Evaluation of Polyclonal Antibodies Against Recombinant FlaB Protein for Detection

Objective _ _ To produce and evaluate polyclonal antibodies against recombinant FlaB (rFlaB), a conserved 35 kDa flagellin protein of Leptospira spp. Materials and Methods _ _ L. interrogans serovar Canicola strain Hond Utrecht IV was chosen as a target for cloning. A fusion protein of histidine and FlaB (His-FlaB) was expressed as an antigen for producing polyclonal antibodies in a rabbit. The specificity of polyclonal antibodies was confirmed by immunoblotting and indirect immunofluorescent antibody technique. Purified rFlaB and whole-cell antigen prepared from both pathogenic and non-pathogenic leptospires as well as other bacteria were used as antigens. Results _ _ In application of the polyclonal antibodies to detect Leptospira spp., antisera against recombinant FlaB protein are highly specific as indicated by the recognition of major bands at 35 kDa region of leptospiral antigens by immunoblotting. Therefore, the polyclonal antibodies can be used to detect leptospira serovars with high efficiency for discrimination between leptospires and other bacteria by indirect immunofluorescent assay. Conclusion _ _ This study indicated that the polyclonal antibodies had a potential to use for detecting Leptospira spp