A comparison of immunogenicity and in vivo distribution of Salmonella enterica serovar Typhi and Typhimurium live vector vaccines delivered by mucosal routes in the murine model

We evaluated the immune responses elicited by attenuated Salmonella enteric a serovar Typhi vaccine strain CVD 909-htrA and serovar Typhimurium strain SL3261 alone or as live vectors carrying a plasmid encoding fragment C of t etanus toxin (pTETnir15) in mice immunized intranasally and orogastrically, as well as the in vivo distribution of vaccine organisms following immuniz ation. Higher serologic and proliferative responses against both vector and the foreign antigen were elicited when vaccines were delivered by intranas al route. Whereas both Salmonella strains were detected in the nasal tissue , lungs, and Peyer's patches following intranasal and orogastric immunizati on, larger numbers of vaccine organisms were recovered from these tissues w hen the vaccines were delivered intranasally. (C) 2000 Elsevier Science Ltd . Ail rights reserved.