PRODUCTION OF MONOCLONAL-ANTIBODIES WITH DISTINCT NEUTRALIZING ACTIVITY AGAINST VIRULENT AND THE ATTENUATED BARTHA STRAIN OF AUJESZKYS-DISEASE VIRUS

Three monoclonal antibodies (MoAbs) with in vitro neutralizing activit y against virulent Aujeszky's disease virus (ADV) were produced. MoAbs 2E9 and 1H1 neutralized the virus only in the presence of exogenous c omplement, whereas MoAb G4 neutralized the virus in the absence of com plement. However, none of the MoAbs were able to neutralize the natura lly attenuated Bartha strain of ADV even in the presence of complement . Western blot analysis against virulent VDA proteins, resolved by SDS -PAGE under non-reducing conditions, showed that these MoAbs react aga inst a 138K protein, and against a 68K protein under reducing conditio ns. A very faint reaction was noticed also against a 116K protein unde r reducing conditions. These results indicate a reaction against a dis ulfide linked protein, analogous to protein gII of ADV. This distinct neutralizing activity to a disulfide linked complex protein suggests d ifferences in neutralizing epitopes of this protein from virulent and attenuated virus. These monoclonal antibodies may be good candidates f or the use as makers for comparative analysis of virulent and attenuat ed strains of ADV.