%0 Journal Article %A Matsui, Hidenori %A Fukiya, Satoru %A Kodama-Akaboshi, Chie %A Eguchi, Masahiro %A Yamamoto, Tomoko %T Mouse models for assessing the cross-protective efficacy of oral non-typhoidal Salmonella vaccine candidates harbouring in-frame deletions of the ATP-dependent protease lon and other genes %D 2015 %J Journal of Medical Microbiology, %V 64 %N 3 %P 295-302 %@ 1473-5644 %R https://doi.org/10.1099/jmm.0.000014 %I Microbiology Society, %X In BALB/c mouse models of Salmonella enterica serovar Typhimurium infection, a single oral immunization with a mutant strain with an insertion of the chloramphenicol resistance gene into the ATP-dependent protease clpP or lon gene decreased the number of salmonellae in each tissue sample 5 days after oral challenge with virulent S. Typhimurium at weeks 26 and 54 post-immunization. These data suggested that an oral immunization with the ClpP- or Lon-disrupted S. Typhimurium strain could provide long-term protection against oral challenge with virulent S. Typhimurium. Accordingly, recombinant oral non-typhoidal Salmonella (NTS) vaccines were constructed by incorporating mutants of both S. Typhimurium and S. enterica serovar Enteritidis harbouring stable in-frame markerless deletions of the clpP–lon–sulA (suppressor of lon), lon–sulA or lon–msbB (acyltransferase) genes. Amongst these orally administered vaccine candidates, those with the lon–sulA gene deletion mutants of S. Typhimurium and S. Enteritidis protected BALB/c and C57BL/6J mice against oral challenge with both virulent S. Typhimurium and virulent S. Enteritidis. Therefore, the in-frame markerless lon–sulA gene deletion mutant of S. Typhimurium or S. Enteritidis could be a promising cross-protective NTS live vaccine candidate for practical use in humans. %U https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.000014