Emerging concepts of sublingual immunotherapy for allergy

Allergen-specific immunotherapy is the only disease-modifying modality in the treatment of allergy. However, in spite of its validation by abundant experimental data and decades of clinical experience, subcutaneous immunotherapy has not become the mainstay treatment for allergy. The current concepts and methods of immunotherapy are examined with emphasis on the advantageous features of sublingual immunotherapy: cellular and molecular mechanisms are reviewed and the physiology of antigen presentation is discussed; effector cell activation is examined in order to address immunotherapy-precipitated reactions which may reflect on the efficacy of immunotherapy; and stability, dosing and delivery of allergen extracts are reviewed. It can be concluded that allergen-specific sublingual immunotherapy is a useful therapeutic modality which, with proper adjustments, is eligible for wide-scale application as therapy for allergy.