alloantibody
Noun An antibody that is produced by an individual in response to, and reactive against, antigens from another individual of the same species. These antibodies are "naturally occurring" in the sense that they are generated following exposure to foreign tissues or cells (like from a blood transfusion, tissue graft, or pregnancy) rather than being experimentally induced.
The term is used primarily in immunology, transfusion medicine, and transplantation biology to describe antibodies that target alloantigens (non-self antigens from the same species). It is a technical term.
Examples * The patient developed an alloantibody after receiving a blood transfusion. * Screening for alloantibodies is a critical step before organ transplantation. * The presence of maternal alloantibodies can affect a fetus in conditions like hemolytic disease of the newborn.
- Alloantibody vs. Autoantibody: An reacts against antigens from a genetically different member of the same species. This contrasts with an , which reacts against the body's own tissues.
- Clinical Significance: The detection and identification of specific alloantibodies are crucial for ensuring compatibility in blood transfusions (to prevent hemolytic reactions) and in solid organ or hematopoietic stem cell transplants (to prevent rejection).
- Alloantigen (noun): The foreign antigen from a member of the same species that stimulates the production of an alloantibody.
- Isoantibody (noun): A synonym for alloantibody, though "alloantibody" is more commonly used in modern scientific literature.
- Alloimmunization (noun): The process of developing an immune response, including the production of alloantibodies, following exposure to alloantigens.
- Isoantibody
The core meaning is specific and technical. It does not refer to antibodies against pathogens (like viruses or bacteria from any species) or to experimentally manufactured monoclonal antibodies. Its use is confined to the context of immunological differences within a species.
- an antibody that occurs naturally against foreign tissues from a person of the same species