Which condition is an example of Type II hypersensitivity?

Type II hypersensitivity reactions, also known as cytotoxic hypersensitivity, involve the immune system producing antibodies against specific antigens that are present on cell surfaces. These reactions often result in the destruction of the target cells, either through complement activation or phagocytic cell engagement.

Graves' disease is an autoimmune disorder that serves as a prime example of Type II hypersensitivity. In this condition, antibodies are produced against the thyroid-stimulating hormone receptor (TSHR) on thyroid follicular cells. These antibodies stimulate the overproduction of thyroid hormones, leading to hyperthyroidism. The action of these antibodies directly alters the function of the thyroid cells, showcasing the characteristic mechanism of Type II hypersensitivity.

In contrast, the other conditions listed are examples of different types of hypersensitivity. Asthma typically involves Type I hypersensitivity mechanisms due to IgE-mediated responses to allergens. Contact dermatitis is an example of Type IV hypersensitivity, which is mediated by T-cell responses and does not involve antibodies. Systemic lupus erythematosus (SLE) involves a complex autoimmune process with traits of both Type II and Type III hypersensitivity, but it is primarily recognized as a Type III hypersensitivity disorder due to the formation of immune complexes.

Thus, Graves