Type IV hypersensitivity reactions are caused by

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Quizplus · Accepted Answer

Type IV hypersensitivity reactions are also known as delayed-type hypersensitivity and are characterized by T cell-mediated immune responses against antigens. This type of hypersensitivity does not involve antibodies, unlike the other types. Instead, the response is initiated by antigen-specific T cells, usually of the CD4+ helper T cell subtype. These T cells migrate to the site of antigen exposure and activate macrophages and other immune cells, leading to tissue damage and inflammation. Examples of type IV hypersensitivity include contact dermatitis, tuberculin reactions, and allergic reactions to metals, dyes, and drugs.

Type IV Hypersensitivity Reactions Are Caused by