7. Future perspectives
The important role of IgE in type 1 allergic diseases has been known for a very long time. The functional role of allergen-specific IgG and IgA antibodies induced by AIT has shown their ability to interfere with the interaction of IgE with the allergen. In addition, transplacental or breastfeeding-mediated transfer of immune complexes of maternal IgG with allergens to the fetus may protect against sensitization to allergens in early life.
The knowledge we have gained over the last two decades has been instrumental in developing novel therapeutic approaches by targeting IgE itself with anti-IgE antibodies or receptor-targeting antibodies, enhancing blocking antibodies by AIT or even passive transfer of allergen-specific IgG to allergic patients (see Box 1 for methods used to measure these allergen-specific antibodies and their function in more detail). This knowledge may help to further establish the relevance of blocking antibodies as a biomarker for clinical effects of AIT.
Finally, this may lead to future therapeutic approaches such as combination treatments with therapeutic antibodies and AIT or OIT (e.g. combination with anti-IgE, allergen-specific IgG, or cytokine-directed antibody therapies), as well as preventive approaches such as maternal allergen vaccination to enhance delivery of allergen-specific IgG and IgA antibodies during pregnancy and early life to prevent sensitization to respiratory and food allergens.