A monoclonal anti-DNA antibody also binds to cell-surface protein(s).

A murine monoclonal anti-DNA antibody ( PME77 ) has been found to bind tightly to the plasma membrane of Raji cells. We show here that this monoclonal anti-DNA antibody reacts in a radioimmunoassay with the cell surface of a variety of mammalian cell types and that the antigenic determinant recognized by the monoclonal anti-DNA antibody at the surface of Raji cells is resistant to DNase. It belongs to polypeptides removed from the cell surface by a mild proteinase K treatment.