FIG 6.

Targeting TgCoq1 with a lipophilic bisphosphonate. (A) Structure of BPH-1218. (B) Percent inhibition by the drug BPH-1218 of the parental and the TgCoq1 overexpressing mutant (Coq1-OE) showing that the Coq1-OE is more resistant to BPH-1218 (average from 3 independent experiments). (C) Western blot analysis showing the increase in expression of the HA tagged TgCoq1 in the overexpressing cell line. (D) Quantification of plaque sizes for growth of the wild-type cell line grown with BPH-1218 for 7 days (7⁺) and then without drug (7⁻) for 7 days or continuously grown in BPH-1218 for 14 days (14⁺) (BPH-1218 at indicated concentrations). We also tested no BPH-1218 and the parasites completely lysed the monolayer and were not quantifiable (data summarized from 3 biological replicates, Two-way ANOVA statistical analysis). (E) BPH-1218 protects against a lethal in vivo infection in mice. The indicated doses (mg/kg/day) of BPH-1218 were inoculated for 10 days after mice were infected with a lethal dose of RH parasites. ED₅₀ = 0.69 mg/kg/day (data summarized from 3 independent experiments). (F) Challenge with 100 RH parasites of living mice on day 30 after treatment for 10 days with 1 mg/kg/day BPH-1218. (G) Infection of mice with a luciferase-expressing strain of RH parasites shows BPH treatment of mice clears the infection. More details are given in Materials and Methods. (H) Quantification of luciferase expression from 2 experiments, each with 6 mice (3 controls and 3 treated).