Monoclonal antibodies against HOCl-induced epitopes, have been produced. These monoclonal antibodies were mainly raised against oxLDL. One of these monoclonal antibodies was able to bind to the HOClinduced epitopes on HSA and based on this antibody (clone 2D10G9) HOCl-modified proteins can be detected in human tissue [13] [14] [15] 29] . It was suggested that the epitope recognized by this monoclonal antibody is of a complex conformational type, but almost nothing is known about the nature of the 2D10G9 epitope. The fact that antibodies can be induced by immunization and HOCl-induced epitopes can easily be detected in human tissue [32] indicates that these HOCl-induced protein structures are chemically and structurally related and seem to be very stable.