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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Allergic hypersensitivity is mediated by -
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The correct answer is  Atopy or allergic hypersensitivity is type I which is mediated by IgE. Atopic sensitivity is due to overproduction of IgE antibodies. In normal individuals , the inhalent and ingested antigens are delt with IgA lining the respiratory and intestinal mucosa and thus do not come in contact with IgE producing cells. When IgA is deficient, antigen cause massive stimulation of IgE forming cells leading to overproduction of IgE. Reference : Anathanarayan & paniker's 9th edition, pg no:165 <\p>