Mechanisms of Tolerance Induction
Food allergy is defined as an immune-mediated adverse reaction to specific foods. This problem is becoming more widespread and affects up to 8% of children and 5% of adults in Western countries. Currently, there are no effective strategies to induce permanent tolerance: management of food allergies consists of recognizing the adverse reactions and treating the symptoms. Food allergy arises when oral tolerance fails to develop in early life or is breached at an older age.
The initial exposure to food allergens occurs predominantly via the gastrointestinal tract or the skin, and can occur at different pre-and postnatal stages. Exposure to food allergens such as peanut and hen’s egg via an inflamed and disrupted epithelial barrier in the absence of oral feeding is an important pathway of allergic IgE sensitization in infants with severe atopic dermatitis. An additional route of allergic sensitization to food could be via the airway tissue.