Pathophysiological Mechanisms Underlying the Efficacy and Safety of Sublingual Immunotherapy

Cristoforo Incorvaia, Luciano Loperfido and Gualtiero Leo

The results of meta-analyses show that sublingual immunotherapy (SLIT) is as efficacious as subcutaneous immunotherapy (SCIT) and more safe in treating patients withallergic rhinitis. In both issues, immunity of the oral mucosa, that is more oriented to tolerance to antigens than respiratory mucosa or skin, plays a pivotal role. In particular, the immunological organs contained in the Waldeyer ring, that is, adenoids, tubal tonsil, palatine tonsil and lingual tonsil are currently investigated concerning their specific function in the response to the allergens administered by SLIT. These studies have the prospective to improve the understanding of immunity of the oral mucosa and to refine the techniques to deliver SLIT.