A polyspecific monoclonal anti-DNA autoantibody also binds to cell-surface protein(s)

A monoclonal anti-DNA autoantibody (EM85) produced in an autoimmune MRL/lpr/lpr mouse was studied. Its antigenic specificity was demonstrated to be directed against single-stranded DNA, double-stranded DNA, and also a variety of polynucleotides. We have recently reported that a murine monoclonal anti-DNA autoantibody produced in autoimmune B/W mice, with specificity for double-stranded DNA, also binds to cell-surface protein(s). We show here that EM85, which recognizes a variety of polynucleotides, also binds to protein(s) on the surface of Raji cells. These data indicate that the antigenic determinant, recognized by this monoclonal anti-DNA antibody, is common to a variety of polynucleotides and cell-surface protein(s).