Antibodies Against Platelet Glycosphingolipids: Detection in Serum by Quantitative HPTLC-Autoradiography and Association With Autoimmune and Alloimmune Processes

In order to assess the importance of glycosphingolipids (GSL) in the immunology of the platelet, serum antibody binding to immobilized, purified platelet GSLs have been quantitatively measured via high-performance thin-layer chromatography (HPTLC), 125l-radio-immunolabeling, autoradiography, and densitometry. Thirteen neutral GSL bands were detected at Rf .03 through .64 (CHCI3-CH3OH- H2O, 65:25:4) after extraction and chromatography (DEAE- Sephadex and Bio-sil A). Both IgM and IgG serum antibody binding was determined for 50 subjects from four groups: normal blood donors (NBD, n = 18); leukemia patients with nonimmune thrombocytopenia (NIT, n = 10); patients with systemic lupus erythematosus (SLE, n = 10); and patients with chronic autoimmune thrombocytopenia (CATP, n = 12). The ABO typing of these 50 subjects also allowed correlation of serum antibody binding with A blood group antigen expression. These studies reveal: (1) anti-GSL binding at band .06 is associated with blood group A alloantigen expression for both IgG and IgM (P