ANTIPLATETLET ANTIBODIES AGAINST GPIIB IIIA IN SYSTEMIC-SCLEROSIS/

An enzyme-linked immunosorbent assay and western immunoblotting analys is were used to detect anti-platelet antibodies in the sera of 50 pati ents with systemic sclerosis. Eleven (22%) positive sera were found by ELISA. Serial investigations showed that the presence of these antibo dies was often transient. Immunoblotting analysis demonstrated that th e antibodies were directed against a 114 kDa antigen. Using monoclonal antibody, anti-platelet antibodies directed against gpIIIa were found in 4 cases. Similar to immune thrombocytopenia and lupus erythematosu s, a significant portion of the anti-platelet antibodies were also dir ected against the glycoprotein complex IIb/IIIa in systemic sclerosis.