Recognition of a Non‐HLA‐ABC Antigen Present on B and T Lymphocytes and Monocytes only Detectable with the Indirect Immunofluorescence Test

Abstract

The serum of a 39 yr old male under long-term platelet transfusion therapy for hypoplastic anemia with thrombocytopenia was investigated for the presence of leukocyte and platelet antibodies after the patient had received platelet concentrates from more than 700 random donors. The serological studies of his serum revealed the absence of platelet reactive antibodies, the absence of agglutinating or cytotoxic antibodies against leukocytes, the presence of at least 2 granulocyte-specific antibodies, 1 with the specificity anti-NA2 and the other with an undefined specificity, both only detectable by indirect immunofluoresence, and the presence of cytotoxic-negative fluorescence-positive peripheral-blood-mononuclear-cell-reactive antibodies, not directed against HLA-A, B or C antigens. The significance and implications of these findings were briefly discussed.