IgG, kappa light chain (Lane 1), IgG lambda light chain (Lane 2) and IgG Fc fragment (Lane 3) purified from human serum were analysed by Western blotting with Kappa light chains monoclonal antibody, clone MEM-09 (Cat # MAB6445) (Panel A) and IgG (Fc) monoclonal antibody, clone EM-07 (Cat # MAB6465) (Panel B).