Competitive inhibition ELISAs confirm polyreactive binding patterns of murine MALT lymphoma antibodies. (A-C) A single concentration of the indicated recombinant murine antibodies 3, 11, and 10 (10 μg/mL) was incubated with plate-coated (solid-phase) antigen in the presence of a 10× excess of the same antigen in soluble form or increasing concentrations of an alternative soluble antigen. Three representative inhibition assays are shown and demonstrate the ability of different soluble-phase antigens to inhibit the binding of the antibody to solid-phase antigens. In contrast, BSA did not block binding of Abs 3 and 11 even at 100× excess concentrations (A-B right panels). Error bars represent SEM.