Efficacy evaluation of Der p 1 DNA vaccine for allergic asthma in an experimental mouse model.

Der p 1 is a major allergen that reacts with IgE in more than 70% allergic sera, hence a good candidate for DNA vaccine development. Previous study demonstrated that intramuscular injection of plasmid DNA containing wild type Der p 1 gene induced specific Th1 skewed immune response. The aim of this study is to further optimize the DNA construct to achieve preventive and therapeutic efficacies. An optimized construct, containing mouse Igkappa light chain leader sequence followed by codon optimized mature Der p 1 gene, was generated and used to prevent or treat Der p1 induced allergic asthma in an experimental model. Results showed that this optimized construct was effective in the inhibition of Der p 1 specific IgE levels, attenuation of Th2 response and reduction of airway hyperresponsiveness in terms of prophylactic efficacy. It also showed therapeutic efficacy in IgE inhibition and up-regulation of IgG2a and IFN-gamma. The information obtained here could facilitate the design of DNA vaccines for allergy in general.