Fig. 6
Protective immunity induced by the RHΔku80ΔompdcΔuprt vaccine against T. gondii challenge infection in mice. a–c Survival curves of naïve or RHΔku80ΔompdcΔuprt immunized mice infected with RHΔku80, ME49 and WH6. Two weeks after the last immunization, mice were intraperitoneally (i.p.) challenged with 1 × 103 T. gondii tachyzoites of RHΔku80, ME49 and WH6 strains (5 mice/strain), and monitored for 30 days. d Organ damage in vaccinated mice and naïve mice after challenge with the RHΔku80 and ME49 strains. e Two weeks after the last immunization, whole splenocytes, CD4+, CD8+ and CD19+ splenocytes were harvested, and 1 × 107 total immune splenocytes, 2 × 106 CD8+ T cells, 2 × 106 CD4+ T cells, 2 × 106 CD19+ B cells, or 1 × 107 total naïve splenocytes were transferred to naïve recipient mice. Twenty-four hours after transfer mice mice were challenged with 1 × 103 T. gondii RHΔku80 i.p. and monitored for survival. f From day 0 to day 4 after infection, mice were treated with sera from RHΔku80ΔompdcΔuprt-vaccinated and naïve mice. g Parasite load detection after one day of sera treatment. *P < 0.05, **P < 0.01, *** P < 0.001 by log-rank (Mantel–Cox) test, ns not significant