• Vaccine Name: Typhi strain Ty21a-LPS-Shigella
• Target Pathogen: Shigella
• Target Disease: Shigellosis
• Vaccine Ontology ID: VO_0004701
• Type: Recombinant vector vaccine
• Status: Research
• Host Species for Licensed Use: Baboon
• Vector:
  • Vector name:
  • VO vector ID: VO_0001075
  • Description: (Dharmasena et al., 2013)
• Preparation: Ty21a-Ss simultaneously expresses both homologous Ty21a and heterologous S. sonnei O-antigens (Dharmasena et al., 2013).
• Immunization Route: Intramuscular injection (i.m.)

Mouse Response

• Vaccination Protocol: Mice were immunized with vaccine candidate strains (Ty21a-Ss) or negative controls Ty21a alone and PBS (Dharmasena et al., 2013).
• Vaccine Immune Response Type: VO_0003057
• Challenge Protocol: Immunized and control mice were challenged intraperitoneally, 2 weeks after final immunization, with ∼5 × 10^6 CFU/ml of freshly grown, mid-log-phase virulent S. sonnei strain 53GI in 0.25 ml (∼2 × 10^6 CFU per mouse) of 5% hog gastric mucin (Sigma) dissolved in sterile saline (i.e. approximately 100 times the 50% lethal infectious dose [LD50]) (Dharmasena et al., 2013).
• Efficacy: Ty21a-Ss elicited strong dual anti-LPS serum immune responses and 100% protection in mice against a virulent S. sonnei challenge (Dharmasena et al., 2013).