Attenuated Actinobacillus pleuropneumoniae double-deletion mutant S-8?clpP/apxIIC confers protection against homologous or heterologous strain challenge.

ABSTRACT: Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, which leads to large economic losses to the swine industry worldwide. In this study, S-8?clpP?apxIIC, a double-deletion mutant of A. pleuropneumoniae was constructed, and its safety and protective efficacy were evaluated in pigs.The S-8?clpP?apxIIC mutant exhibited attenuated virulence in a murine (BALB/c) model, and caused no detrimental effects on pigs even at a dose of up to 1.0?×?109 CFU. Furthermore, the S-8?clpP?apxIIC mutant was able to induce a strong immune response in pigs, which included high levels of IgG1 and IgG2, stimulated gamma interferon (IFN-?), interleukin 12 (IL-12), and interleukin 4 (IL-4) production, and conferred effective protection against the lethal challenge with A. pleuropneumoniae serovars 7 or 5a. The pigs in the S-8?clpP?apxIIC immunized groups have no lesions and reduced bacterial loads in the lung tissue after challenge.The data obtained in this study suggest that the S-8?clpP?apxIIC mutant can serve as a highly immunogenic and potential live attenuated vaccine candidate against A. pleuropneumoniae infection.

SUBMITTER: Xie F 

PROVIDER: S-EPMC5219649 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature