Mapping the Interactions between a Major Pollen Allergen and Human IgE Antibodies

SummaryThe interaction of specific IgE antibodies with allergens is a key event in the induction of allergic symptoms, thus representing an important target for therapeutic interventions in Type I allergies. We report here the solution NMR structure of Art v 1, the major mugwort pollen allergen. Art v 1 is the first protein structure with an allergenic defensin fold linked to a polyproline domain, which has not been identified in any reported allergen structure in the PDB. Moreover, the direct interaction of polyclonal IgE antibodies from an allergic patient has been mapped on the surface of an allergen for the first time. The data presented herein provide the basis for the design of tools for safe and effective vaccination against mugwort pollen allergy.

► Art v 1 displays a cysteine stabilized defensin fold linked to a polyproline region
► The proline region consists of a structured part and a flexible C terminus
► Residues interacting with human IgE Abs form two patches on the defensin domain
► Epitope patches are positively charged and conserved among allergenic defensins