COMPARISON OF 4 TESTS TO EVALUATE THE REACTIVITY OF RABBIT SERA AGAINST ENVELOPE OR GAG-RELATED PROTEINS OF BOVINE LEUKEMIA-VIRUS (BLV)

Bovine leukemia virus (BLV) has a long latency period during which ani mals are inapparently infected, may spread the disease, and are only d etected by serological techniques or by the most cumbersome molecular biology techniques. We have compared techniques for detecting either t otal antibodies (ELISA), anti-p24 and Gag-related proteins (Western bl ot), or anti-gp51 (agar gel immunodiffusion, AGID, and syncytia inhibi tion, SI) in rabbits inoculated experimentally with inocula of variabl e immunogenicity. The two tests to detect antibodies to gp51 correlate d well in sera clearly positive or clearly negative by either one, but cell-elation was poor in the intermediate groups. All sera positive b y AGID were also positive by ELISA, but results did not agree in sera negative by AGID, ELISA proving to be more sensitive. Western blot was a good technique for detecting antibodies against Gag-related protein s. However, no band was identified to clearly correspond to anti-Env-r elated proteins. As for other retroviruses, testing of animals for inf ection with BLV should include the detection of antibodies anti-Gag an d anti-Env proteins. (C) 1998 Elsevier Science B.V.