Although a large number of allergens have been characterized, it is not know how such diverse structures could all lead to the stimulation of T cell helper type 2 responses and subsequent bias towards the synthesis of IgE. In July Molecular Pathology, Furmonaviciene and Shakib from the University of Nottingham, UK show that various allergens have a common structural motif, which could potentially explain their ability to elicit powerful IgE antibody responses.
Furmonaviciene and Shakib analyzed the three dimensional structures and examined multiple sequence alignments of diverse allergens such as the plant cysteine protease papain, the transport protein lipocalin Mus m 1 and the ragweed allergen Amb a 5. They found that these allergens have a similar structural motif; namely, an α–β groove resembling the substrate binding groove of house dust mite allergen Der p 1. The groove is located inside a β motif, between a helix on one...