Allergen protein binding to allergen-specific IgE antibodies triggers potentially fatal allergic reactions, such as peanut allergies. Researchers developed a nanoparticle-based assay to screen parts of allergenic peanut proteins, or epitopes, against IgE antibodies from 16 patients with peanut allergy.

The authors identified two epitopes capable of eliciting strong allergic reactions in serum samples from all or nearly all patients.

The authors engineered molecules called covalent heterobivalent inhibitors (cHBIs), designed to selectively and irreversibly bind to IgEs that recognize these two epitopes, thus permanently preventing the IgEs from binding to peanut proteins and triggering allergic reactions.

The cHBIs bound to IgE in serum from allergic patients more strongly than in control serum, and prevented allergen binding to patient IgE in vitro. Treatment with cHBIs inhibited more than 80% of the allergic response to crude peanut extract in serum samples from 14 of 16 patients, and significantly reduced basophil activation in whole blood from three individual patients.

The results suggest that cHBIs could form the basis of a therapeutic approach to allergies, according to the authors.

https://www.pnas.org/content/early/2019/04/02/1820417116