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A native IgE in complex with profilin provides insights into allergen recognition and cross-reactivity.

ABSTRACT: Allergies have become a rising health problem, where plentiful substances can trigger IgE-mediated allergies in humans. While profilins are considered minor allergens, these ubiquitous proteins are primary molecules involved in cross-reactivity and pollen-food allergy syndrome. Here we report the first crystal structures of murine Fab/IgE, with its chains naturally paired, in complex with the allergen profilin from Hevea brasiliensis (Hev b 8). The crystallographic models revealed that the IgE's six complementarity-determining regions (CDRs) interact with the allergen, comprising a rigid paratope-epitope surface of 926 Å², which includes an extensive network of interactions. Interestingly, we also observed previously unreported flexibility at Fab/IgE's elbow angle, which did not influence the shape of the paratope. The Fab/IgE exhibits a high affinity for Hev b 8, even when using 1 M NaCl in BLI experiments. Finally, based on the encouraging cross-reactivity assays using two mutants of the maize profilin (Zea m 12), this antibody could be a promising tool in IgE engineering for diagnosis and research applications.

SUBMITTER: Garcia-Ramirez B

PROVIDER: S-EPMC9334453 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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A native IgE in complex with profilin provides insights into allergen recognition and cross-reactivity.

García-Ramírez Benjamín B Mares-Mejía Israel I Rodríguez-Hernández Annia A Cano-Sánchez Patricia P Torres-Larios Alfredo A Ortega Enrique E Rodríguez-Romero Adela A

Communications biology 20220727 1

Allergies have become a rising health problem, where plentiful substances can trigger IgE-mediated allergies in humans. While profilins are considered minor allergens, these ubiquitous proteins are primary molecules involved in cross-reactivity and pollen-food allergy syndrome. Here we report the first crystal structures of murine Fab/IgE, with its chains naturally paired, in complex with the allergen profilin from Hevea brasiliensis (Hev b 8). The crystallographic models revealed that the IgE's ...[more]

PMID: 35902770

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A native IgE in complex with profilin provides insights into allergen recognition and cross-reactivity.

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A native IgE in complex with profilin provides insights into allergen recognition and cross-reactivity.

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