Figure 6. Allergome of the birch pollen major allergen Bet v 1 (3D structure in the center). Structural similarity (arrows) between Bet v 1 and similar PR-10 proteins in other tree pollen, fruits, and vegetables as a reason for birch pollen-associated cross-allergy, which is frequent in Central Europe (modified based on an O-ring of Bet v 1; dynamically generated in www.allergome.org; 3D-structure of Bet v 1 from www.ebi.ac.uk/pdbe-srv/view/entry/1btv/summary.html).