Clinical importance of the rare erythrocyte antibody anti-Jra.

Alloantibodies to high-frequency antigens create serious problems for a transfusion service. It is obviously important to know the clinical significance of such antibodies. In the present study, an attempt was made to determine this with respect to the antibody anti-Jra in a patient of the rare blood type Jr(a-). A small volume of 51Cr-labeled Jr(a+) erythrocytes was infused intravenously and cell survival was monitored. The T1/2 of these cells was approximately 80 minutes indicating the in vivo potency of the antibody.