Allergen immunotherapy: definition, indications, and reactions

Area of Science:

• Immunology
• Allergology
• Clinical Medicine

Background:

• Allergen immunotherapy (AIT) is a disease-modifying treatment for type I hypersensitivity reactions.
• It is indicated for allergic rhinitis, conjunctivitis, asthma, and Hymenoptera hypersensitivity.
• Specific IgE antibodies must be documented for AIT eligibility.

Purpose of the Study:

• To review the indications, mechanisms, and administration of specific allergen immunotherapy.
• To highlight the potential of AIT in preventing new allergic sensitizations and asthma development.
• To discuss the immunological changes associated with AIT.

Main Methods:

• Review of existing studies on allergen immunotherapy.
• Analysis of immunological mechanisms including T-cell regulation, antibody production, and mediator release.
• Description of subcutaneous and sublingual administration routes.

Main Results:

• AIT indications include inadequate symptom control, desire to reduce morbidity/anaphylaxis risk, adverse drug effects, and unavoidable allergen exposure.
• Immunotherapy may prevent new allergic sensitizations and asthma.
• Key immunological changes involve regulatory T/B cells, IL-10, TGF-β, suppressed Th2 proliferation, increased IgG4, and reduced mediator release.

Conclusions:

• Allergen immunotherapy is a valuable therapeutic option for specific allergic conditions.
• It induces significant immunological changes leading to tolerance.
• Further research is needed for its application in food allergies.