What is the difference between a trigger and an allergen?
Prof. S. Živanović
All allergens are triggers, but not all triggers are allergens!
A trigger is a substance capable of causing an asthma exacerbation. Examples of triggers are: - cold air - physical effort - viral infections of the upper respiratory tract - hyperventilation - air pollutants - professional agents - allergens: dust mites, mold, pollen, animal hair
An allergen is a specific form or type of trigger that induces allergic asthma. Examples of allergens are pollen, house dust mites, cat saliva, etc. These are protein substances that enter the body through the skin or mucous membrane of the respiratory or digestive tract and cause sensitization and symptoms.
An allergic reaction or allergy is an inadequate and harmful immune response to normally harmless substances. Today, allergy is considered immune hypersensitivity that can lead to a whole spectrum of diseases with different pathological mechanisms and different approaches in diagnosis, therapy and prevention.
A protein capable of triggering the immune system to start producing IgE antibodies is called a primary sensitizer. The process of allergic sensitization itself is multifactorial and is influenced by numerous biological and molecular characteristics of proteins (allergens) as well as interaction with different pathways of the immune system.
Sensitization is a complex interaction between the exposed person (inherited risk of becoming allergic) and the time of exposure (at the earliest age of life the immune system is more susceptible to sensitization, but also to the induction of tolerance), the dose of the allergen (high exposure at an early age can lead to a deviation in the direction of tolerance ), exposure context (environmental exposure such as pollution, microbes, parasites, diet, lifestyle) and endogenous protein properties.
Literature
Van Ree R. Allergens-structure and function. In : Global Atlas of Allergy, eds.EACI; 2014:6-8.
