Atopy -

Atopy typically follows a predictable chronological progression:

: Upon re-exposure, allergens cross-link IgE on the surface of mast cells, causing degranulation and the release of inflammatory mediators like histamine and leukotrienes. 2. The Atopic March caused by skin barrier defects (e.g.

: These cells produce cytokines (IL-4, IL-13) that trigger B cells to differentiate into plasma cells producing allergen-specific IgE. caused by skin barrier defects (e.g.

: Often the first sign in infancy, caused by skin barrier defects (e.g., filaggrin mutations) that allow for epicutaneous allergen sensitization. caused by skin barrier defects (e.g.

: Sensitization through inflamed skin can lead to early-onset food allergies.

The core of atopy is a Type I hypersensitivity reaction driven by a Type 2 immune response.