Summary
The antigenic variability of the 15 kD nucleocapsid protein of porcine reproductive and respiratory syndrome (PRRS) virus was characterized with a panel of 24 monoclonal antibodies (MAbs) raised against the American PRRS virus isolate ISU-P. Five continuous epitopes designated EpORF7-A through E were revealed by the reactivity pattern of these MAbs with 67 American field isolates, two modified-live vaccine viruses, and the European Lelystad virus as determined by the indirect immnofluorescence assay and Western immunoblotting and confirmed by additivity and blocking enzyme-linked immunosorbent assays. The reactivity pattern of isolates in the IFA permitted their subdivision into 4 American antigenic groups which represented 84.1, 11.6, 2.9 and 1.4% of viruses tested. The antigenic variation among isolates was correlated to single, group specific nucleotide substitutions and mediated by a combination of at least 4 of the 5 epitopes. EpORF7-A was conserved in all American isolates and the Lelystad virus which constituted a separate antigenic group. Consequently, monoclonal antibodies specific for EpORF7-A may prove useful as the antigenic basis for a universal diagnostic test for the PRRS virus. EpORF7-C, D and E were only present in the American isolates tested.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received April 6, 1998 Accepted September 22, 1998
Rights and permissions
About this article
Cite this article
Yang, L., Yoon, KJ., Li, Y. et al. Antigenic and genetic variations of the 15 kD nucleocapsid protein of porcine reproductive and respiratory syndrome virus isolates. Arch. Virol. 144, 525–546 (1999). https://doi.org/10.1007/s007050050523
Published:
Issue Date:
DOI: https://doi.org/10.1007/s007050050523