Protection Induced by Oral Vaccination with a Recombinant <i>Yersinia pseudotuberculosis</i> Delivering <i>Yersinia pestis</i> LcrV and F1 Antigens in Mice and Rats against Pneumonic Plague
Saugata Majumder, Rachel M. Olson, Amit Singh, Xiuran Wang, Peng Li, Hatem Kittana, Paul E. Anderson, Deborah M. Anderson, Wei Sun
Abstract
plasmid (pYA5199) (designated Yptb1[pYA5199]) simultaneously delivers Y. pestis LcrV and F1. The attenuated Yptb1(pYA5199) localized in the Peyer's patches, lung, spleen, and liver for a few weeks after oral immunization without causing any disease symptoms in immunized rodents. An oral prime-boost Yptb1(pYA5199) immunization stimulated potent antibody responses to LcrV, F1, and Y. pestis whole-cell lysate (YPL) in Swiss Webster mice and Brown Norway rats. The prime-boost Yptb1(pYA5199) immunization induced higher antigen-specific humoral and cellular immune responses in mice than a single immunization did, and it provided complete short-term and long-term protection against a high dose of intranasal Y. pestis challenge in mice. Moreover, the prime-boost immunization afforded substantial protection for Brown Norway rats against an aerosolized Y. pestis challenge. Our study highlights that Yptb1(pYA5199) has high potential as an oral vaccine candidate against pneumonic plague.