AUTOANTIBODIES TO CD45 IN SYSTEMIC LUPUS-ERYTHEMATOSUS

Western blotting with U937 cell extracts as the substrate, and enzyme- linked immunosorbent assays (ELISA) with U937-, Jurkat- and Daudi cell -purified CD45 molecules were used to detect anti-CD45 reactivity in p atients with systemic lupus erythematosus (SLE). By immunoblotting, 16 of 64 SLE sera were shown to be positive (25.0%). In the ELISAs, 13 o ut of 18 SLE sera reacted with the target CD45. Of these, three were n ot detectable on the blot. Importantly, 12 of these ELISA-positive ser a contained IgM and IgG autoantibodies. Neuraminidase-treatment of U93 7-precipitated CD45 molecules enhanced the reactivity to most of the i soforms, indicating that the antibodies may bind to asialylated polysa ccharides. (C) 1998 Academic Press