International consensus (ICON) on: clinical consequences of mite hypersensitivity, a global problem

Abstract

Since mite allergens are the most relevant inducers of allergic diseases worldwide, resulting in significant morbidity and increased burden on health services, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), the European Academy of Allergy and Clinical Immunology (EAACI), and the World Allergy Organization (WAO), has proposed to issue an International Consensus (ICON) on the clinical consequences of mite hypersensitivity. The objectives of this document are to highlight aspects of mite biology that are clinically relevant, to update the current knowledge on mite allergens, routes of sensitization, the genetics of IgE responses to mites, the epidemiologic aspects of mite hypersensitivity, the clinical pictures induced by mites, the diagnosis, specific immunotherapeutic approaches, and prevention.

Fig. 1

Taxonomy of Mites with Allergenic Relevance

Fig. 2

X-ray crystal structure of Der p 1 in complex with Fab fragments of three anti-Der p 1 monoclonal antibodies, 5H8, 10B9, and 4C1. Reproduced from: Tomasz Osinski, Anna Pomés, Karolina A. Majorek, Jill Glesner, Lesa R. Offermann, Lisa D. Vailes, Martin D. Chapman, Wladek Minor, Maksymilian Chruszcz. Structural analysis of Der p 1-antibody complexes and comparison with complexes of proteins or peptides with monoclonal antibodies. J Immunol 2015; 195: 307–316. DOI: 10.4049/jimmunol.1402199. Figure 1 reused with permission. Copyright 2015. The American Association of Immunologists, Inc

Fig. 3

Simplified model of the HDM-induced innate immune activation leading to IgE sensitization in the airways. The induction ofTh2 immunity by HDM allergens results from the stimulation of different innate immune pathways. HDM protease allergens specifically cleave protease sensitive receptors including protease-activated receptor (PAR)-2, disrupt epithelial barrier to gain access to dendritic cells (DCs), and cause tissue injuries to release danger-associated molecular patterns (DAMPs) such as adenosine triphosphate (ATP) and uric acid. Contaminating microbial pathogen-associated molecular patterns (PAMPs) associated or not with lipid-binding allergens trigger numerous pathogen recognition receptors (PRRs) which can produce also DAMPs whereas HDM glycan activation of DCs is mediated through C-type lectin receptors (CLR) ligation. These signaling pathways result in the upregulation of innate cytokines/chemokines such as IL-1β, IL-6, thymocyte stromal lymphpoetin (TSLP), IL-25, IL-33, GM-CSF, or CCL20 to recruit and activate inflammatory cells and to induce Th2 differentiation. TSLP mediates OX40L and IL-4 expression in DCs and basophils, respectively, to initiate a Th2-polarized response. IL-25 and IL-33 are strong activators of innate lymphocyte cells (ILC2s) which secrete theTh2 cytokine IL-13 to induce IgE secretion by B cells [40]. Modified from: Alain Jacquet, Innate immune responses in house dust mite allergy. IRSN Allergy 2013; 2013: 735031. DOI: 10.1155/2013/735031. The authors used Fig. 2 under the Creative Commons Attribution License

Fig. 4

Allergen Immunotherapy for HDM-induced Rhinitis. Adapted from: Moisés A. Calderón, Jörg Kleine-Tebbe, Allan Linneberg, Frédéric De Blay, Dolores Hernandez Fernandez de Rojas, Johann Christian Virchow, Pascal Demoly. House Dust Mite Respiratory Allergy: An Overview of Current Therapeutic Strategies The Journal of Allergy and Clinical Immunology: In Practice 2015; 3(6): 843–855. http://dx.doi.org/10.1016/j.jaip.2015.06.019. Adapted under the Open Access Creative Commons License. The authors have used Fig. 3a, Immunotherapy. Calderon MA et al. J Allergy Clin Immunol In Practice 2015; 3: 843-55. ¹Calderon MA et al. Cochrane Database of Systematic Reviews 2013. No.: CD007163[In prees]. ²Radulovic S et al. Cochrane Database Syst Rev. 2010 Dec. 8:(12):CD002893

Fig. 5

Allergen Immunotherapy for HDM-induced Asthma. Adapted from: Moisés A. Calderón, Jörg Kleine-Tebbe, Allan Linneberg, Frédéric De Blay, Dolores Hernandez Fernandez de Rojas, Johann Christian Virchow, Pascal Demoly. House Dust Mite Respiratory Allergy: An Overview of Current Therapeutic Strategies. The Journal of Allergy and Clinical Immunology: In Practice 2015; 3(6): 843–855. http://dx.doi.org/10.1016/j.jaip.2015.06.019. Adapted under the Open Access Creative Commons License. The `s have used Fig. 3b, Immunotherapy. Calderon MA et al. J Allergy Clin Immunol In Practice 2015; 3: 843-55. ¹Abramson MJ et al. Cochrane Database Syts Rev. 2010 Aug 4: (8): CD001186. ²Calamita Z et al. Allergy 2008 ; 62: 1162-72