A monoclonal antibody may show cross-reactivities in Ouchterlony assays but not in other assays.
A monoclonal antibody to human IgG was tested with myeloma proteins of the four IgG subclasses. When tested by immunofluorometric assay, enzyme-linked immunosorbent assay, hemagglutination and hemagglutination inhibition assays, the antibody reacted with IgG3 but not with the other three IgG subclasses. When tested by Ouchterlony assays in the presence of polyethylene glycol, the antibody formed lines with all four IgG proteins. The line with IgG3 was sharp and stable, but the lines with the other three IgG subclasses tended to blur with time and with the lower PEG concentrations. These findings show that Ouchterlony assays can reveal cross-reactions of a monoclonal antibody that can be missed by more sensitive assays.
D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D006385:Hemagglutination Inhibition Tests; D006386:Hemagglutination Tests; D006801:Humans; D005779:Immunodiffusion; D007074:Immunoglobulin G / Q000145:classification / Q000276:immunology*; D009194:Myeloma Proteins / Q000276:immunology
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D009194:Myeloma Proteins; C048844:anti-IgG