This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Girard, F. Articles by Fairbrother, J. M. Search for Related Content PubMed PubMed Citation Articles by Girard, F. Articles by Fairbrother, J. M.

 Previous Article  |  Next Article 

Infection and Immunity, September 2005, p. 5514-5523, Vol. 73, No. 9
0019-9567/05/$08.00+0     doi:10.1128/IAI.73.9.5514-5523.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Host Immune Status Influences the Development of Attaching and Effacing Lesions in Weaned Pigs

Groupe de recherche sur les maladies infectieuses du porc (GREMIP),¹ Département de pathologie et microbiologie, Faculté de médecine vétérinaire, Université de Montréal, Québec, Canada,³ Laboratoire de Pharmacologie-Toxicologie, INRA, Toulouse, France,² Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada⁴

Received 7 December 2004/ Returned for modification 4 April 2005/ Accepted 5 May 2005

Attaching and effacing Escherichia coli (AEEC) has been associated with naturally occurring attaching and effacing (A/E) lesions in weaned pigs, and although A/E lesions have been experimentally reproduced in newborn piglets, such lesions have been much more difficult to induce in older conventional pigs. Hence, the aim of this study was to examine the effect of oral administration of dexamethasone on the development of A/E lesions in weaned pigs challenged with a porcine enteropathogenic E. coli (PEPEC) strain and to investigate the involvement of local intestinal cytokine response. Dexamethasone, given orally at a dosage of 3 mg kg of body weight^–1, significantly enhanced both the colonization of the challenge strain and the prevalence of foci of intimately adherent bacteria, resulting in extensive A/E lesions in the ileum, cecum, and colon of challenged pigs. We also confirmed the expression of both intimin and Tir by PEPEC strain ECL1001 in A/E lesions in vivo, which is, to our knowledge, the first report of the involvement of the latter proteins in any AEEC infections in vivo. Moreover, semiquantitative reverse transcription-PCR demonstrated that interleukin 1ß (IL-1ß), IL-6, IL-8, and, to a lesser extent, IL-12p40 are significantly upregulated in the ileum following challenge with strain ECL1001, whereas dexamethasone blocks such upregulation. Taken together, our results strongly suggested that host immune status influences the development of A/E lesions in weaned pigs, and it appears that IL-1ß, IL-6, IL-8, and, to a lesser extent, IL-12p40 are expressed during infection of weaned pigs by PEPEC and may contribute to the natural resistance of the host against PEPEC infection.

Editor: A. D. O'Brien

This article has been cited by other articles:

• Brundige, D. R., Maga, E. A., Klasing, K. C., Murray, J. D. (2008). Lysozyme Transgenic Goats' Milk Influences Gastrointestinal Morphology in Young Pigs. J. Nutr. 138: 921-926 [Abstract] [Full Text]  
• Girard, F., Dziva, F., van Diemen, P., Phillips, A. D., Stevens, M. P., Frankel, G. (2007). Adherence of Enterohemorrhagic Escherichia coli O157, O26, and O111 Strains to Bovine Intestinal Explants Ex Vivo. Appl. Environ. Microbiol. 73: 3084-3090 [Abstract] [Full Text]