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Hypersensitivity

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Hypersensitivity types in 4 minutes

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Immediate response: Type I Hypersensitivity Reaction

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Type I hypersensitivity reaction in 2 mins!

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Immune Complex-Mediated Hypersensitivity: Type III Hypersensitivity Reaction

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Type 2 hypersensitivity reaction in 2 mins!

Hypersensitivity refers to undesirable reactions produced by the normal immune system, including allergies and autoimmunity. They are usually referred to as an over-reaction of the immune system and these reactions may be damaging, uncomfortable, or occasionally fatal. Hypersensitivity reactions require a pre-sensitized (immune) state of the host. They are classified in four groups after the proposal of P. G. H. Gell and Robin Coombs in 1963.
  • Coombs and Gell classification