Answer: C - A Type IV hypersensitivity reaction involves binding a class II MHC to a TCR. It also consists of the presentation of antigens by macrophages to T cells, thus producing tissue destruction.
Type IV hypersensitivity reaction is a cell-mediated reaction that can respond to contact with specific allergens, resulting in contact dermatitis, or in response to some diagnostic procedures, such as in the tuberculin skin test. Certain trigger allergens must be avoided to treat the condition.
Type IV hypersensitivity reactions, also known as delayed-type hypersensitivity reactions, are immune responses that occur several hours or days after exposure to an allergen or irritant. These reactions are mediated by T cells, a type of immune cell, and typically involve inflammation and tissue damage.
In a Type IV hypersensitivity reaction, the immune system recognizes an allergen or irritant as foreign and mounts an immune response against it. This response involves the activation and recruitment of immune cells, such as T cells and macrophages, to the site of the allergen or irritant. These immune cells release various substances, such as cytokines and chemokines, that can cause inflammation and tissue damage.
Type IV hypersensitivity reactions can affect many different organs and tissues in the body. The symptoms and signs of these reactions can vary widely depending on the site of the response and the underlying cause. Some common symptoms of a Type IV hypersensitivity reaction include redness, swelling, itching, and warmth at the site of the response. These reactions can lead to organ damage or even organ failure in more severe cases.
