The Journal of Experimental Medicine
Avanti Polar Lipids, Inc.
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text
Right arrow Full Text (PDF, 1239K)
Right arrow PPT slides of all figures
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JEM
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Abe, A.
Right arrow Articles by Brett Finlay, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Abe, A.
Right arrow Articles by Brett Finlay, B.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Facebook   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?
© The Rockefeller University Press, 0022-1007/1998/11/1907/ $5.00
The Journal of Experimental Medicine, Volume 188, Number 10, November 16, 1998 1907-1916

Articles

Two Enteropathogenic Escherichia coli Type III Secreted Proteins, EspA and EspB, Are Virulence Factors

Akio Abe*,{ddagger}, Ursula Heczko*, Richard G. Hegele§, and B. Brett Finlay*

From the * Biotechnology Laboratory, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3; the {ddagger} Department of Bacteriology, The Kitasato Institute, Minato-ku, Tokyo 108, Japan; and the § Department of Pathology and Laboratory Medicine, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada V6Z 1Y6

Enteropathogenic Escherichia coli (EPEC) belongs to a family of related bacterial pathogens, including enterohemorrhagic Escherichia coli (EHEC) O157:H7 and other human and animal diarrheagenic pathogens that form attaching and effacing (A/E) lesions on host epithelial surfaces. Bacterial secreted Esp proteins and a type III secretion system are conserved among these pathogens and trigger host cell signal transduction pathways and cytoskeletal rearrangements, and mediate intimate bacterial adherence to epithelial cell surfaces in vitro. However, their role in pathogenesis is still unclear. To investigate the role of Esp proteins in disease, mutations in espA and espB were constructed in rabbit EPEC serotype O103 and infection characteristics were compared to that of the wild-type strain using histology, scanning and transmission electron microscopy, and confocal laser scanning microscopy in a weaned rabbit infection model. The virulence of EspA and EspB mutant strains was severely attenuated. Additionally, neither mutant strain formed A/E lesions, nor did either one cause cytoskeletal actin rearrangements beneath the attached bacteria in the rabbit intestine. Collectively, this study shows for the first time that the type III secreted proteins EspA and EspB are needed to form A/E lesions in vivo and are indeed virulence factors. It also confirms the role of A/E lesions in disease processes.

Key Words: enteropathogenic Escherichia coli • attaching and effacing lesion • Esp proteins • type III secretion system • cytoskeletal rearrangement

Address correspondence to B. Brett Finlay, Biotechnology Laboratory, University of British Columbia, Rm. 237, Wesbrook Bldg., 6174 University Blvd., Vancouver, B.C., Canada V6T 1Z3. Phone: 604-822-2210; Fax: 604-822-9830; E-mail: bfinlay{at}unixg.ubc.ca

A. Abe was supported by a fellowship from The Naito Foundation. U. Heczko was supported by an Erwin-Schrödinger-Fellowship (No. Jo1417-MOB) of the Fonds zur Förderung der wissenschaftlichen Forschung. This work was supported by operating grants to B.B. Finlay from the Medical Research Council of Canada and ID Vaccine Corporation, and a Howard Hughes International Research Scholar Award, and to R.G. Hegele from the Medical Research Council of Canada/British Columbia Lung Association Scholarship Award.

A. Abe and U. Heczko contributed equally to this paper.

Abbreviations used: A/E, attaching and effacing; CLSM, confocal laser scanning microscopy; CPE, cytopathic effect; EHEC, enterohemorrhagic Escherichia coli; EPEC, enteropathogenic Escherichia coli; LB, Luria-Bertani; LEE, locus of enterocyte effacement; REPEC, rabbit EPEC; SEM, scanning electron microscopy; STX, Shiga toxin; TEM, transmission electron microscopy; Tir, translocated intimin receptor; TxR, Texas red.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?




  Home | Help | Feedback | Subscriptions | Archive | Search
TABLE OF CONTENTS