Sensitive and specific detection of enteropathogenic and enterohemorrhagic Escherichia coli using recombinant anti-intimin antibody by immunofluorescence assay

Diagn Microbiol Infect Dis. 2013 Dec;77(4):301-3. doi: 10.1016/j.diagmicrobio.2013.08.021. Epub 2013 Oct 2.

Abstract

The main and common virulence factor expressed by enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) is intimin, a 94-kDa outer membrane protein, which is a product of the eae gene, and, thus, an excellent target for the detection of these pathogens. Among the methods for detection of virulence factor expression, immunoassays can be considered the first alternative to either animal use or in vitro culture cells assays, for which polyclonal and/or monoclonal antibodies are raised. In the present work, we evaluated the sensitivity and specificity of an intimin recombinant antibody (scFv-intimin) using immunofluorescence assay. The scFv-intimin detected typical EPEC, atypical EPEC, and EHEC isolates (100% sensitivity) with no detection of eae- isolates (100% specificity). Thus, immunofluorescence is an effective and rapid method, and scFv-intimin, an excellent tool for the diagnosis of diarrhea caused by EPEC and EHEC and also can be employed in case-control epidemiological surveys.

Keywords: Detection; EHEC; EPEC; Intimin; Recombinant antibody.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Bacterial / immunology*
  • Enterohemorrhagic Escherichia coli / classification*
  • Enteropathogenic Escherichia coli / classification*
  • Escherichia coli Proteins / immunology*
  • Fluorescent Antibody Technique, Indirect / methods*
  • Humans
  • Sensitivity and Specificity
  • Single-Chain Antibodies / chemistry
  • Single-Chain Antibodies / genetics
  • Single-Chain Antibodies / immunology*
  • Virulence Factors / immunology*

Substances

  • Adhesins, Bacterial
  • Escherichia coli Proteins
  • Single-Chain Antibodies
  • Virulence Factors
  • eaeA protein, E coli