{"id":4888,"date":"2019-05-17T17:12:04","date_gmt":"2019-05-17T17:12:04","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-dutchess-ap1\/chapter\/part-vi-blood-typing\/"},"modified":"2019-09-25T09:23:53","modified_gmt":"2019-09-25T09:23:53","slug":"blood-typing-and-blood-transfusion","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-dutchess-ap1\/chapter\/blood-typing-and-blood-transfusion\/","title":{"raw":"Blood Typing and Blood Transfusion","rendered":"Blood Typing and Blood Transfusion"},"content":{"raw":"
\r\n
\r\n
\r\n
\r\n

Blood transfusions in humans were risky procedures until the discovery of the major human blood groups by Karl Landsteiner, an Austrian biologist and physician, in 1900. Until that point, physicians did not understand that death sometimes followed blood transfusions, when the type of donor blood infused into the patient was incompatible with the patient\u2019s own blood. Blood groups are determined by the presence or absence of specific marker molecules on the plasma membranes of erythrocytes. With their discovery, it became possible for the first time to match patient-donor blood types and prevent transfusion reactions and deaths.<\/p>\r\n\r\n

\r\n

Antigens, Antibodies, and Transfusion Reactions<\/h2>\r\n

Antigens are substances that the body does not recognize as belonging to the \u201cself\u201d and that therefore trigger a defensive response from the leukocytes of the immune system. (Seek more content for additional information on immunity.) Here, we will focus on the role of immunity in blood transfusion reactions. With RBCs in particular, you may see the antigens referred to as isoantigens or agglutinogens (surface antigens) and the antibodies referred to as isoantibodies or agglutinins. In this chapter, we will use the more common terms antigens and antibodies.<\/strong><\/p>\r\n

Antigens<\/strong> are generally large proteins, but may include other classes of organic molecules, including carbohydrates, lipids, and nucleic acids seen on RBCs. Following an infusion of incompatible blood, erythrocytes with foreign antigens appear in the bloodstream and trigger an immune response. Proteins called antibodies (immunoglobulins), which are produced by certain B lymphocytes called plasma cells, attach to the antigens on the plasma membranes of the infused erythrocytes and cause them to adhere to one another.<\/p>\r\n\r\n