DEVELOPMENT OF MONOCLONAL-ANTIBODIES TO GIZZEROSINE, A TOXIC COMPONENT PRESENT IN FISH-MEAL

This study is the first report of the development of monoclonal antibo dies (MAbs) against gizzerosine (GZ), one of the causative agents of b lack vomit, a serious poultry disease. Balb/c mice were immunized with different GZ conjugates; the most immunogenic conjugate in experiment al animals was determined by enzyme-linked immunoadsorbent assays (ELI SA), Somatic fusions were carried out using splenic lymphocytes from G Z-immune mice and the NSO/2 myeloid cell line. Primary selection of hy bridomas secreting antibodies to GZ was done using a direct ELISA, wit h GZ bound to bovine serum albumin (BSA), GZ directly bound to maleini mide preactivated plates and histamine bound to BSA, a GZ related biog enic amine present in fish meal, Four MAbs-3H4, 3H10, and 5B1 of the I gG(1) isotype, and 8G7 of the Ig(2a) isotype-were specific to GZ and d id not cross-react with histamine. Only monoclonals 3H4 and 8G7 bound GZ in solution by means of a competitive ELISA, Finally, to determine the performance of the competitive ELISA developed with the MAbs, expe riments were conducted with GZ in solution (0 to 10 mu g/ml) and with GZ labeled with horseradish peroxidase (HRP) as the tracer; the antibo dy complex was captured by using rabbit anti-mouse IgG preactivated EL ISA plates. These experiments showed that monoclonal anti-GZ-3H4 gener ates a more sensitive assay close to linearity in the range about of 0 .1 to 10 mu g/ml of GZ, No cross-reaction was observed with histamine, histidine, or lysine at all concentrations tested.