The peroxidase-anti-peroxidase (PAP) approach utilizes a complex of enzyme and antibody to facilitate amplification of signal, indirectly detecting the amount of primary antibody used in an assay. Generated in Mouse, the PAP complex can be utilized in any assay that utilizes a mouse primary antibody. With the addition of a secondary antibody that recognizes mouse, the reporter PAP complex allows for amplification of the luminescent signal (as three molecules of enzyme are bound to every two immunoglobulins).