**2.2 Immunopathogenesis of AD with food allergy**

The immunologic phases of food allergy in AD include a sensitization phase and an effector phase (Fig. 1) [2]. During the sensitization phase, the tolerance of a subject to a specific allergen is determined. Response to that allergen, either allergic or tolerant, occurs in the effector phase.

Fig. 1. Scheme of immunopathogenesis of food allergy in atopic dermatitis. When allergen is challenged, the immune system check the memory. In the neosensitization, immunologic memory of allergy is induced in the Th2 polarized status, or tolerized in normal status. In the immunologic process, IgE-mediated allergy or non-IgE-mediated allergy is formed when food allergen is to be memorized to react as allergic reactions. If food allergen is rechallenged, atopic dermatitis is appeared by non-IgE-mediated food allergy or IgE-mediated allergy including urticaria to anaphylactic shock occured. If allergen is memorized being tolerant, there is no reaction even by any further challenge by allergen. IgE-mediated food allergy and non-IgE-mediated allergy is apparently different in the immunopathogenesis as well as clinical manifestations.

relevant treatment techniques, including tolerance induction for food allergy (TIFA), have been markedly advanced and well-established [7]. In this chapter, updates on the diagnosis

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disease [1] that is characterized by non-IgE-mediated allergic skin inflammation, in which allergen-specific Th2 cells play a major role in the pathogenesis of the inflammation [2]. The appearance of atopic dermatitis is characterized by late eczematous reactions, which result from an

The immunologic phases of food allergy in AD include a sensitization phase and an effector phase (Fig. 1) [2]. During the sensitization phase, the tolerance of a subject to a specific allergen is determined. Response to that allergen, either allergic or tolerant, occurs in the

Fig. 1. Scheme of immunopathogenesis of food allergy in atopic dermatitis. When allergen is challenged, the immune system check the memory. In the neosensitization, immunologic memory of allergy is induced in the Th2 polarized status, or tolerized in normal status. In the immunologic process, IgE-mediated allergy or non-IgE-mediated allergy is formed when food allergen is to be memorized to react as allergic reactions. If food allergen is rechallenged, atopic dermatitis is appeared by non-IgE-mediated food allergy or IgE-mediated allergy including urticaria to anaphylactic shock occured. If allergen is memorized being tolerant, there is no reaction even by any further challenge by allergen. IgE-mediated food allergy and non-IgE-mediated allergy is apparently different in the immunopathogenesis as

and relevant treatments for food allergy in AD are described

**2. Atopic dermatitis** 

allergen-specific Th2 immune response.

**2.2 Immunopathogenesis of AD with food allergy** 

**2.1 Definition** 

effector phase.

well as clinical manifestations.

Humans are continually challenged by foreign particles, including pathogens and foods. Protection from these foreign substances is mediated by effective immune responses (effectors). Protection from immune responses directed against food occurs by an immune tolerance response (tolerance). Allergy is one type of effector immune response that is the consequence of allergic sensitization. Allergic sensitization occurs from a Th1/Th2 imbalance [9]. There are 2 classes of allergic effector mechanisms: IgE-mediated and non-IgE-mediated allergic reactions. An IgE-mediated allergic response occurs if allergenspecific IgE is activated after exposure to the specific allergen. IgE-mediated immune reactions include urticaria, asthma, and rhinitis.

IgE has been positioned at the center of focus in allergy and allergic disease research. However, a major characteristic of AD is its non-IgE-mediated response.
