[Mechanisms of allergen-specific immunotherapy]

Area of Science:

• Immunology
• Allergology
• Pharmacology

Background:

• Allergen-specific immunotherapy (AIT) is a key treatment for allergic diseases.
• Subcutaneous immunotherapy (SCIT) was historically dominant, but sublingual immunotherapy (SLIT) is gaining global traction due to a better safety profile.
• Standardized SLIT preparations approved in Japan in 2014 have accelerated its adoption.

Purpose of the Study:

• To review the mechanisms of allergic inflammation and AIT.
• To discuss the current understanding and challenges in AIT.
• To highlight future directions for improving AIT efficacy.

Main Methods:

• Review of existing literature on AIT mechanisms, including sensitization and elicitation phases of allergic inflammation.
• Analysis of proposed AIT mechanisms: desensitization and immune tolerance.
• Exploration of challenges and emerging research in AIT, including biomarkers and genetic influences.

Main Results:

• Allergic inflammation involves sensitization (IgE production) and elicitation (mast cell degranulation, Th2 activation).
• AIT mechanisms include desensitization (reduced mast cell/basophil responsiveness) and immune tolerance (IgG4 production, Treg induction, IL-10 secretion).
• Challenges remain, notably the lack of predictive biomarkers for AIT efficacy.

Conclusions:

• SLIT is increasingly adopted globally for allergy treatment.
• Understanding AIT mechanisms is crucial for optimizing treatment.
• Advances in genetic and single-cell analysis hold promise for identifying biomarkers and improving AIT outcomes.