The EtpA exoprotein of enterotoxigenic Escherichia coli promotes intestinal colonization and is a protective antigen in an experimental model of murine infection. Infect Immun 2008 May;76(5):2106-12
Date
02/21/2008Pubmed ID
18285493Pubmed Central ID
PMC2346670DOI
10.1128/IAI.01304-07Scopus ID
2-s2.0-42949162632 (requires institutional sign-in at Scopus site) 59 CitationsAbstract
The enterotoxigenic Escherichia coli (ETEC) strains are major causes of morbidity and mortality due to diarrheal illness in developing countries. At present, there is no broadly protective vaccine for this diverse group of pathogens. The EtpA protein, identified in ETEC H10407 in a recent search for candidate immunogens, is a large glycosylated exoprotein secreted via two-partner secretion (TPS). Similar to structurally related molecules, EtpA functions in vitro as an adhesin. The studies reported here use a recently developed murine model of ETEC intestinal colonization to examine the immunogenicity and protective efficacy of EtpA. We report that mice repeatedly exposed to ETEC are protected from subsequent colonization and that they mount immune responses to both EtpA and its presumed two-partner secretion transporter (EtpB) during the course of experimental infection. Furthermore, isogenic etpA deletion mutants were impaired in the colonization of mice, and intranasal immunization of mice with recombinant EtpA conferred protection against ETEC H10407 in this model. Together, these data suggest that EtpA is required for optimal colonization of the intestine, findings paralleling those of previous in vitro studies demonstrating its role in adherence. EtpA and other TPS proteins may be viable targets for ETEC vaccine development.
Author List
Roy K, Hamilton D, Allen KP, Randolph MP, Fleckenstein JMAuthor
Kenneth Paul Allen DVM Associate Professor in the Research Office department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adhesins, BacterialAnimals
Antibodies, Bacterial
Colony Count, Microbial
Enterotoxigenic Escherichia coli
Escherichia coli Infections
Escherichia coli Proteins
Escherichia coli Vaccines
Feces
Gene Deletion
Intestine, Small
Membrane Glycoproteins
Mice
Virulence
Virulence Factors