type II hypersensitivity
Quick Summary
Type II hypersensitivity, also known as cytotoxic reactions, occur when the body's own antibodies destroy cells. This can happen when antibodies bind to antigens on the surface of target cells, triggering mechanisms that lead to cell damage or destruction.1
These reactions can occur when antibodies form against the body's own cells, as seen in autoimmune diseases like autoimmune hemolytic anemia and myasthenia gravis. They can also arise from incompatible blood transfusions, where antibodies attack transfused red blood cells. In some cases, antibodies binding to cell-surface receptors can disrupt normal cellular functions without directly destroying the cell. Unlike Type I reactions, Type II involves circulating immunoglobulins interacting with cell-bound antigens.1
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allergyType II reactions result when antibodies react with antigens that are found on certain “target” cells. The antigens may be natural components of healthy cells, or they may be extrinsic components induced by drugs or infectious microbes. The resultant antigen-antibody complex activates the complement system,…
Read MoreType II reactions result when antibodies react with antigens that are found on certain “target” cells. The antigens may be natural components of healthy cells, or they may be extrinsic components induced by drugs or infectious microbes. The resultant antigen-antibody complex activates the complement system,…
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human diseaseAllergiesIn type II, or cytotoxic, reactions, antibodies are not bound to cells, as in the type I reaction, but circulate freely and interact with cell-bound antigens in the same way that antibodies bind to cells containing infectious agents. Complement is usually activated, leading to cell destruction.…
Read MoreIn type II, or cytotoxic, reactions, antibodies are not bound to cells, as in the type I reaction, but circulate freely and interact with cell-bound antigens in the same way that antibodies bind to cells containing infectious agents. Complement is usually activated, leading to cell destruction.…
Read More