No abstract

Although Blo t 10 and Der p 10 are highly conserved (shared 95% amino acids identity) and significantly cross-reactive, unique IgE epitopes do exist. The results suggest the potential deficiency of using only one of these highly conserved allergens as diagnostic or therapeutic reagents.

The results indicate that compared with public places, the home consitutes a major reservior of indoor allergens. Allergens of the storage mite, B. tropicalis, should be considered as a major allergenic component of dust in Singapore.

Blo t 5 is the major allergen from Blomia tropicalis mites and shows strong IgE reactivity with up to 90% of asthmatic and rhinitis patients' sera. The NMR solution structure of Blo t 5 comprises three long alpha helices, forming a coiled-coil, triple-helical bundle with a left-handed twist. TROSY-NMR experiments were used to study Blo t 5 interaction with the Fab' of a specific monoclonal antibody, mAb 4A7. The mAb epitope comprises two closely spaced surfaces, I and II, connected by a sharp turn and bearing critical residues Asn46 and Lys47 on one surface, and Lys54 and Arg57 on the other. This discontinuous epitope overlaps with the human IgE epitope(s) of Blo t 5. Epitope surface II is further predicted to undergo conformational exchange in the millisecond to microsecond range. The results presented are critical for the design of a hypoallergenic Blo t 5 for efficacious immunotherapy of allergic diseases.

The results indicate that compared with public places, the home consitutes a major reservior of indoor allergens. Allergens of the storage mite, B. tropicalis, should be considered as a major allergenic component of dust in Singapore.