Characteristics of the epitope of leukotriene B4 recognized by a highly specific mouse monoclonal antibody

Mouse monoclonal IgG2b antibodies to leukotriene B4 bind 3H]leukotriene B4 with an affinity one-thirtieth to one-third that of different rabbit antibodies to leukotriene B4. The concentrations of related ligands required to inhibit by 50% the binding of 3H]leukotriene B4 define cross-reactivities of approximately 100% for carboxyl-derivatives of leukotriene B4, 10% for 12(S)-leukotriene B4 and 8 cis-leukotriene B4, which were not distinguished from leukotriene B4 by polyclonal antibodies, 3-5% for the two isomers of 6 trans-leukotriene B4, 5% for 20-OH-leukotriene B4 and 20-COOH-leukotriene B4, and less than 1% for other leukotrienes, mono-hydroxy-eicosatetraenoic acids, and the two leukotriene B4-like isomers of 8, 15-di-hydroxy-eicosatetraenoic acid. Thus the monoclonal combining site is highly specific for the di-hydroxy-triene portion of leukotriene B4.