The responses observed in type IV hypersensitivities result from the action of
A) IgE antibodies and mast cells.
B) T cells and phagocytes.
C) IgG and complement.
D) autoantibodies.
E) inflammatory chemicals.

Question

Quizplus · Accepted Answer

Type IV hypersensitivity is also known as delayed-type hypersensitivity, and it involves the activation of T cells and macrophages (a type of phagocyte). This response can take 24-72 hours to develop and manifests as skin reactions, granuloma formation or tissue damage. This mechanism is responsible for the allergies to poison ivy and tuberculosis.

The Responses Observed in Type IV Hypersensitivities Result from the Action