have experienced a process of increasing insulation and individuals tend to spend most of their time indoors. These sequelae implicate a high exposure to indoor allergens (house dust mites, pets, molds, etc), tobacco smoke, and other pollutants, which have an impact on respiratory health. Outdoor air pollution derived from traffic and other human activities not only has a direct negative effect on human health but also enhances the allergenicity of some plants and contributes to global warming. Climate change modifies the availability and distribution of plant‐ and fungal‐derived allergens and increases the frequency of extreme climate events. This review summarizes the effects of indoor air pollution, outdoor air pollution, and subsequent climate change on asthma and allergic rhinitis in children and adults and addresses the policy adjustments and lifestyle changes required to mitigate their deleterious effects.

“…2 9 It is passively transferred on clothing 2,5,19 ; as a result, the allergen is ubiquitous and has been documented in homes without cats, private vehicles, and public transportation and buildings at levels (≥8 µg Fel d 1 per gram of dust) that exceed threshold value associated with sensitization. 2,5,7,[25][26][27][28][29][30][31][32][33][34] Although Fel d 1 levels in schools are detectable, they are often low and may not induce symptoms, 35 but a Swedish study found that indirect exposure to cat may be associated with worsening of asthma in cat-allergic students. 26…”

Section: Fel D1 the Ma Jor C At Allerg Enmentioning

confidence: 99%

Keep the cat, change the care pathway: A transformational approach to managing Fel d 1, the major cat allergen

Satyaraj¹,

Wedner

Bousquet

2019

Background Allergies to cats are the most common animal‐origin allergy, and affect approximately 1 in 5 adults worldwide. The prevalence of allergy to furry animals has been increasing, and allergy to cats is a major risk factor for the development of asthma and rhinitis. The diagnosis of cat allergy is now well established. The exact significance of component‐resolved diagnosis in the diagnosis of cat allergy remains to be fully understood. Allergen avoidance is effective but often has a psychologic impact. Allergen immunotherapy is not well demonstrated. There is a need for innovative approaches to better manage cat allergens. Next‐generation care pathways for asthma and rhinitis will define the place of cat allergen avoidance. Methods and Results This manuscript, based on content presented at the European Academy of Allergy and Clinical Immunology Congress 2019, provides information on the prevalence and impact of cat allergies and the molecular biology of Fel d 1, the major cat allergen. Discussion The authors present the scientific basis of a novel care pathway that utilizes anti‐Fel d 1 IgY antibodies to safely and effectively neutralize Fel d 1 after its production by the cat but before human exposure. Conclusion Efficacy of a feline diet with an egg product ingredient containing anti‐Fel d 1 IgY antibodies was demonstrated in vitro, ex vivo, and in vivo, and further validated by a pilot exposure study involving cat‐allergic human participants.