Characterization of a new subtype of allergen in dermatophagoides farinae-Der f 28.

BACKGROUND:House dust mites (HDMs) are the major sources of indoor allergens which induce asthma, dermatitis, rhinitis, and some other allergic diseases. Close to 30 sub-allergens have been identified. METHODS:Through analyzing the full genome sequence of dust mite, a new allergen whose primary structure belongs to the heat shock protein family was identified. The sequence of this allergen was determined by cDNA cloning. The allergenicity was assayed by skin prick test, Western-blot and enzyme-linked immunosorbent assay (ELISA). RESULTS:r-Der f 28 bound to serum IgE from mite allergic patients. Positive responses to r-Der f 28 were shown in 11.5% by skin prick testing from 26 DM-allergic patients. Airway hyperresponsiveness, serum specific IgE and IL-4 were significantly increased in allergic asthma mouse model sensitized to r-Der f 28. CONCLUSIONS:Der f 28 is a new subtype of allergen in dermatophagoides farinae.