Kafkas Üniversitesi Veteriner Fakültesi Dergisi 2020 , Vol 26 , Issue 3
A Mutant of Listeria monocytogenes Shows Decreased Virulence and Confers Protection Against Listeriosis in Mice
Jingjing REN1, Mingwei YANG1, Pengyan WANG1, Jianjun JIANG1, Genqiang YAN
1College of Animal Science and Technology, Shihezi University, Shihezi, Xinjiang, 832003, P. R. CHINA DOI : 10.9775/kvfd.2019.23466 This research was performed to obtain a safe and highly immunogenic Listeria strain and evaluate the biological characteristics of the deletion mutant. Based on homologous recombination technology, we constructed a deletion mutant Lm90-ΔinlB of L. monocytogenes. Meanwhile, we characterized its safety and protective efficacy against listeriosis infection in mice. The results showed that the virulence of Lm90-ΔinlB could significantly decrease compared with the parental strain (Lm90). The deletion strain retained hemolytic activity and induced CD8+ T cell response comparable to that of Lm90. Mice immunized with Lm90-ΔinlB were capable of stimulating specific CD8+ T cells to the listerial epitopes LLO91-99 and P60217-225 at levels equivalent to Lm90. Importantly, immunization of mice with Lm90-ΔinlB displayed good protection against listeriosis. In conclusion, strain Lm90-ΔinlB is a vaccine candidate with the potential to be more immunogenic yet considerably less toxic than the parental strain. Keywords : Listeria monocytogenes, inlB gene, CD8+ T cells, Pprotective efficacy, Vaccine