Structural and Epitope Characterization of Major Allergens from Dust Mite, BLO T 21 and DER F 7

Abstract

House dust mites are recognized as a major cause of allergic diseases worldwide. Here, we present the 3D structures and immuno-characterization of Blo t 21 and Der f 7, two major allergens from house dust mites. The NMR structure of Blo t 21 resembles that of its paralogue, Blo t 5. The immunological studies showed that Blo t 21 could have a unique conformational epitope, and a different linear epitope compared to that of Blo t 5, thus explaining their limited cross-reactivity. The crystal structure of Der f 7 is very similar to its homologue, Der p 7. Residues L48 and F50 should be the IgE epitopes of Der f 7 but residue D159 is unlikely to be responsible for its cross-reactivity with Der p 7 as reported previously. Both allergens show unique immunological properties and therefore should be considered for the future development of immunotherapy.