alloimmunisatsioon

Alloimmunisation, also known as allosensitisation or alloimmunization, is a type of immune response that occurs when an individual's immune system recognises and responds to foreign antigens, specifically those from another individual of the same species. This phenomenon is most commonly observed in the context of blood transfusions, organ transplants, and pregnancy.

In blood transfusions, alloimmunisation can lead to the formation of antibodies against the foreign blood cells, which can cause a hemolytic transfusion reaction. This reaction occurs when the antibodies attack and destroy the transfused red blood cells, leading to a decrease in the recipient's hemoglobin levels and potential anemia.

In organ transplants, alloimmunisation can result in the rejection of the transplanted organ. The recipient's immune system recognises the foreign organ as non-self and mounts an immune response to eliminate it. This can lead to the destruction of the transplanted organ and the need for immunosuppressive therapy to prevent rejection.

During pregnancy, alloimmunisation can occur when the mother's immune system recognises fetal antigens as foreign. This can lead to the formation of antibodies against the fetus, which can cause hemolytic disease of the newborn if the mother is Rh-negative and the fetus is Rh-positive.

Alloimmunisation is a complex process involving the interaction of various immune cells, such as T cells and B cells, and the production of antibodies. The severity and outcome of alloimmunisation can vary depending on several factors, including the strength of the immune response, the type of antigen, and the individual's overall health status.