• Vaccine Name: EHEC O157 subunit vaccine using his-tagged N-terminal intimin
• Target Pathogen: Escherichia coli
• Target Disease: Hemorrhagic colitis
• Vaccine Ontology ID: VO_0000505
• Type: Subunit vaccine
• Antigen: The antigen used in this vaccine was purified intimin O157, creating antibodies against EHEC O157 adhesin (Dean-Nystrom et al., 2002).
• CS1 gene engineering:
  • Type: Gene mutation
  • Description: RIHisEae is a histidine-tagged version of the entire intimin protein from EHEC O157:H7 strain 86-24 minus the N-terminal 35 amino acids, which are thought to be part of a cleaved N-terminal signal sequence. For analysis of colostrum samples, a histidine-tagged N-terminal two-thirds fragment of intimin and a histidine-tagged C-terminal one-third fragment of intimin were purified (Dean-Nystrom et al., 2002).
    
  • Detailed Gene Information: Click Here.
• Adjuvant:
  • Adjuvant name:
  • VO adjuvant ID: VO_0001260
  • Description: The adjuvant used in the vaccines was TiterMax Gold (Dean-Nystrom et al., 2002)
• Preparation: The histidine-tagged intimin O157 protein RIHisEae was purified. RIHisEae is a histidine-tagged version of the entire intimin protein from EHEC O157:H7 strain 86-24 minus the N-terminal 35 amino acids, which are thought to be part of a cleaved N-terminal signal sequence. The intimin was mixed with TiterMax Gold to form the vaccine (Dean-Nystrom et al., 2002).

Pig Response

• Host Strain: unknown crossbreed
• Vaccination Protocol: Three crossbred pregnant dams were vaccinated intramuscularly with intimin O157 mixed with TiterMax Gold adjuvant (500 μg of intimin/dose) at 2 and 4 weeks prior to farrowing (Dean-Nystrom et al., 2002).
• Immune Response: The serum anti-intimin O157 titers of the vaccinated dams after they had farrowed were >10,000, but those of the sham-vaccinated dams were ≤100 (Dean-Nystrom et al., 2002).
• Challenge Protocol: Piglets naturally farrowed suckled colostrum before inoculation with E. coli O157:H7. All piglets were inoculated with 10^6 CFU of Stx-negative E. coli O157:H7 strain 87-23 administered via stomach tube after all of the piglets had nursed and before the piglets were 8 h old (Dean-Nystrom et al., 2002).
• Efficacy: All seven of the piglets that nursed a vaccinated dam and were at least 2 h old when they were inoculated with E. coli O157:H7 had serum anti-intimin O157 titers of ≥10,000 at the time they were challenged. Two piglets in this same litter that were inoculated before they were 2 h old had a titer of 100. All eight of the piglets nursing one sham-vaccinated dam had titers of <100. Piglets that ingested colostrum containing intimin O157-specific antibodies from vaccinated dams, but not those nursing sham-vaccinated dams, were protected from EHEC O157:H7 colonization and intestinal damage. These results establish intimin O157 as a viable candidate for an EHEC O157:H7 antitransmission vaccine.