Experimental food allergy to peanut enhances the immune response to house dust mite in the airways of mice

Food allergy promotes a Th2/Th17 response that drives house dust mite-induced allergic airway inflammation in humanized mice

Food allergy is related to increasing risk of the development of allergic asthma, but the precise interplay between sensitization to different allergens in different compartments of the body is not fully understood. The aim of this study was to develop a novel humanized murine model of mixed food and respiratory allergy that recapitulates the human anaphylactic response and to more clearly understand the impact of food allergies on asthma. Immunodeficient mice transferred with peripheral blood mononuclear cells (PBMCs) from donors with peanut and house dust mite (HDM) allergy were exposed and challenged to peanut. Between peanut exposure and challenge, mice were intranasally treated to HDM. Allergic parameters were analyzed. Allergen-specific immunoglobulin (Ig)E in sera could only be measured in mice treated with peripheral blood mononuclear cells (PBMCs) plus allergen. A preceding peanut exposure increased IgE levels, histamine release, bronchial hyper-responsiveness and lung inflammation. Recruitment of inflammatory cells to the airways was aggravated associated with an enhanced T helper type 2 (Th2)/Th17 cytokine secretion when the two allergies were present. A preceding peanut exposure amplifies allergic asthma in this humanized model, which may contribute to the understanding of underlying immunological mechanism of polysensitization occurring in allergic individuals and evaluation of therapeutic interventions.

Developments in the field of allergy in 2017 through the eyes of Clinical and Experimental Allergy

In this article, we described the development in the field of allergy as described by Clinical and Experimental Allergy in 2017. Experimental models of allergic disease, basic mechanisms, clinical mechanisms, allergens, asthma and rhinitis and clinical allergy are all covered.

Kininogen deficiency or depletion reduces enhanced pause independent of pulmonary inflammation in a house dust mite-induced murine asthma model

High-molecular-weight kininogen is an important substrate of the kallikrein-kinin system. Activation of this system has been associated with aggravation of hallmark features in asthma. We aimed to determine the role of kininogen in enhanced pause (Penh) measurements and lung inflammation in a house dust mite (HDM)-induced murine asthma model. Normal wild-type mice and mice with a genetic deficiency of kininogen were subjected to repeated HDM exposure (sensitization on days 0, 1, and 2; challenge on days 14, 15, 18, and 19) via the airways to induce allergic lung inflammation. Alternatively, kininogen was depleted after HDM sensitization by twice-weekly injections of a specific antisense oligonucleotide (kininogen ASO) starting at day 3. In kininogen-deficient mice HDM induced in Penh was completely prevented. Remarkably, kininogen deficiency did not modify HDM-induced eosinophil/neutrophil influx, T helper 2 responses, mucus production, or lung pathology. kininogen ASO treatment started after HDM sensitization reduced plasma kininogen levels by 75% and reproduced the phenotype of kininogen deficiency: kininogen ASO administration prevented the HDM-induced increase in Penh without influencing leukocyte influx, Th2 responses, mucus production, or lung pathology. This study suggests that kininogen could contribute to HDM-induced rise in Penh independently of allergic lung inflammation. Further research is warranted to confirm these data using invasive measurements of airway responsiveness.