Question
What are allergens? How do human beings respond to them?
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Answer
Allergens are substances which act as weak antigens and cause inappropriate and excessive immune response. Allergen being a harmless substance initiates antibody formation which in turn binds to the receptors on the mast cell. The mast cell releases chemicals such as histamines, which in turn cause inflammation of the mucous membranes. Many anti-allergic treatments suppress mast cells or neutralise histamines.
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