Type II Hypersensitivity (Cytotoxic Hypersensitivity)

Type II hypersensitivity, also known as cytotoxic hypersensitivity, occurs when the immune system mistakenly attacks the body's own cells. This happens when antibodies, which are normally meant to fight infections, bind to healthy cells and mark them for destruction. This can lead to conditions like autoimmune hemolytic anemia, where red blood cells are destroyed, or transfusion reactions, where the body reacts against incompatible blood types. The result is tissue damage and dysfunction, as the immune system confuses the body’s own healthy cells for foreign invaders.