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Allergy and Hypersensitivity

K. J. Goodrum2006

Types of Immune Hypersensitivity Reactions

Types of Immune Hypersensitivity Reactions

Properties of Inhaled Allergens

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Penetration of epithelial Barriers by Allergens

Early IL-4 response promotes Th2 development that drives B cell class switching to IgE

Signaling through Stat6 is necessary for Th2 responses.

Th2 cells support IgEresponses.

Antigen binding to IgE on mast cells leads to amplification of IgE production

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Mast cell activation affects many tissues

Molecules released upon activation of mast cells

Molecules released upon activation of mast cellsToxic granule proteins and inflammatory substances

released upon activation of eosinophils

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Toxic granule proteins and inflammatory substances released upon activation of eosinophils Acute vs.

late phase inflammatory responses

TH2 mediated chronic inflammation in Asthma

Treatment approaches for IgE-mediated Allergy

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Type II Cytotoxicreaction Immune Complex mediated local inflammation such as

in Arthus Reaction

Serum Sickness: an Immune complex disease

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Type IV Hypersensitivity Reactions Stages of a Type IV Hypersensitivity Reaction

Th1 derived cytokines and chemokinesdirect Type IV reactions

Allergic Contact Dermatitis: A type IV reaction

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Blistering skin lesions on hand of patient with poison ivy contact dermatitis (a type IV reaction)

Granulomatous inflammation is a consequence of chronic Type IV reactions