Immunology and Cell Biology

Allergy, Hypersensitivity & Immune Tolerance

This topic explores the mechanisms underlying allergic diseases, hypersensitivity reactions, and immune tolerance. Allergies arise when the immune system mounts inappropriate responses to harmless antigens, driven by IgE production, mast cell activation, and Th2-skewed responses. Hypersensitivity includes rapid reactions, immune complex–mediated inflammation, and delayed-type T-cell responses. Immune tolerance—central and peripheral—is essential for preventing autoimmunity and controlling allergic inflammation. Research focuses on regulatory T cells, tolerogenic dendritic cells, and mechanisms of desensitization. Environmental exposures, genetics, epigenetics, and microbiome imbalances contribute significantly to allergic disease prevalence. Therapeutic innovations include biologics targeting IgE and cytokines, allergen immunotherapy, and strategies to reestablish immune tolerance. Ongoing work aims to prevent sensitization, improve diagnostic tools, and personalize treatment approaches for allergic and hypersensitive conditions.