Protection from enteric and respiratory Infections by intranasal delivery of antigens along with <em>E. coli</em> heat labile enterotoxin as an adjuvant — ASN Events
  1. Schedule
  2. Session 7A New Adjuvant Technology I (Concurrent streams)
  3. Protection from enteric and respiratory Infections by intranasal delivery of antigens along with E. coli heat labile enterotoxin as an adjuvant

Protection from enteric and respiratory Infections by intranasal delivery of antigens along with E. coli heat labile enterotoxin as an adjuvant (#33)

David H. Francis 1 2 , Feng Li 1 2 , Jun Lin 1 , Mojun Zhao 1 2 , Kristina S. Mateo 1 , Vicror C. Huber 3
  1. South Dakota State University, Brookings, South, United States
  2. Brookings Biomedical, Inc., Brookings, South Dakota, United States
  3. Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota, United States

We tested the efficacy in young piglets of intranasal-delivered vaccines for enteric (enterotoxigenic E. coli; ETEC) and respiratory (influenza type A) infections utilizing E. coli heat-labile enterotoxin (LT) as a mucosal adjuvant. The ETEC vaccine consisted of purified K88 (F4) antigen and LT. Inactivated swine influenza H1N1 virus was added to make the ETEC vaccine a bivalent product. Significant mucosal and systemic immune responses to the immunogens were observed. Upon challenge with K88+/LT+/STb+ ETEC, none of 20 vaccinates, but 15/19 controls became moribund or died. Vaccinates gained weight while controls lost significant weight due to dehydration. Vaccination with K88 alone afforded partial protection, while LT alone did not. Addition of influenza virus to the vaccine did not alter the efficacy of vaccine for ETEC, but provided protection against the homologous influenza H1N1 strain. Virus was isolated by nasal culture from 7/7 controls challenged with the homologous (H1N1) virus strain, and 8/8 LT-only vaccinates, but 0/12 vaccinates. Vaccinates challenged with a heterologous strain (H3N2) also shed virus. Homologous virus RNA was found in lungs of most controls, but none of the vaccinates. These studies show the efficacy of mucosal delivery with LT adjuvant in protecting piglets from diseases involving mucosal epithelium.