A recombinant protein-based ELISA for detecting antibodies to foot-and-mouth disease virus serotype Asia 1

J Virol Methods. 2009 Jul;159(1):112-8. doi: 10.1016/j.jviromet.2009.03.011. Epub 2009 Mar 20.

Abstract

A recombinant protein-based ELISA was evaluated for detecting antibodies to foot-and-mouth disease virus (FMDV) serotype Asia 1. The recombinant protein (rP13C) was derived from the P1 precursor and 3C protease genes that were cloned into a single expression vector and expressed in insect cells. This protein elicited a low titer of FMDV neutralizing antibodies in pigs. Its utility as a diagnostic antigen was explored in a blocking ELISA using monoclonal antibodies. The rP13C ELISA yielded higher endpoint titers than the liquid phase blocking (LPB) ELISA and virus neutralization test performed on sera from goats challenged with FMDV post-vaccination. The rP13C ELISA correctly scored the FMD international reference weak positive serum. The relative sensitivity between the rP13C ELISA and LPB ELISA was equivalent for vaccinated sera. With this comparable sensitivity, the rP13C ELISA exhibited a specificity of 99.7% for domestic naive swine, bovine and caprine sera. This report demonstrates that an ELISA using recombinant proteins has the potential to replace the LPB ELISA using an inactivated FMDV antigen as a simple and robust serological tool for screening antibodies to FMDV serotype Asia 1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3C Viral Proteases
  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Viral / isolation & purification*
  • Capsid Proteins / immunology
  • Cattle
  • Cell Line
  • Cysteine Endopeptidases / biosynthesis
  • Cysteine Endopeptidases / immunology
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Foot-and-Mouth Disease / virology*
  • Foot-and-Mouth Disease Virus / immunology
  • Foot-and-Mouth Disease Virus / isolation & purification*
  • Goats
  • Mice
  • Neutralization Tests
  • Rabbits
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / immunology
  • Sensitivity and Specificity
  • Spodoptera
  • Swine
  • Viral Proteins / biosynthesis
  • Viral Proteins / immunology

Substances

  • Antibodies, Monoclonal
  • Antibodies, Viral
  • Capsid Proteins
  • Recombinant Proteins
  • VP1 protein, Foot-and-mouth disease virus
  • Viral Proteins
  • Cysteine Endopeptidases
  • 3C Viral Proteases