Plant-based vaccines against pollen allergy

Abstract

Allergen-specific immunotherapy (SIT) is the only clinically available treatment that targets the cause of allergic disease and leads to long-lasting relief from allergic symptoms. Conventional treatment involves repeated subcutaneous injections with increasing doses of a crude allergen extract for at least 3 years, sometimes accompanied by adverse side effects, such as anaphylaxis. To create convenient, safe, and effective allergen-SIT, an exchange from injections with natural allergens to oral administration with hypoallergenic derivatives has been examined. Since tolerogens bioencapsulated within plant cells can be effectively delivered to immune cells in gut-associated lymphoid tissues (GALT) without severe degradation, plant-based allergy vaccines containing hypoallergenic tolerogens against tree pollen allergens permit the high-dose administration of treatments without side effects, which has given rise to high-efficacy innovative immunotherapy. Oral seed-based immunization as a vaccination strategy has many advantages for the induction of immune tolerance because of its high production ability and stability at ambient temperatures in addition to its simplicity, low cost of production, and safety associated with plant systems. Seed-based pollen allergy vaccines have been exploited and their efficacy has been confirmed using oral administration model mice.