Basophil Activation Test Reduces Oral Food Challenges to Nuts and Sesame.

Background: Nut allergic patients are often IgE sensitized to other nuts/seeds and need multiple oral food challenges (OFCs) before the safe nuts can be introduced in the diet. However, OFCs are time-consuming and risky procedures.

Objective: To assess the utility of the basophil activation test (BAT) to predict the allergic status and reduce the need for an OFC in children with 1 or more nut or seed allergies.

Biomarkers of severity and threshold of allergic reactions during oral peanut challenges.

Background: Oral food challenge (OFC) is the criterion standard to assess peanut allergy (PA), but it involves a risk of allergic reactions of unpredictable severity.

Objective: Our aim was to identify biomarkers for risk of severe reactions or low dose threshold during OFC to peanut.

Methods: We assessed Learning Early about Peanut Allergy study, Persistance of Oral Tolerance to Peanut study, and Peanut Allergy Sensitization study participants by administering the basophil activation test (BAT) and the skin prick test (SPT) and measuring the levels of peanut-specific IgE, Arachis hypogaea 2-specific IgE, and peanut-specific IgG4, and we analyzed the utility of the different biomarkers in relation to PA status, severity, and threshold dose of allergic reactions to peanut during OFC.

Nasal allergen-neutralizing IgG antibodies block IgE-mediated responses: Novel biomarker of subcutaneous grass pollen immunotherapy.

Background: Grass pollen subcutaneous immunotherapy (SCIT) is associated with induction of serum IgG-associated inhibitory antibodies that prevent IgE-facilitated allergen binding to B cells.

Objective: We sought to determine whether SCIT induces nasal allergen-specific IgG antibodies with inhibitory activity that correlates closely with clinical response.

Methods: In a cross-sectional controlled study, nasal fluid and sera were collected during the grass pollen season from 10 SCIT-treated patients, 13 untreated allergic patients (with seasonal allergic rhinitis [SAR]), and 12 nonatopic control subjects.

Role of IL-35 in sublingual allergen immunotherapy.

Background: Grass pollen-specific immunotherapy involves immunomodulation of allergen-specific T2 responses and induction of IL-10 and/or TGF-βCD4CD25 regulatory T cells (induced Treg cells). IL-35CD4CD25 forkhead box protein 3-negative T (IL-35-inducible regulatory T [iT35]) cells have been reported as a novel subset of induced Treg cells with modulatory characteristics.

Objective: We sought to investigate mechanisms underlying the induction and maintenance of immunologic tolerance induced by IL-35 and iT35 cells.

IgG4 inhibits peanut-induced basophil and mast cell activation in peanut-tolerant children sensitized to peanut major allergens.

Background: Most children with detectable peanut-specific IgE (P-sIgE) are not allergic to peanut. We addressed 2 non-mutually exclusive hypotheses for the discrepancy between allergy and sensitization: (1) differences in P-sIgE levels between children with peanut allergy (PA) and peanut-sensitized but tolerant (PS) children and (2) the presence of an IgE inhibitor, such as peanut-specific IgG4 (P-sIgG4), in PS patients.

Methods: Two hundred twenty-eight children (108 patients with PA, 77 PS patients, and 43 nonsensitized nonallergic subjects) were studied.