Isoantigens found on red blood cells (RBCs) may lead to a hemolytic transfusion reaction because:

Question

Quizplus · Accepted Answer

Isoantigens (ABO antigens) on RBCs could be the cause of a hemolytic transfusion reaction if a patient were to be given blood of a different type. This can occur because individuals contain antibodies to the antigens that they do not possess. If a person was given donor blood of a type that possessed antigens that the patient did not have, then a rapid antibody-mediated hemolysis would occur. For example, if a patient has type A blood, then the patient has A antigens on the RBC surface, and anti-B antibodies circulating in the serum. If that patient were to be given type B or type AB RBCs, then the anti-B antibodies would hemolyze the donor cells. The patient could have received type A blood as a match, or type O blood because type O does not have A or B antigens on the cell surface, so no reaction would occur. This antibody-mediated reaction occurs through pre-existing antibodies, so T and B cell activation are not involved, and this is not an allergic response.

Isoantigens Found on Red Blood Cells (RBCs) May Lead to a Hemolytic