Unique Antigenic Determinants (Idiotypes) Used as Markers in a Patient with Macroglobulinemia and Urticaria

Abstract

An antiserum was raised against a monoclonal IgMk macroglobulin isolated from serum of a patient with recurrent urticaria. The antiserum was made idiotype-specific through adequate absorptions. The anti-idiotype antiserum reacted only with the immunizing protein and its Fab fragments and not with other monoclonal proteins of IgM and IgA class or pooled IgG as assayed in an enzyme-linked immunosorbent assay. IgM antibodies with the same idiotype as the monoclonal IgM protein were detected in the dermal/epidermal junction area of diseased skin. The similar idiotypic determinants could also be demonstrated on membrane-bound molecules of peripheral blood B and T lymphocytes using the immunofluorescence methods.