DETECTION OF ANTIBODIES AGAINST THE ENZOO TIC BOVINE LEUKEMIA-VIRUS IN MILK AND SERUM SAMPLES BY IMMUNOBLOTTING

A method for detection of antibodies against the enzootic bovine leuke mia virus in single serum and milk samples, as well as in pooled milk samples, is described. After the electrophoretical separation of the a ntigen proteins with SDS-PAGE, a transfer onto an immobilizing membran e is done, followed by immunodetection based on the reaction of the le ukemia virus antibodies with antigen proteins. The antibody-antigen co mplex is visualized by a second, biotinylated antibody and peroxidase- avidin. This system is developed for verification of ELISA-results in surveillance of official admitted herds free of leukosis. The threshol d for positive samples is tested by the European reference serum E-4, Copenhagen, the dilution 1:25 000 is recognized as positive. The detec ted antigen-antibody reactions are determined by scanning and comparis on with the MW-markers.