Type II hypersensitivity, also known as cytotoxic hypersensitivity or antibody-mediated hypersensitivity, is a category of immune responses characterized by the inappropriate activation of the immune system against specific target cells or tissues.Examples of type II hypersensitivity reactions include autoimmune hemolytic anemia, Rh incompatibility reactions, and certain drug-induced immune responses.These mechanisms include complement activation, antibody-dependent cell-mediated cytotoxicity (ADCC), and phagocytosis by macrophages.