Skip to main content
. 2019 Jul 10;26(1):135–146.e5. doi: 10.1016/j.chom.2019.05.006

Figure 6.

Figure 6

Infection Results in Protective Immunity That Can Be Induced with an Attenuated Vaccine

(A) Schematic outline of challenge experiments for B, C, and D.

(B) C57BL/6 mice were subjected to primary infection as indicated, followed by a challenge with 100,000 oocysts of transgenic C. tyzzeri. n = 9 total mice, 3 per group.

(C) Summary of parasite burden (total flux over the two-week imaging period) comparing naive and previously infected mice. n = 36 total mice, 18 per group, over 5 independent experiments. Data represent mean ± SD with significance determined using a Students t test (∗∗∗∗p < 0.00005).

(D) Parasite burden of challenge with and without intervening paromomycin treatment. n = 9 total mice, 3 per group, and data represent mean ± SD with significance determined using one-way ANOVA with Dunnett multiple comparison test (∗∗p < 0.005). Individual parasite burden by imaging and fecal parasite shedding by qPCR in Figure S4.

(E) Schematic outline of vaccination experiments for F–I.

(F) Mice were infected or vaccinated as indicated and then challenged with 100,000 transgenic C. tyzzeri oocysts. Total parasite burden from whole animal imaging is shown. Individual parasite burden by imaging and fecal parasite shedding by qPCR in Figure S5. Note that live infection and vaccination results in comparable protection. n = 30 mice, with each dot representing the total parasite burden for a single mouse. Data are mean ± SD and significance is determined using one-way ANOVA with Dunnett multiple comparisons test (∗∗p < 0.005, ∗∗∗p < 0.0005, and ∗∗∗∗p < 0.00005).

(G–I) Mice were vaccinated with oocysts attenuated by 300 gray of gamma irradiation then challenged with 1000,000 transgenic C. tyzzeri oocysts. Total parasite burden from whole animal imaging is shown. Note the large difference in parasite tissue burden of mice deficient IFNγ (I) compared to both WT C57BL/6 mice (G) and mice that lack mature B and T cells (H). n = 10 mice for each strain, with each dot representing the total parasite burden for a single mouse. Data are mean ± SD and significance is determined using Student’s t test comparing naive and vaccinated mice within each strain (∗∗∗p < 0.0005).