Find in Library

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.