Next-Generation Allergen-Specific Immunotherapy for Japanese Cedar Pollinosis Using Molecular Approaches

Japanese cedar (JC) pollinosis is the most major IgE-mediated type I allergic disease in Japan. Allergen-specific immunotherapy is the only curative treatment for allergic diseases. Subcutaneous immunotherapy and sublingual immunotherapy have been introduced in Japan for JC pollinosis, but do not avoid some adverse side effects, because the natural allergens used as tolerogens cross-link with specific IgE types on mast cells and basophils. To make immunotherapy for JC pollinosis safer, more effective and convenient, rice-based oral allergy vaccines using hybrid peptides composed of multiple T-cell epitopes or recombinant deconstructed hypoallergenic derivatives derived from major allergens — Cry j 1 and Cry j 2 — have been developed and their efficacy and safety evaluated by oral administration of transgenic rice seeds. Furthermore, recombinant modified JC allergens conjugated with various immunomodulatory molecules and DNA-based vaccines have been created and their efficacy assessed.