Publications by authors named "Toshiro Takai"

Respiratory allergen sources such as house dust mites frequently contain proteases. In this study, we demonstrated that the epicutaneous application of a model protease antigen, papain, onto intact or tape-stripped ear skin of mice induced acute scratching behaviors and T helper (Th)2, Th9, Th17/Th22, and/or Th1 sensitization in a protease activity-dependent manner. The protease activity of papain applied onto the skin was also essential for subsequent airway eosinophilia induced by an intranasal challenge with low-dose papain.

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Introduction: Repeated skin contact to detergents causes chronic irritant contact dermatitis (ICD) associated with itch sensation and eczema. However, the mechanisms of detergent-induced ICD are poorly understood. Here, we established a new murine model of detergent-induced ICD with H1-antihistamine-refractory itch.

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Epicutaneous exposure to allergenic proteins is an important sensitization route for skin diseases like protein contact dermatitis, immunologic contact urticaria, and atopic dermatitis. Environmental allergen sources such as house dust mites contain proteases, which are frequent allergens themselves. Here, the dependency of T-helper (T) cell recall responses on allergen protease activity in the elicitation phase in mice pre-sensitized via distant skin was investigated.

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Article Synopsis
  • Epicutaneous (e.c.) allergen exposure plays a crucial role in developing allergic diseases, and proteases in allergens, like those from house dust mites, contribute to this process while being regulated by prostanoids from cyclooxygenase (COX) pathways.
  • In an experiment with mice, treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) during e.c. sensitization to a protease allergen, papain, showed increased immune responses, including higher IgE levels and cytokine production linked to allergic reactions.
  • The study concludes that COX-derived prostanoids have a suppressive effect on the immune response, particularly on Th2 and Th17 cells, suggesting that inhibiting COX pathways
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Environmental allergen sources such as house dust mites contain proteases, which are frequently allergens themselves. Inhalation with the exogenous proteases, such as a model of protease allergen, papain, to airways evokes release and activation of IL-33, which promotes innate and adaptive allergic airway inflammation and Th2 sensitization in mice. Here, we examine whether epicutaneous (e.

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IL-33-activated group 2 innate lymphoid cells critically contribute to protease allergen-induced airway inflammation models. However, IL-33 is dispensable for a subcutaneous (s.c.

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Protease activity of papain, a plant-derived occupational allergen homologous to mite major allergens, is essential to IgE/IgG1 production and lung eosinophilia induced by intranasal papain administration in mice, and IL-33 contributes to these responses. In this work, we investigate skin and Ab responses induced by s.c.

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Allergen sources such as mites, insects, fungi, and pollen contain proteases. Airway exposure to proteases induces allergic airway inflammation and IgE/IgG1 responses via IL-33-dependent mechanisms in mice. We examined the epicutaneous sensitization of mice to a model protease allergen, papain; the effects of tape stripping, which induces epidermal barrier dysfunction; and the atopic march upon a subsequent airway challenge.

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Background: Patients with house dust mite (HDM) allergy or Ascariasis produce serum IgE specific to the antigens of HDM or nematode Ascaris, respectively. Although human IgE cross-reactivity has been reported between HDM and Ascaris antigens, it remains unclear whether it contributes to the pathogenesis of allergic diseases. We herein investigated the induction of cross-reactive antibodies and T cells in mice and effects of airway exposure to HDM antigens after preimmunization with Ascaris antigens.

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Background: Pollen released by allergenic members of the botanically unrelated families of Asteraceae and Cupressaceae represent potent elicitors of respiratory allergies in regions where these plants are present. As main allergen sources the Asteraceae species ragweed and mugwort, as well as the Cupressaceae species, cypress, mountain cedar, and Japanese cedar have been identified. The major allergens of all species belong to the pectate lyase enzyme family.

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Background: In the 1990s, the Japanese Society of Allergology (JSA) standardized Japanese cedar pollen allergen vaccines. In the present study, the task force for house dust mite (HDM) allergen standardization of the Committee for Allergens and Immunotherapy of JSA reports the standardization of HDM allergen vaccines in Japan.

Methods: In vivo allergenic potency was determined by intradermal testing of 51 Japanese adults with positive serum specific IgE to HDM allergens.

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Th2 type immune responses are essential for protective immunity against parasites and play crucial roles in allergic disorders. Helminth parasites secrete a variety of proteases for their infectious cycles including for host entry, tissue migration, and suppression of host immune effector cell function. Furthermore, a number of pathogen-derived antigens, as well as allergens such as papain, belong to the family of cysteine proteases.

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Background: In the 1990s, the Japanese Society of Allergology (JSA) standardized Japanese cedar pollen allergen vaccines. In the present study, the task force for house dust mite (HDM) allergen standardization of the Committee for Allergens and Immunotherapy of JSA reports the standardization of HDM allergen vaccines in Japan.

Methods: In vivo allergenic potency was determined by intradermal testing of 51 Japanese adults with positive serum specific IgE to HDM allergens.

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The sublingual mucosa (SLM) is utilized as the site for sublingual immunotherapy (SLIT) to induce tolerance against allergens. The contribution of SLM-dendritic cells (SLM-DCs) has not been clarified. The aim of this study was to examine the dynamics and phenotype of SLM-DCs after topical antigen painting and SLIT.

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Background: Epicutaneous sensitization to allergens is important in the pathogenesis of not only skin inflammation such as atopic dermatitis but also "atopic march" in allergic diseases such as asthma and food allergies. We here examined antibody production and skin barrier dysfunction in mice epicutaneously administered papain, a plant-derived occupational allergen belonging to the same family of cysteine proteases as mite major group 1 allergens.

Methods: Papain and Staphylococcus aureus V8 protease were patched on the backs of hairless mice.

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