Diagnostic application of immunoperoxidase monolayer assay using monoclonal antibodies produced against equine arteritis virus 14-kDa nucleocapsid protein.

Two monoclonal antibodies against the Bucyrus strain of equine arteritis virus (EAV) were produced, and according to immunoperoxidase reaction following Western blot of electrophoresed EAV structural proteins, they recognized the nucleocapsid (N) protein antigen (14-kDa protein). Besides reacting with the blotted polypeptide, the antibodies of the two clones (designated 1H1 and 4G6) selected from 576 have shown high affinity and specificity to intracellular virus antigen as well. Both antibodies reacted with the representatives of the different subtypes of equine arteritis virus providing a suitable general tool for diagnostic purposes using immunoperoxidase monolayer assay (IPMA). Isotypes of the antibodies were examined by Ouchterlony immundiffusion assay. The subtyping of the two examined MAbs proved that the light chains are of the kappaisotype, whereas the heavy chains were identified as IgG 1 isotype.