Development of Alloantibodies to Non－HLA Systems in Patients on Trans fusion Therapy

Nineteen patients with aplastic anemia or hematological malignancies were prospectively examined with regard to the development of alloantibodies following blood transfusions. Sera obtained at regular intervals were serologically analyzed to detect the lymphocytotoxic antibodies against T cells, B cells and monocytes from a panel of unrelated subjects or their HLA-identical siblings, and the following results were obtained. Anti-HLA-A,B,C, and DR antibodies were detected in 9 out of 19 patients. Among 9 patients who received the preceding transfusions, three had the preformed antibodies. One patient who underwent the preceding pregnancies was already sensitized. Five out of the 15 nonsensitized patients developed transfusion-induced alloantibodies during the period of this study. Three out of the 19 patients demonstrated B cell specific antibodies. The development of anti-HLA-DR antibodies and B cell specific antibodies prior to the occurrence of anti-HLA-A,B and Cantibodies was observed in 3 cases. The development of monocyte specific antibodies was notobserved in this study. The development of these alloantibodies was not dependent on the total volume of blood components transfused. From these results, it is concluded that blood transfusions to the selected candidates for bone morrow transplantation should be reduced to the minimum unless indicated by urgent medical necessity.

alloantibody

Non-HLA antigen

HLA　antigen

Blood transfusion