Total IgE as a biomarker of omalizumab response in chronic spontaneous urticaria: A meta-analysis.

Omalizumab is approved for the treatment of chronic spontaneous urticaria (CSU) that is refractory to antihistamines. Total immunoglobulin E (IgE) levels have emerged as a possible biomarker to predict response to omalizumab. However, the existing literature is heterogenous, with conflicting conclusions with regard to the role of total IgE levels.

Alanine Scanning of the Unstructured Region of Ara h 2 and of a Related Mimotope Reveals Critical Amino Acids for IgE Binding.

Scope: The unstructured region of Ara h 2, referred to as epitope 3, contains a repeated motif, DYPSh (h = hydroxyproline) that is important for IgE binding.

Methods And Results: IgE binding assays to 20mer and shorter peptides of epitope 3, defines a 16mer core sequence containing one copy of the DPYSh motif, DEDSYERDPYShSQDP. This study performs alanine scanning of this and a related 12mer mimotope, LLDPYAhRAWTK.

IgE cross-inhibition between Ara h 1 and Ara h 2 is explained by complex formation of both major peanut allergens.

Background: Surprisingly, IgE cross-reactivity between the major peanut allergens Ara h 1, 2, and 3 has been reported despite very low sequence identities.

Objective: We investigated the unexpected cross-reactivity between peanut major allergens.

Methods: Cross-contamination of purified natural Ara h 1, 2, 3, and 6 was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot test, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and sandwich enzyme-linked immunosorbent assay (ELISA).

Structure and IgE Cross-Reactivity among Cashew, Pistachio, Walnut, and Peanut Vicilin-Buried Peptides.

Peanut and tree-nut allergies are frequently comorbid for reasons not completely understood. Vicilin-buried peptides (VBPs) are an emerging family of food allergens whose conserved structural fold could mediate peanut/tree-nut co-allergy. Peptide microarrays were used to identify immunoglobulin E (IgE) epitopes from the N-terminus of the vicilin allergens Ara h 1, Ana o 1, Jug r 2, and Pis v 3 using serum from three patient diagnosis groups: monoallergic to either peanuts or cashew/pistachio, or dual allergic.