Towards a Vaccine for Enterotoxigenic E.coli (ETEC): Comparison of Protection Following Intragastric (IG) or Intranasal (IN) Immunization with an Attenuated O157:H7 E.coli Strain (ZCR533) Expressing ETEC Antigens .

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Event Abstract Back to Event Towards a Vaccine for Enterotoxigenic E.coli (ETEC): Comparison of Protection Following Intragastric (IG) or Intranasal (IN) Immunization with an Attenuated O157:H7 E.coli Strain (ZCR533) Expressing ETEC Antigens . Edgar Boedeker1* 1 University of New Mexico, Division of Gastroenterology, United States Byrd W 1 , Boedeker E 1* 1Division of Gastroenterology, University of New Mexico, Albuquerque, NM, USA eboedeker@salud.unm.edu We have previously shown that truncation of intimin in a rabbit enteropathogenic E.coli (REPEC) strain yields an attenuated strain which is immunogenic and protective against homologous REPEC challenge1. We have developed a similar intimin mutant (designated ZCR533) in an O157:H7 shiga toxin producing E.coli (STEC) strain to serve not only as an STEC vaccine, but also for use as a vector to express antigens of other pathogens. To develop a safe, live attenuated vaccine against enterotoxigenic E.coli (ETEC) we expressed two critical ETEC antigens, CFA/I and detoxified LT, in ZCR533 and then tested the resulting strains for immunogenicity and protective efficacy in a streptomycin-treated treated mouse model of intestinal ETEC infection. BALB/c mice were vaccinated by the IG or IN routes, then challenged with ETEC H10407 or purified LT. IG delivery of three doses, or IN delivery of two doses, of the vaccine strain to BALB/C mice induced serum IgG and mucosal IgA antibodies to CFA/I and LT. Both IG and IN administration of the ETEC vaccine significantly reduced intestinal bacterial colonization after an oral challenge with ETEC (vac. vs. sham, P<0.05). However, decreased intestinal fluid accumulation following oral challenge with ETEC, or with purified LT, was seen only in the IG vaccinated mice (vac. vs. sham, P<0.05), but not in those vaccinated IN. These studies suggest that both IG and IN administered vaccine led to protective serum and mucosal responses against colonization, but IG vaccination may better protect against toxin-induced fluid accumulation. Reference: 1. Agin et al. Infect. Immun. 73:6608-19, 2005 Keywords: attenuated vaccine against ETEC, intimin mutant Conference: ECMIS - E. coli and the Mucosal Immune System : Interaction, Modulation and Vaccination, Ghent, Belgium, 2 Jul - 5 Jul, 2011. Presentation Type: Oral Presentation Topic: Abstracts Citation: Boedeker E (2012). Towards a Vaccine for Enterotoxigenic E.coli (ETEC): Comparison of Protection Following Intragastric (IG) or Intranasal (IN) Immunization with an Attenuated O157:H7 E.coli Strain (ZCR533) Expressing ETEC Antigens .. Front. Immunol. Conference Abstract: ECMIS - E. coli and the Mucosal Immune System : Interaction, Modulation and Vaccination. doi: 10.3389/conf.fimmu.2012.01.00006 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 13 Oct 2011; Published Online: 09 Jan 2012. * Correspondence: Prof. Edgar Boedeker, University of New Mexico, Division of Gastroenterology, Albuquerque, New Mexico, 87031, United States, eboedeker@salud.unm.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Edgar Boedeker Google Edgar Boedeker Google Scholar Edgar Boedeker PubMed Edgar Boedeker Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.