U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
Document Type
Article
Date of this Version
2012
Citation
Vaccine 30 (2012) 3015–3025
doi:10.1016/j.vaccine.2011.11.029
Abstract
Johne’s disease (JD), caused by Mycobacterium avium subsp. paratuberculosis (MAP), results in serious economic losses worldwide especially in cattle, sheep and goats. To control the impact of JD on the animal industry, an effective vaccine with minimal adverse effects is urgently required. In order to develop an effective vaccine, we used allelic exchange to construct three mutant MAP strains, leuD, mpt64 and secA2. The mutants were attenuated in a murine model and induced cytokine responses in J774A.1 cell. The leuD mutant was the most obviously attenuated of the three constructed mutant strains. Our preliminary vaccine trial in mice demonstrated different levels of protection were induced by these mutants based on the acid-fast bacilli burden in livers and spleens at 8 and 12 weeks post challenge. In addition, vaccination with leuD mutant induced a high level of IFN- production and significant protective efficacy in both the reduction of inflammation and clearance of acid-fast bacilli, as compared with the mock vaccinated group.
Comments
2011 Elsevier Ltd. All rights reserved.