Publications by authors named "Janice A Layhadi"

Background: Peanut allergy (PA) is one of the most prevalent food allergies with a lack of favorable safety/efficacy treatment. A cucumber mosaic virus-like particle expressing peanut allergen component Ara h 2 (VLP Peanut) has been developed as a novel therapeutic approach for PA.

Objective: We assessed the tolerogenic properties and reactivity of VLP Peanut.

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Background: During the COVID-19 pandemic, novel nanoparticle-based mRNA vaccines were developed. A small number of individuals developed allergic reactions to these vaccines although the mechanisms remain undefined.

Methods: To understand COVID-19 vaccine-mediated allergic reactions, we enrolled 19 participants who developed allergic events within 2 h of vaccination and 13 controls, nonreactors.

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Background: Local allergic rhinitis (LAR) is defined by chronic nasal symptoms, absence of atopy, positive nasal allergen challenge (NAC) and a good response to subcutaneous allergen immunotherapy (SCIT). We sought to investigate SCIT capacity to induce local and systemic blocking antibodies in LAR patients.

Methods: A RDBPC study of grass SCIT was performed, with participants receiving either SCIT (Group A; n = 10) or placebo (Group B; n = 14) in the first 6 months.

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Article Synopsis
  • Genetic and environmental factors can disrupt the epithelial barrier, leading to a T2 inflammatory response, so protecting this barrier is key to reducing the risk of atopic diseases like food allergies.
  • The review highlights structural aspects of the epithelial barrier in atopic dermatitis patients, including filaggrin gene mutations, the role of transient receptor potential vanilloid 1, and the microbiome's impact on skin health.
  • It also covers both traditional and innovative therapies aimed at enhancing the skin barrier, such as moisturizers, topical treatments, probiotics, and emerging strategies like epicutaneous immunotherapy and gene therapy to prevent and treat food allergies.
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T and B cells are key components of the adaptive immune system. Through their immune properties and their interactions with other immune cells and cytokines around them, they build a complex network to achieve immune tolerance and maintain homeostasis of the body. This is achieved through mechanisms of central and peripheral tolerance, both of which are associated with advantages and disadvantages.

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Allergen immunotherapy (AIT) remains to be the only disease-modifying treatment for IgE-mediated allergic diseases such as allergic rhinitis. It can provide long-term clinical benefits when given for 3 years or longer. Mechanisms of immune tolerance induction by AIT are underscored by the modulation of several compartments within the immune system.

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Background: Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these immunotherapeutic vaccine products. Novel single-cell RNA sequencing technology offers a bridge to this gap in knowledge.

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Background: Mechanisms causing the onset and perpetuation of inflammation in severe allergic patients remain unknown. Our previous studies suggested that severe allergic inflammation is linked to platelet dysfunction.

Methods: Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) samples were obtained by platelet-apheresis from severe (n = 7) and mild (n = 10) allergic patients and nonallergic subjects (n = 9) to perform platelet lipidomics by liquid chromatography coupled to mass spectrometry (LC-MS) and RNA-seq analysis.

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Allergic rhinitis is an IgE-mediated inflammation that remains a clinical challenge, affecting 40% of the UK population with a wide range of severity from nasal discomfort to life-threatening anaphylaxis. It can be managed by pharmacotherapeutics and in selected patients by allergen immunotherapy (AIT), which provides long-term clinical efficacy, especially during peak allergy season. However, there are no definitive biomarkers for AIT efficacy.

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Background: Unsupervised clustering of biomarkers derived from noninvasive samples such as nasal fluid is less evaluated as a tool for describing asthma endotypes.

Objective: We sought to evaluate whether protein expression in nasal fluid would identify distinct clusters of patients with asthma with specific lower airway molecular phenotypes.

Methods: Unsupervised clustering of 168 nasal inflammatory and immune proteins and Shapley values was used to stratify 43 patients with severe asthma (endotype of noneosinophilic asthma) using a 2 "modeling blocks" machine learning approach.

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There are currently no biomarkers that can accurately predict clinical outcomes and segregate responders from nonresponders in allergen immunotherapy (AIT). Therefore, identifying a reliable predictive biomarker is essential to enable clinicians to tailor personalized therapy. New developments in AIT biomarkers are currently being explored, and it would be important to identify key areas of development and their feasibility for use in the clinic.

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Allergen immunotherapy (AIT) is an effective treatment for allergic rhinitis, inducing long-term clinical tolerance to the sensitizing allergen. Clinical tolerance induction can be achieved when AIT is administered for at least 3 years. AIT is associated with the modulation of innate and adaptive immune systems.

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Introduction: There is no detailed comparison of allergen-specific immunoglobulin responses following sublingual immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT).

Objective: We sought to compare nasal and systemic timothy grass pollen (TGP)-specific antibody responses during 2 years of SCIT and SLIT and 1 year after treatment discontinuation in a double-blind, double-dummy, placebo-controlled trial.

Methods: Nasal fluid and serum were obtained yearly (per-protocol population, n = 84).

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Long-term efficacy that occurs with allergen immunotherapy of proven value is associated with decreases in IgE-dependent activation of mast cells and tissue eosinophilia. This suppression of type 2 immunity is accompanied by early induction of regulatory T cells, immune deviation in favor of T1 responses, and induction of local and systemic IgG, IgG, and IgA antibodies. These "protective" antibodies can inhibit allergen-IgE complex formation and consequent mast cell triggering and IgE-facilitated T2-cell activation.

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Sensitization to Fel d 1 ( allergen 1) contributes to persistent allergic rhinitis and asthma. Existing treatment options for cat allergy, including allergen immunotherapy, are only moderately effective, and allergen immunotherapy has limited use because of safety concerns. To explore the relationship among the pharmacokinetic, clinical, and immunological effects of anti-Fel d 1 monoclonal antibodies (REGN1908-1909) in patients after treatment.

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Food allergy is an increasingly prevalent disease driven by uncontrolled type 2 immune response. Currently, knowledge about the underlying mechanisms that initiate and promote the immune response to dietary allergens is limited. Patients with food allergy are commonly sensitized through the skin in their early life, later on developing allergy symptoms within the gastrointestinal tract.

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The role of innate immune cells in allergen immunotherapy that confers immune tolerance to the sensitizing allergen is unclear. Here, we report a role of interleukin-10-producing type 2 innate lymphoid cells (IL-10 ILC2s) in modulating grass-pollen allergy. We demonstrate that KLRG1 but not KLRG1 ILC2 produced IL-10 upon activation with IL-33 and retinoic acid.

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Purpose Of Review: Allergic rhinitis (AR) is a chronic inflammatory immunoglobulin (Ig) E-mediated disease of the nasal mucosa that can be triggered by the inhalation of seasonal or perennial allergens. Typical symptoms include sneezing, rhinorrhea, nasal itching, nasal congestion and symptoms of allergic conjunctivitis. AR affects a quarter of the population in the United States of America and Europe.

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Allergen immunotherapy is a cornerstone in the treatment of allergic children. The clinical efficiency relies on a well-defined immunologic mechanism promoting regulatory T cells and downplaying the immune response induced by allergens. Clinical indications have been well documented for respiratory allergy in the presence of rhinitis and/or allergic asthma, to pollens and dust mites.

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Background: IgE is the least abundant immunoglobulin and tightly regulated, and IgE-producing B cells are rare. The cellular origin and evolution of IgE responses are poorly understood.

Objective: The cellular and clonal origin of IgE memory responses following mucosal allergen exposure by sublingual immunotherapy (SLIT) were investigated.

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