False-positive results in a recombinant severe acute respiratory syndrome-associated coronavirus (SARS-CoV) nucleocapsid enzyme-linked immunosorbent assay due to HCoV-OC43 and HCoV-229E rectified by Western blotting with recombinant SARS-CoV spike polypeptide

J Clin Microbiol. 2004 Dec;42(12):5885-8. doi: 10.1128/JCM.42.12.5885-5888.2004.


Using paired serum samples obtained from patients with illness associated with increases in anti-human coronavirus OC43 (HCoV-OC43) or anti-HCoV-229E antibodies, we examined the possibility of false-positive results detected in a recombinant severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) nucleocapsid protein immunoglobulin G enzyme-linked immunosorbent assay (ELISA). Three of the 21 and 1 of the 7 convalescent-phase serum samples from persons with increases in antibodies against HCoV-OC43 and HCoV-229E, respectively, tested positive by the recombinant SARS-CoV nucleocapsid protein-based ELISA. None of these samples were found to contain a specific antibody in the recombinant SARS-CoV spike polypeptide-based Western blot assay.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antibodies, Viral / blood
  • Blotting, Western
  • Coronavirus Nucleocapsid Proteins
  • Cross Reactions
  • Enzyme-Linked Immunosorbent Assay
  • False Positive Reactions
  • Humans
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / immunology*
  • Nucleocapsid Proteins / genetics
  • Nucleocapsid Proteins / immunology*
  • Peptides / genetics
  • Peptides / immunology
  • Recombinant Proteins / immunology*
  • SARS Virus / immunology*
  • Severe Acute Respiratory Syndrome / diagnosis*
  • Severe Acute Respiratory Syndrome / virology
  • Spike Glycoprotein, Coronavirus
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / immunology*


  • Antibodies, Viral
  • Coronavirus Nucleocapsid Proteins
  • Membrane Glycoproteins
  • Nucleocapsid Proteins
  • Peptides
  • Recombinant Proteins
  • Spike Glycoprotein, Coronavirus
  • Viral Envelope Proteins