[Cross-reactivity of HLA antigens of the donor and patient--a cause of unsuccessful thrombocyte transfusion in patients with HLA antibodies].

In the microlymphocytotoxic test, specific HLA sera reacted positively with 74.74% of 99 examined samples of lymphocytes which failed to have corresponding HLA antigens yet contained HLA antigens cross-reacting with the given HLA antibody. In the serum of some patients HLA antibodies were established against HLA antigens cross-reacting with the antigens of the patient. The results show that it is not suitable to select thrombocyte and leukocyte donors on the basis of cross-reacting antigens. Therapy of patients with HLA antibodies may be clinically unsuccessful and even result in posttransfusion reaction. Patients who do not have HLA antibodies may develop them.