HLA AND TRANSFUSION

Using published data, the role of the HLA system for transfusion of ce llular blood components is described. Transfusion-associated immunomod ulation and the causative role of HLA in other side effects of transfu sion therapy are discussed, using review articles and original papers from the German and English literature as sources. The HLA system has important implications for transfusion therapy. Sensibilization of rec ipients with consecutive formation of HLA antibodies impaires the supp ort of thrombocytopenic patients and may cause febrile transfusion rea ctions. HLA antibody formation in donors may result in transfusion-ind uced acute lung injury. The transfusion of viable lymphocytes may caus e graft-versus-host disease in immunocompromised recipients or after d irected donations from relatives, in rare cases even without these con ditions. The clinical implications of transfusion-associated immunomod ulation are judged differently. In conclusion, the HLA system is invol ved in major transfusion-related effects. Stringent verification of th e transfusion indication, the application of leucocyte-poor products a nd the irradiation of blood components for selected groups of recipien ts are important strategies of modern transfusion therapy.