Derp2-mutant gene vaccine inhibits airway inflammation and up-regulates Toll-like receptor 9 in an allergic asthmatic mouse model.

Background: A DNA vaccine encoding the whole segment of the Derp2 allergen could prevent allergic airway inflammation in a Derp2 allergen-induced allergic airway inflammation mouse model. Objective: This study investigated the effect of DNA vaccine encoding Derp2-mutant gene in which an IgE epitope was deleted on airway inflammation and the role of TLR9 in the asthmatic mouse model. Methods: A Derp2-mutant DNA vaccine was constructed. Mice were immunized, sensitized and challenged. Airway inflammation, airway hyper reactivity (AHR) and serum antibody were tested. The expression of Toll like receptor9 (TLR9) was detected with western-blot and immune-histochemistry. Results: We demonstrated that the Derp2-mutantDNA induced IgG2a and inhibited IgE production, inhibited airway allergenic inflammation and AHR. Derp2-mutant-DNA vaccine induce TLR9 expression in lung tissue. Conclusions: The data indicate that allergen DNA vaccine deleted IgE epitope could prevent allergenic airway inflammation, AHR, and up-regulate lung TLR9 express. (Asian Pac J Allergy Immunol 2010;28:287-93)