title: Oral administration of live Shigella vaccine candidates in rhesus monkeys show no evidence of competition for colonization and immunogenicity between different serotypes.
abstract: Live oral monovalent Shigella flexneri 2a vaccine candidates as well as bivalent formulations with Shigella sonnei were evaluated in a rhesus monkey model for colonization and immunogenicity. Freshly harvested suspensions of S. flexneri 2a vaccine candidates WRSf2G12 and WRSf2G15 as well as S. sonnei vaccine candidate WRSs3 were nasogastrically administered to groups of rhesus monkeys, Macaca mulatta, either in a monovalent form or when combined with each other. The animals were monitored daily for physical well-being, stools were subjected to quantitative colony immunoblot assays for bacterial excretion and blood and stools were evaluated for humoral and mucosal immune responses. No clinical symptoms were noted in any group of animals and the vaccine candidates were excreted robustly for 48-72h without significant changes in either the magnitude or duration of excretion when given as a monovalent or as bivalent mixtures. Similarly, immunological interferences were not apparent in the magnitude of humoral and mucosal immune responses observed toward Shigella-specific antigens when monkeys were fed monovalent or bivalent formulations. These results predict that a multivalent live oral vaccine of more than one serotype can have a favorable outcome for protection against shigellosis.
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: R T
authors: RT
authors: Ranallo
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: R
authors: R
authors: Kaminski
authors: Enteric Diseases Branch, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: S
authors: S
authors: Baqar
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: M
authors: M
authors: Dutta
authors: Department of Veterinary Medicine, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States.
authors: L A
authors: LA
authors: Lugo-Roman
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: T
authors: T
authors: Boren
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States.
authors: S
authors: S
authors: Barnoy
authors: Bacterial Diseases Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, United States. Electronic address: Malabi.venkatesan@us.army.mil.
authors: M M
authors: MM
authors: Venkatesan
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D057138:Bacterial Shedding; D005243:Feces / Q000382:microbiology; D056724:Immunity, Humoral; D018928:Immunity, Mucosal; D008253:Macaca mulatta; D008297:Male; D012703:Serotyping; D022281:Shigella Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012763:Shigella flexneri / Q000145:classification / Q000276:immunology*; D012764:Shigella sonnei / Q000145:classification / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D022281:Shigella Vaccines
keywords: Colonization; Immunogenicity; Live bivalent vaccine candidates; Rhesus monkeys; Shigella