A highly specific and sensitive competitive enzyme-linked immunosorbent assay (ELISA) based on baculovirus expressed pseudorabies virus glycoprotein gE and gI complex

A direct competition enzyme-linked immunosorbent assay (ELISA) based on bac ulovirus expressed complex of pseudorabies virus (PRV) glycoproteins E (gE) and I (gI) has been developed. For that purpose gE and gI genes of PRV wer e co-expressed in insect cells, Complex formation was confirmed by radioimm unoprecipitation assay. The specificity and sensitivity of the test were ev aluated and compared with an ELISA using only,gE as an antigen and a commer cially available test, For validation, 245 negative sera and 165 positive s era have been tested. The gE/gI ELISA had a higher sensitivity and specific ity when compared with the ELISA using only gE as the antigen. Both sensiti vity and specificity were comparable with the commercially available test. Moreover, the rest based on the baculovirus gE/gI complex allows the detect ion of anti-gE antibodies in pig serum as early as two weeks after infectio n. The gE/gI ELISA test is easy to perform; its additional advantage is tha t the gE/gI antigen can be produced in baculovirus system in large quantiti es without handling live pseudorabies virus, (C) 1999 Elsevier Science B.V. All rights reserved.