Definition: HLA Antibody and PRA Screening

Explanation: A test procedure which will reveal if the patient has antibody to other Human Leukocyte Antigens (HLA) PRA (Percent Reactive Antibody) is the amount of HLA antibody in a patient’s serum. If, for example, the patient’s serum reacts with 30 out of 60 HLA, then the patient’s PRA is 50%. The PRA is calculated for each monthly serum sample. In addition to determining how much or how little PRA a patient has, we need to know how specific the antibody is. Some patients have one or two antibody specificities, while others have numerous specificities. Since HLA antibody can "come and go," it is important to test